Superfund record of decision (EPA Region 4): Alabama Army Ammunition Plant, Area B soils operable unit, Childersburg, AL, November 14, 1995

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

1996-03-01

This decision document presents the selected remedial action for the contaminated soils and sediments in Study Areas, 6, 7, and 21, and the Industrial Sewer System (ISS) in Study Areas 6, 7, and 10 within Area B at the Alabama Army Ammunition Plant (ALAAP), Childersburg, Alabama. The Area B Soils Operable Unit addresses the principal threats from soils and sediments in Study Areas 6, 7, and 21, and underground industrial sewer lines in Study Areas 6, 7, and 10. The soils and sediments and the industrial sewer lines are contaminated with explosives and lead.

Identification of in-sewer sources of organic solids contributing to combined sewer overflows.

PubMed

Ahyerre, M; Chebbo, G

2002-09-01

Previous research has shown that combined sewer systems are the main source of particle and organic pollution during rainfall events contributing to combined sewer overflow. The aim of this article is to identify in an urban catchment area called "Le Marais", in the center of Paris, the types of sediments that are eroded and contribute to the pollution of combined sewer overflow. Three sediment types are considered: granular material found in the inverts of pipes, organic biofilms and organic sediment at the water bed interface, identified as an immobile layer in the "Le Marais" catchment area. The method used consist, firstly, of sampling and assessing the organic pollutant loads and metallic loads of the particles in each type of sediment. Then, the mass of each type of sediment is assessed. The mass and the characteristics of each type of sediment is finally compared to the mass and characteristics of the particles eroded in the catchment area, estimated by mass balances, in order to find the source of eroded particles. The only identified type of deposit that can contribute to combined sewer overflows is the organic layer. Indeed, the solids of this layer have mean and metallic loads that are of the same order of magnitude as the eroded particles. Moreover, the mass of the organic layer considered over different time scales is of the same order of magnitude as the eroded masses during rainfall events and an erosion experiment showed that the organic layer is actually eroded.

[Research on pollution load of sediments in storm sewer in Beijing district].

PubMed

Li, Hai-Yan; Xu, Bo-Ping; Xu, Shang-Ling; Cui, Shuang

2013-03-01

Based on the investigation of sewer sediments in Xi Cheng district in Beijing, scour-release pollution load in one rainfall from sewer sediments was studied by monitoring the pollutants in the run-off of manhole's section. It was shown that the contribution of scour-release pollutants from sewer sediments to sewer outflow was obvious. The contribution rate of the sediments pollution load to runoff outflow in the 84 m pipeline in one rainfall (9 Jul., 2010) was as follows: TN 8.5%, TP 8.2%, COD 18.3%, SS 7.7%, respectively. And the pollutant contribution rate in the 295 m pipeline in another rainfall (4 Aug., 2010) was TN 23.12%, TP 60.01%, COD 33.78%, SS 31.89%. Therefore, it is important to control the pollution from sewer sediments for the improvement of water environment.

The distribution dynamics and desorption behaviour of mobile pharmaceuticals and caffeine to combined sewer sediments.

PubMed

Hajj-Mohamad, M; Darwano, H; Duy, S Vo; Sauvé, S; Prévost, M; Arp, H P H; Dorner, S

2017-01-01

Pharmaceuticals are discharged to the environment from wastewater resource recovery facilities, sewer overflows, and illicit sewer connections. To understand the fate of pharmaceuticals, there is a need to better understand their sorption dynamics to suspended sediments (SS) and settled sediments (StS) in sewer systems. In this study, such sorption dynamics to both SS and StS were assessed using a batch equilibrium method under both static and dynamic conditions. Experiments were performed with natively occurring and artificially modified concentrations of sewer pharmaceuticals (acetaminophen, theophylline, carbamazepine, and a metabolite of carbamazepine) and caffeine. Differences in apparent distribution coefficients, K d,app , between SS and StS were related to differences in their organic carbon (OC) content, and the practice of artificially modifying the concentration. K d,app values of modified contaminant concentrations and high OC sediments were substantially higher. Pseudo-second order desorption rates for these mobile compounds were also quantified. Successive flushing events to simulate the addition of stormwater to sewer networks revealed that aqueous concentrations would not necessarily decrease, because the added water will rapidly return to equilibrium concentrations with the sediments. Sorption and desorption kinetics must be considered in addition to dilution, to avoid underestimating the influence of dilution on concentrations of pharmaceuticals discharged to the environment. Copyright © 2016 Elsevier Ltd. All rights reserved.

SEWER SEDIMENT AND CONTROL: A MANAGEMENT PRACTICES REFERENCES GUIDE

EPA Science Inventory

Sewer-solids sediment is one of major sources of pollutants in urban wet-weather flow (WWF) discharges that include combined-sewer overflow (CSO), separate sanitary-sewer overflow (SSO), and stormwater runoff. During low-flow, dry-weather periods, sanitary wastewater solids depo...

HYDRAULIC CHARACTERISTICS OF SEWER SEDIMENT GATE FLUSHING TANKS: LABORATORY FLUME STUDIES

EPA Science Inventory

The objective of this study was to test the performance of gate flushing tanks, simulated in a laboratory flume, to remove sediments from combined sewers and storage tanks. A significant amount of sediment/debris/sludge may accumulate at the bottom of a sewer during dry weather o...

HYDRAULIC CHARACTERISTICS OF SEWER SEDIMENT GATE-FLUSHING TANKS: LABORATORY FLUME STUDIES

EPA Science Inventory

The objective of this study was to test the performance of gate-flushing tanks, simulated in a laboratory flume, to remove sediments from combined sewers and storage tanks. A significant amount of sediment/debris/sludge may accumulate at the bottom of a sewer during dry weather o...

Assessment of erosion and sedimentation dynamic in a combined sewer network using online turbidity monitoring.

PubMed

Bersinger, T; Le Hécho, I; Bareille, G; Pigot, T

2015-01-01

Eroded sewer sediments are a significant source of organic matter discharge by combined sewer overflows. Many authors have studied the erosion and sedimentation processes at the scale of a section of sewer pipe and over short time periods. The objective of this study was to assess these processes at the scale of an entire sewer network and over 1 month, to understand whether phenomena observed on a small scale of space and time are still valid on a larger scale. To achieve this objective the continuous monitoring of turbidity was used. First, the study of successive rain events allows observation of the reduction of the available sediment and highlights the widely different erosion resistance for the different sediment layers. Secondly, calculation of daily chemical oxygen demand (COD) fluxes during the entire month was performed showing that sediment storage in the sewer pipe after a rain period is important and stops after 5 days. Nevertheless, during rainfall events, the eroded fluxes are more important than the whole sewer sediment accumulated during a dry weather period. This means that the COD fluxes promoted by runoff are substantial. This work confirms, with online monitoring, most of the conclusions from other studies on a smaller scale.

Experimental study of hydraulics and sediment capture efficiency in catchbasins.

PubMed

Tang, Yangbo; Zhu, David Z; Rajaratnam, N; van Duin, Bert

2016-12-01

Catchbasins (also known as gully pot in the UK and Australia) are used to receive surface runoff and drain the stormwater into storm sewers. The recent interest in catchbasins is to improve their effectiveness in removing sediments in stormwater. An experimental study was conducted to examine the hydraulic features and sediment capture efficiency in catchbasins, with and without a bottom sump. A sump basin is found to increase the sediment capture efficiency significantly. The effect of inlet control devices, which are commonly used to control the amount of flow into the downstream storm sewer system, is also studied. These devices will increase the water depth in the catchbasin and increase the sediment capture efficiency. Equations are developed for predicting the sediment capture efficiency in catchbasins.

The erosion behaviour of biologically active sewer sediment deposits: observations from a laboratory study.

PubMed

Banasiak, Robert; Verhoeven, Ronny; De Sutter, Renaat; Tait, Simon

2005-12-01

The erosion behaviour of various fine-grained sediment deposits has been investigated in laboratory experiments. This work mainly focused on tests using sewer sediment in which strong biochemical reactions were observed during the deposit formation period. A small number of initial tests were conducted in which the deposits were made from mixtures of "clean" mineral and organic sediments. The erosion behaviour observed in these tests was compared with the erosion characteristics for sediments taken from deposits in a sewer. The impact of the biological processes on physical properties such as bulk density, water content, deposit structure and the erosive behaviour as a function of bed shear stress are quantified and discussed. Based on these observations it is believed that bio-processes weaken the strength of the in-pipe sediment deposits. A significantly weaker sediment surface layer was observed during deposition under quiescent oxygen-rich conditions. This resulted in a deposit with low shear strength which may be a cause of a first foul flush of suspended sediment when flow rates were increased. Comparison between tests with sewer sediments and the artificial representative surrogates suggested that the deposits of the later did not correctly simulate the depositional development and the resultant erosion patterns observed with the more bio-active sewer sediment.

SEWER SEDIMENT CONTROL: AN OVERVIEW OF THE EPA WET WEATHER FLOW (WWF) RESEARCH PROGRAM

EPA Science Inventory

This paper presents an overview of EPA WWF Research Program projects related to causes of sewer solids deposition and control methods that can prevent accumulation of sewer sediments. In particular, discussion will focus on the relationship of wastewater characteristics to flow ...

SEWER-SEDIMENT CONTROL: OVERVIEW OF AN EPA WET-WEATHER FLOW RESEARCH PROGRAM

EPA Science Inventory

This paper presents a historical overview of the sewer sediment control projects conducted by the Wet-Weather Flow Research Program of the USEPA. Research presented includes studies of the causes of sewer solids deposition and development/evaluation of control methods that can pr...

GATE AND VACUUM FLUSHING OF SEWER SEDIMENT: LABORATORY TESTING

EPA Science Inventory

The objective of this study was to test the performance of a traditional gate-flushing device and a newly-designed vacuum-flushing device in removing sediment from combined sewers and CSO storage tanks. A laboratory hydraulic flume was used to simulate a reach of sewer or storag...

SEWER SEDIMENT GATE AND VACUUM FLUSHING TANKS: LABORATORY FLUME STUDIES

EPA Science Inventory

The objective of this study was to test the performance of a traditional gate-flushing device and a newly designed vacuum-flushing device in removing sediments from combined sewers and CSO storage tanks. A laboratory hydraulic flune was used to simulate a reach of sewer or storag...

Automatic Vacuum Flushing Technology for Combined Sewer Solids: Laboratory Testing and Proposed Improvements (WERF Report INFR7SG09)

EPA Science Inventory

This research study included an extensive literature review on existing sewer sediment flushing technologies. An innovative vacuum flush system previously developed by the U.S. EPA was tested under laboratory conditions. The tests revealed a strong correlation between the strengt...

Development of a depth-integrated sample arm (DISA) to reduce solids stratification bias in stormwater sampling

USGS Publications Warehouse

Selbig, William R.; ,; Roger T. Bannerman,

2011-01-01

A new depth-integrated sample arm (DISA) was developed to improve the representation of solids in stormwater, both organic and inorganic, by collecting a water quality sample from multiple points in the water column. Data from this study demonstrate the idea of vertical stratification of solids in storm sewer runoff. Concentrations of suspended sediment in runoff were statistically greater using a fixed rather than multipoint collection system. Median suspended sediment concentrations measured at the fixed location (near the pipe invert) were approximately double those collected using the DISA. In general, concentrations and size distributions of suspended sediment decreased with increasing vertical distance from the storm sewer invert. Coarser particles tended to dominate the distribution of solids near the storm sewer invert as discharge increased. In contrast to concentration and particle size, organic material, to some extent, was distributed homogenously throughout the water column, likely the result of its low specific density, which allows for thorough mixing in less turbulent water.

Development of a depth-integrated sample arm to reduce solids stratification bias in stormwater sampling.

PubMed

Selbig, William R; Bannerman, Roger T

2011-04-01

A new depth-integrated sample arm (DISA) was developed to improve the representation of solids in stormwater, both organic and inorganic, by collecting a water quality sample from multiple points in the water column. Data from this study demonstrate the idea of vertical stratification of solids in storm sewer runoff. Concentrations of suspended sediment in runoff were statistically greater using a fixed rather than multipoint collection system. Median suspended sediment concentrations measured at the fixed location (near the pipe invert) were approximately double those collected using the DISA. In general, concentrations and size distributions of suspended sediment decreased with increasing vertical distance from the storm sewer invert. Coarser particles tended to dominate the distribution of solids near the storm sewer invert as discharge increased. In contrast to concentration and particle size, organic material, to some extent, was distributed homogenously throughout the water column, likely the result of its low specific density, which allows for thorough mixing in less turbulent water.

Development of a depth-integrated sample arm to reduce solids stratification bias in stormwater sampling

USGS Publications Warehouse

Selbig, W.R.; Bannerman, R.T.

2011-01-01

A new depth-integrated sample arm (DISA) was developed to improve the representation of solids in stormwater, both organic and inorganic, by collecting a water quality sample from multiple points in the water column. Data from this study demonstrate the idea of vertical stratification of solids in storm sewer runoff. Concentrations of suspended sediment in runoff were statistically greater using a fixed rather than multipoint collection system. Median suspended sediment concentrations measured at the fixed location (near the pipe invert) were approximately double those collected using the DISA. In general, concentrations and size distributions of suspended sediment decreased with increasing vertical distance from the storm sewer invert. Coarser particles tended to dominate the distribution of solids near the storm sewer invert as discharge increased. In contrast to concentration and particle size, organic material, to some extent, was distributed homogenously throughout the water column, likely the result of its low specific density, which allows for thorough mixing in less turbulent water. ?? 2010 Publishing Technology.

The influence of biodegradability of sewer solids for the management of CSOs.

PubMed

Sakrabani, R; Ashley, R M; Vollertsen, J

2005-01-01

The re-suspension of sediments in combined sewers and the associated pollutants into the bulk water during wet weather flows can cause pollutants to be carried further downstream to receiving waters or discharged via Combined Sewer Overflows (CSO). A typical pollutograph shows the trend of released bulk pollutants with time but does not consider information on the biodegradability of these pollutants. A new prediction methodology based on Oxygen Utilisation Rate (respirometric method) and Erosionmeter (laboratory device replicating in-sewer erosion) experiments is proposed which is able to predict the trends in biodegradability during in-sewer sediment erosion in wet weather conditions. The proposed new prediction methodology is also based on COD fractionation techniques.

Contribution of different sources to the pollution of wet weather flows in combined sewers.

PubMed

Gromaire, M C; Garnaud, S; Saad, M; Chebbo, G

2001-02-01

Experiments performed on "Marais" catchment, in central Paris, aimed to follow up the quality of wet weather flows from the entry to the exit of a combined sewer network. SS, VSS, COD, BOD5, Cd, Cu, Pb, Zn concentrations were measured for an important number of rain events in roof, yard, street runoff, as well as in dry and wet weather flows at the catchment outlet. Mass entry-exit totals, at the scale of the catchment, were calculated over 31 rain events in order to evaluate the contribution of different types of runoff, of sanitary sewage and of sewer sediments to the total wet weather pollutant loads at the catchment outlet. The erosion of in-sewer pollutant stocks was found to be the main source of particles and of organic matter in wet weather flows, whereas heavy metal loads mainly originated from roof runoff, due to the corrosion of metallic roofs. Particles eroded inside the sewer during rain events were found to be quite different from the particles constituting the main part of sewer sediments: they are organic and biodegradable, with rather important settling velocities and seem to accumulate during dry weather periods. A change of the chemical form of heavy metals was noticed during the transport in the sewer and it is suspected that a fraction of the dissolved metals from the runoff is adsorbed on sewer sediments.

Tidal river sediments in the Washington, D.C. area. 11. Distribution and sources of organic containmants

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wade, T.L.; Velinsky, D.J.; Reinharz, E.

1994-06-01

Concentrations of aliphatic, aromatic, and chlorinated hydrocarbons were determined from 33 surface-sediment samples taken from the Tidal Basin, Washington Ship Channel, and the Anacostia and Potomac rivers in Washington, D.C. In conjunction with these samples, selected storm sewers and outfalls also were sampled to help elucidate general sources of contamination to the area. All of the sediments contained detectable concentrations of aliphatic and aromatic hydrocarbons, DDT (total dichlorodiphenytrichloroethande), DDE (dichlorodiphenyldichloroethene), DDD (dichlorodiphenyldichloroethane), PCBx (total polychlorinated biphenyls) and total chlordanes (oxy-, {alpha}-, and {gamma}-chlordane and cis + trans-nonachlor). Sediment concentrations of most contaminants were highest in the Anacostia River just downstreammore » of the Washington Navy Yard, except for total chlordane, which appeared to have upstream sources in addition to storm and combined sewer runoff. This area has the highest number of storm and combined sewer outfalls in the river. Potomac River stations had lower concentrations than other stations. Polycyclic aromatic hydrocarbons, saturated hydrocarbons, and the unresolved complex mixture (UCM) distributions reflect mixtures of combustion products and direct discharges of petroleum products. Sources of PCBs appear to be related to specific outfalls, while hydrocarbon inputs, especially PAHs, are diffuse, and may be related to street runoff. This study indicates that in large urban areas, nonpoint sources deliver substantial amounts of contaminants to ecosystems through storm and combined sewer systems, and control of these inputs must be addressed. 33 refs., 6 figs., 3 tabs.« less

Estimation of sediments in urban drainage areas and relation analysis between sediments and inundation risk using GIS.

PubMed

Moojong, Park; Hwandon, Jun; Minchul, Shin

2008-01-01

Sediments entering the sewer in urban areas reduce the conveyance in sewer pipes, which increases inundation risk. To estimate sediment yields, individual landuse areas in each sub-basin should be obtained. However, because of the complex nature of an urban area, this is almost impossible to obtain manually. Thus, a methodology to obtain individual landuse areas for each sub-basin has been suggested for estimating sediment yields. Using GIS, an urban area is divided into sub-basins with respect to the sewer layout, with the area of individual landuse estimated for each sub-basin. The sediment yield per unit area for each sub-basin is then calculated. The suggested method was applied to the GunJa basin in Seoul. For a relation analysis between sediments and inundation risk, sub-basins were ordered by the sediment yields per unit area and compared with historical inundation areas. From this analysis, sub-basins with higher order were found to match the historical inundation areas. Copyright IWA Publishing 2008.

Acoustic measurement and morphological features of organic sediment deposits in combined sewer networks.

PubMed

Carnacina, Iacopo; Larrarte, Frédérique; Leonardi, Nicoletta

2017-04-01

The performance of sewer networks has important consequences from an environmental and social point of view. Poor functioning can result in flood risk and pollution at a large scale. Sediment deposits forming in sewer trunks might severely compromise the sewer line by affecting the flow field, reducing cross-sectional areas, and increasing roughness coefficients. In spite of numerous efforts, the morphological features of these depositional environments remain poorly understood. The interface between water and sediment remains inefficiently identified and the estimation of the stock of deposit is frequently inaccurate. In part, this is due to technical issues connected to difficulties in collecting accurate field measurements without disrupting existing morphologies. In this paper, results from an extensive field campaign are presented; during the campaign a new survey methodology based on acoustic techniques has been tested. Furthermore, a new algorithm for the detection of the soil-water interface, and therefore for the correct esteem of sediment stocks is proposed. Finally, results in regard to bed topography, and morphological features at two different field sites are presented and reveal that a large variability in bed forms is present along sewer networks. Copyright © 2017 Elsevier Ltd. All rights reserved.

Methane emission from sewers.

PubMed

Liu, Yiwen; Ni, Bing-Jie; Sharma, Keshab R; Yuan, Zhiguo

2015-08-15

Recent studies have shown that sewer systems produce and emit a significant amount of methane. Methanogens produce methane under anaerobic conditions in sewer biofilms and sediments, and the stratification of methanogens and sulfate-reducing bacteria may explain the simultaneous production of methane and sulfide in sewers. No significant methane sinks or methanotrophic activities have been identified in sewers to date. Therefore, most of the methane would be emitted at the interface between sewage and atmosphere in gravity sewers, pumping stations, and inlets of wastewater treatment plants, although oxidation of methane in the aeration basin of a wastewater treatment plant has been reported recently. Online measurements have also revealed highly dynamic temporal and spatial variations in methane production caused by factors such as hydraulic retention time, area-to-volume ratio, temperature, and concentration of organic matter in sewage. Both mechanistic and empirical models have been proposed to predict methane production in sewers. Due to the sensitivity of methanogens to environmental conditions, most of the chemicals effective in controlling sulfide in sewers also suppress or diminish methane production. In this paper, we review the recent studies on methane emission from sewers, including the production mechanisms, quantification, modeling, and mitigation. Copyright © 2015 Elsevier B.V. All rights reserved.

Field campaign on sediment transport behaviour in a pressure main from pumping station to wastewater treatment plant in Berlin.

PubMed

Gunkel, M; Pawlowsky-Reusing, E

2017-05-01

As part of the project KURAS, the Berliner Wasserbetriebe realized a field campaign in 2015 in order to increase the process knowledge regarding the behaviour of transported sediment in the pressure main leading from the pumpstation to the wastewater treatment plant. The field campaign was conducted because of a lack of knowledge about the general condition of the pressure main due to its bad accessibility and the suspicion of deposits caused by hydraulic underload. The practical evidence of the sediment transport performance of this part of the sewer system, dependent on different load cases, should present a basis for further analysis, for example regarding flushing measures. A positive side-effect of the investigation was the description of the amount of pollutants caused by different weather conditions in combined sewer systems and the alterations of the sewage composition due to biogenic processes during transport. The concept included the parallel sampling of the inflow at the pumpstation and the outflow at the end of the pressure main during different weather conditions. By calculating the inflow to the pressure main, as well as its outflow at different flow conditions, it was possible to draw conclusions in regard to the transport behaviour of sediment and the bioprocesses within an 8.5 km section of the pressure main. The results show clearly that the effects of sedimentation and remobilization depend on the flow conditions. The balance of the total suspended solids (TSS) load during daily variations in dry weather shows that the remobilization effect during the run-off peak is not able to compensate for the period of sedimentation happening during the low flow at night. Based on the data for dry weather, an average of 238 kg of TSS deposits in the pressure main remains per day. The remobilization of sediment occurs only due to the abruptly increased delivery rates caused by precipitation events. These high pollution loads lead to a sudden strain at the wastewater treatment plant. It was found that the sediment transport behaviour is characterized by sedimentation up to a flow velocity of 0.35 m/s, while remobilization effects occur above 0.5 m/s. The assumption of bad sediment transport performance in the pressure main was confirmed. Therefore, the results can be used as a basis for further analysis, for example regarding periodical flushing as a means of cleaning the pressure main. The findings, especially regarding the methods and processes, are transferable and can be applied to other pressure mains in combined sewer systems. Besides the outlined evaluation of the sediment transport behaviour of the pressure main, the collected data were used in the project to calibrate a sewer system model, including a water quality model for the catchment area, and as a contribution towards an early physically based sediment transport modelling in InfoWorks CS.

REMOVAL OF TANK AND SEWER SEDIMENT BY GATE FLUSHING: COMPUTATIONAL FLUID DYNAMICS MODEL STUDIES

EPA Science Inventory

This presentation will discuss the application of a computational fluid dynamics 3D flow model to simulate gate flushing for removing tank/sewer sediments. The physical model of the flushing device was a tank fabricated and installed at the head-end of a hydraulic flume. The fl...

Investigating the effect of storm events on the particle size distribution in a combined sewer simulator.

PubMed

Biggs, C A; Prall, C; Tait, S; Ashley, R

2005-01-01

The changes in particle size of sewer sediment particles rapidly eroded from a previously deposited sediment bed are described, using a rotating annular flume as a laboratory scale sewer simulator. This is the first time that particle size distributions of eroded sewer sediments from a previously deposited sediment bed have been monitored in such a controlled experimental environment. Sediments from Loenen, The Netherlands and Dundee, UK were used to form deposits in the base of the annular flume (WL Delft Netherlands) with varying conditions for consolidation in order to investigate the effect of changing consolidation time, temperature and sediment type on the amount and size of particles eroded from a bed under conditions of increasing shear. The median size of the eroded particles did not change significantly with temperature, although the eroded suspended solids concentration was greater for the higher temperature under the same shear stresses, indicating a weaker bed deposit. An increase in consolidation time caused an increase in median size of eroded solids at higher bed shear stresses, and this was accompanied by higher suspended solids concentrations. As the shear stress increased, the solids eroded from the bed developed under a longer consolidation time (56 hours) tended towards a broad unimodal distribution, whilst the size distribution of solids eroded from beds developed under shorter consolidation times (18 or 42 hours) retained a bi- or tri-modal distribution. Using different types of sediment in the flume had a marked effect on the size of particles eroded.

In situ observation of the water-sediment interface in combined sewers, using endoscopy.

PubMed

Oms, C; Gromaire, M C; Chebbo, G

2003-01-01

A new method for water-sediment interface observation has been designed. This system is based on a small diameter endoscope protected by a graduated plastic tube. It makes it possible to visualise in a non-destructive manner the sediments and the water-sediment interface. The endoscope was used to investigate Le Marais catchment (Paris): an immobile organic layer was observed at the water-sediment interface. This layer appears in pools of gross bed sediment, at the upstream of collectors, in zones where velocity is slow and where bed shear stress is less than 0.03 N/m2.

Pollutant removal from oily wastewater discharged from car washes through sedimentation-coagulation.

PubMed

Rubí, H; Fall, C; Ortega, R E

2009-01-01

Wastewater from car washes represents a potential problem for the sewer system due to its emulsified oils and suspended material. Treatment of wastewater discharged from four car washes was investigated by sedimentation and coagulation. The effect of the coagulants Servical P (aluminium hydroxychloride), Servican 50 (poly(diallyldimethylammonium chloride)), aluminium sulfate and ferric chloride was evaluated. The achieved removal using sedimentation was of 82%, 88% 73% and 51% for oils, total suspended solids, COD, and turbidity, respectively. In the treatment by coagulation we achieved average efficiencies nearly to 74% for COD removal, greater than 88% in the case of total suspended solids removal and 92% in the case of turbidity and except the performance of Servican 50 greater than 90% in oil removal. We concluded that the oil residual concentration and COD in the treated water allows pouring it in the sewer system complying with the limits of the Mexican rule NOM-002-ECOL-1996 and it is possible even its reuse, at least in the case of the chassis washing of cars.

Monitoring in inline storage sewers for stormwater treatment to determine efficiencies.

PubMed

Frehmann, T; Mietzel, T; Kutzner, R; Spengler, B; Geiger, W F

2004-01-01

A special structure of combined sewer overflow tanks is the inline storage sewer with downstream discharge (SKU). This layout has the advantage that besides the sewer system, no other structures are required for storm water treatment. Consequently only very little space is required and compared to combined sewer overflow tanks, there is an enormous potential in reducing costs during construction. To investigate the efficiency of an inline storage sewer, a monitoring station was established in Dortmund-Scharnhorst, Germany. The monitoring station was in operation for a period of 2.5 years. Within this period water samples were taken during a total of 20 discharge events. Besides the complete hydraulic data collection, seven water samplers took more than 5,000 water samples during dry and wet weather. This adds up to a total of more than 20,000 individual lab analyses. The average of the total efficiency for the SKU-West is 86%. 29% of this efficiency can be attributed to the throttle flow. The remaining 57% can be divided into a part of 48% that can be attributed to the process storage and 9% that can be attributed to sedimentation and erosion process.

Biodegradability of organic matter associated with sewer sediments during first flush.

PubMed

Sakrabani, Ruben; Vollertsen, Jes; Ashley, Richard M; Hvitved-Jacobsen, Thorkild

2009-04-01

The high pollution load in wastewater at the beginning of a rain event is commonly known to originate from the erosion of sewer sediments due to the increased flow rate under storm weather conditions. It is essential to characterize the biodegradability of organic matter during a storm event in order to quantify the effect it can have further downstream to the receiving water via discharges from Combined Sewer Overflow (CSO). The approach is to characterize the pollutograph during first flush. The pollutograph shows the variation in COD and TSS during a first flush event. These parameters measure the quantity of organic matter present. However these parameters do not indicate detailed information on the biodegradability of the organic matter. Such detailed knowledge can be obtained by dividing the total COD into fractions with different microbial properties. To do so oxygen uptake rate (OUR) measurements on batches of wastewater have shown itself to be a versatile technique. Together with a conceptual understanding of the microbial transformation taking place, OUR measurements lead to the desired fractionation of the COD. OUR results indicated that the highest biodegradability is associated with the initial part of a storm event. The information on physical and biological processes in the sewer can be used to better manage sediment in sewers which can otherwise result in depletion of dissolved oxygen in receiving waters via discharges from CSOs.

Sediment transport modeling in deposited bed sewers: unified form of May's equations using the particle swarm optimization algorithm.

PubMed

Safari, Mir Jafar Sadegh; Shirzad, Akbar; Mohammadi, Mirali

2017-08-01

May proposed two dimensionless parameters of transport (η) and mobility (F s ) for self-cleansing design of sewers with deposited bed condition. The relationships between those two parameters were introduced in conditional form for specific ranges of F s , which makes it difficult to use as a practical tool for sewer design. In this study, using the same experimental data used by May and employing the particle swarm optimization algorithm, a unified equation is recommended based on η and F s . The developed model is compared with original May relationships as well as corresponding models available in the literature. A large amount of data taken from the literature is used for the models' evaluation. The results demonstrate that the developed model in this study is superior to May and other existing models in the literature. Due to the fact that in May's dimensionless parameters more effective variables in the sediment transport process in sewers with deposited bed condition are considered, it is concluded that the revised May equation proposed in this study is a reliable model for sewer design.

Tidal river sediments in the Washington, D.C. area. 1. Distribution and sources of trace metals

DOE Office of Scientific and Technical Information (OSTI.GOV)

Velinsky, D.J.; Wade, T.L.; Schlekat, C.E.

1994-06-01

Thirty-three bottom sediments were collected from the Potomac and Anacostia rivers, Tidal Basin, and Washington Ship Channel in June 1991 to define the extent of trace metal contamination and to elucidate source areas of sediment contaminants. In addition, twenty-three sediment samples were collected directly in front of and within major storm and combined sewers that discharge directly to these areas. Trace metals (e.g., Cu, Crk Cd, Hg, Pb, and Zn) exhibited a wide range in values in the study area. Sediment concentrations of Pb ranged from 32.0{mu}g Pb g {sup -1} to 3,630 {mu}g Pb g{sup -1}, Cd from 0.24more » {mu}g Cd g{sup -1} to 4.1 {mu}g Cd g{sup -1}, and Hg from 0.13 {mu}g g{sup -1} to 9.2 {mu}g Hg g{sup -1}, with generally higher concentrations in either outfall or sewer sediments compared to river bottom-sediments. In the Anacostia River measurements indicate that numerous storm and combined sewers are major sources of trace metals. Similar results were observed in both the Tidal Basin and Washington Ship Channel. Cadmium and Pb concentrations are higher in specific sewers and outfalls, whereas the distribution of other metals suggests a more diffuse source to the rivers and basins of the area. Cadmium and Pb also exhibited the greatest enrichment throughout the study area, with peak values in the Anacostia River, near the Washington Navy Yard. Enrichment factors decrease in the order: Cd>Pb>Zn>Hg>Cu>Cr. Between 70% and 96% of sediment-bound Pb and Cd was released from a N{sub 2}-purged 1N HCI leach. On average, {le}40% of total sedimentary Cu was liberated, possibly due to the partial attack of organic components of the sediment. Sediments of the tidal freshwater portion of the Potomac estuary reflect moderate to highly contaminated area with substantial enrichments of sedimentary Pb, Cd, and Zn. The sediment phase containing these metals indicates potential mobility of the sediment-bound metals during either storm events or dredging. 39 refs., 5 figs., 6 tabs.« less

Total and settling velocity-fractionated pollution potential of sewer sediments in Jiaxing, China.

PubMed

Zhou, Yongchao; Zhang, Ping; Zhang, Yiping; Li, Jin; Zhang, Tuqiao; Yu, Tingchao

2017-10-01

Sewer sediments and their associated contaminant released along with wet-weather discharges pose potential pollution risks to environment. This paper presents total characteristics of sediments collected from Jiaxing, China. Size distribution and concentrations of volatile solids (VS) and four metals (Pb, Cu, Zn, Cr) of sediment samples from seven land use categories were analyzed. Then, the sediment samples were graded five fractions according to its settling velocity through the custom-built settling velocity-grading device. Sediment mass and pollution load distribution based on settling velocity were also assessed. The results show that there are relatively high level of heavy metal load in the sediment of separated storm drainage systems in Jiaxing, especially for the catchment of residential area (RA), road of developed area (RDA), and industrial area (IA). Although grain size follows a trend of increasing along with settling velocity, the methods of settling velocity grading are meaningful for stormwater treatment facilities with precipitation. For all land use categories, the pollution concentrations of the three lower settling velocity-fractionated sediment are relatively consistent and higher than others. Combined with mass distribution, the pollution percentage of fraction with different velocities for seven land use categories were also evaluated. Based on it, the statistical conclusion of design target settling velocity to different pollution load removal rates are drawn, which is helpful to guide design of on-site precipitation separation facilities.

Managing sewer solids for the reduction of foul flush effects--Forfar WTP.

PubMed

Fraser, A G; Sakrabani, R; Ashley, R M; Johnstone, F M

2002-01-01

In times of high sewer flow, conditions can exist which enable previously deposited material to be re-entrained back into the body of the flow column. Pulses of this highly polluted flow have been recorded in many instances at the recently constructed wastewater treatment plant (WTP) in Forfar, Scotland. Investigations have been undertaken to characterise the incoming flows and to suggest remedial measures to manage the quality fluctuations. Initial visits to the works and incoming pipes indicated a high degree of sediment deposition in the two inlet pipes. Analyses were carried out and consequently, changes to the hydraulic regime were made. Measurements of sediment level, sediment quality, wall slime and bulk water quality were monitored in the period following the remedial works to observe any improvements. Dramatic alterations in each of the determinands measured were recorded. Analyses were then undertaken to determine long term sediment behaviour and to assess the future usefulness of existing upstream sediment traps. It was concluded that with proper maintenance of the traps, the new hydraulic regime is sufficient to prevent further significant build up of sediment deposits and reduce impacts on the WTP. Further investigations made by North of Scotland Water Authority highlighted trade inputs to the system which may also have contributed to the now managed foul flush problem.

Design of a fuzzy differential evolution algorithm to predict non-deposition sediment transport

NASA Astrophysics Data System (ADS)

Ebtehaj, Isa; Bonakdari, Hossein

2017-12-01

Since the flow entering a sewer contains solid matter, deposition at the bottom of the channel is inevitable. It is difficult to understand the complex, three-dimensional mechanism of sediment transport in sewer pipelines. Therefore, a method to estimate the limiting velocity is necessary for optimal designs. Due to the inability of gradient-based algorithms to train Adaptive Neuro-Fuzzy Inference Systems (ANFIS) for non-deposition sediment transport prediction, a new hybrid ANFIS method based on a differential evolutionary algorithm (ANFIS-DE) is developed. The training and testing performance of ANFIS-DE is evaluated using a wide range of dimensionless parameters gathered from the literature. The input combination used to estimate the densimetric Froude number ( Fr) parameters includes the volumetric sediment concentration ( C V ), ratio of median particle diameter to hydraulic radius ( d/R), ratio of median particle diameter to pipe diameter ( d/D) and overall friction factor of sediment ( λ s ). The testing results are compared with the ANFIS model and regression-based equation results. The ANFIS-DE technique predicted sediment transport at limit of deposition with lower root mean square error (RMSE = 0.323) and mean absolute percentage of error (MAPE = 0.065) and higher accuracy ( R 2 = 0.965) than the ANFIS model and regression-based equations.

Long-term impacts on sewers following food waste disposer installation in housing areas.

PubMed

Mattsson, Jonathan; Hedström, Annelie; Viklander, Maria

2014-01-01

To increase biogas generation and decrease vehicle transportation of solid waste, the integration of food waste disposers (FWDs) into the wastewater system has been proposed. However, concerns have been raised about the long-term impact of the additional load of the FWDs on sewer systems. To examine the said impact, this study has used closed-circuit television inspection techniques to evaluate the status of 181 concrete pipes serving single family housing areas with a diameter of 225 mm, ranging from a 100% connection rate of households with an FWD to none. A minor study was also performed on a multi-family housing area, where mainly plastic pipes (200 mm) were used. The extent and distribution of deposits related to the ratio of FWDs, inclination and pipe sagging (backfalls) were ascertained by using linear regression and analysis of variance. The results showed that FWDs have had an impact on the level of deposits in the sewer, but this has, in turn, been of minor significance. With a high connection rate of FWDs upstream of a pipe, the extent of the total level of deposits, as well as finer sediments, was statistically determined to be greater. However, the majority of the deposits were observed to be small, which would suggest the impact of FWDs on sewer performance to be minor. As food waste not compatible with the FWD was seen in the sewers, educational campaigns could be beneficial to further lower the risks of sewer blocking.

Comparison of genetic algorithm and imperialist competitive algorithms in predicting bed load transport in clean pipe.

PubMed

Ebtehaj, Isa; Bonakdari, Hossein

2014-01-01

The existence of sediments in wastewater greatly affects the performance of the sewer and wastewater transmission systems. Increased sedimentation in wastewater collection systems causes problems such as reduced transmission capacity and early combined sewer overflow. The article reviews the performance of the genetic algorithm (GA) and imperialist competitive algorithm (ICA) in minimizing the target function (mean square error of observed and predicted Froude number). To study the impact of bed load transport parameters, using four non-dimensional groups, six different models have been presented. Moreover, the roulette wheel selection method is used to select the parents. The ICA with root mean square error (RMSE) = 0.007, mean absolute percentage error (MAPE) = 3.5% show better results than GA (RMSE = 0.007, MAPE = 5.6%) for the selected model. All six models return better results than the GA. Also, the results of these two algorithms were compared with multi-layer perceptron and existing equations.

Modelling sewer sediment deposition, erosion, and transport processes to predict acute influent and reduce combined sewer overflows and CO(2) emissions.

PubMed

Mouri, Goro; Oki, Taikan

2010-01-01

Understanding of solids deposition, erosion, and transport processes in sewer systems has improved considerably in the past decade. This has provided guidance for controlling sewer solids and associated acute pollutants to protect the environment and improve the operation of wastewater systems. Although measures to decrease combined sewer overflow (CSO) events have reduced the amount of discharged pollution, overflows continue to occur during rainy weather in combined sewer systems. The solution lies in the amount of water allotted to various processes in an effluent treatment system, in impact evaluation of water quality and prediction technology, and in stressing the importance of developing a control technology. Extremely contaminated inflow has been a serious research subject, especially in connection with the influence of rainy weather on nitrogen and organic matter removal efficiency in wastewater treatment plants (WWTP). An intensive investigation of an extremely polluted inflow load to WWTP during rainy weather was conducted in the city of Matsuyama, the region used for the present research on total suspended solid (TSS) concentration. Since the inflow during rainy weather can be as much as 400 times that in dry weather, almost all sewers are unsettled and overflowing when a rain event is more than moderate. Another concern is the energy consumed by wastewater treatment; this problem has become important from the viewpoint of reducing CO(2) emissions and overall costs. Therefore, while establishing a prediction technology for the inflow water quality characteristics of a sewage disposal plant is an important priority, the development of a management/control method for an effluent treatment system that minimises energy consumption and CO(2) emissions due to water disposal is also a pressing research topic with regards to the quality of treated water. The procedure to improve water quality must make use of not only water quality and biotic criteria, but also modelling systems to enable the user to link the effect of changes in urban sewage systems with specific quality, energy consumption, CO(2) emission, and ecological improvements of the receiving water.

Impacts of sewer deposits on the urban river sediment after rainy season and bioremediation of polluted sediment.

PubMed

Chang, Suyun; Tang, Yinqi; Dong, Lixin; Zhan, Qiang; Xu, Wei

2018-05-01

Impacts of deposits discharged from a municipal pipe on urban river sediment were investigated in the Hucang River in Tianjin, China. At the outlet of the pump station, the average concentrations of total nitrogen (TN), total phosphorus (TP), and total organic carbon (TOC) in the sediment increased sharply from 2390, 799, and 14,600 mg/kg to 6500, 3700, and 153,000 mg/kg, respectively, and remained stable at high level after the rainy season. A portion of pollutants would migrate along the river, and the concentration was usually in a negative relationship with the distance. The average Shannon-Wiener value on the upstream section was higher than those on the downstream sections. This revealed that the deposits discharged decreased the bacterial diversity in the sediment, and high concentrations of pollutants may markedly change the bacterial community structure in the sediment. To reduce the pollution of the urban river after rainy season, four kinds of microbial consortiums A (Zhangda), B (Aiersi), C (Qinghe), and D (Inpipe) were applied to bioremediate the polluted sediment in lab scale. Bioaugmentation with microbial consortium A showed good performance on the bioremediation of the polluted sediment. The average removal efficiency of TN, TP, and organic matter reached 35.5, 43.7, and 39.1%, respectively, after 22 days of treatment. Moreover, the bacterial evenness and diversity in the sediment markedly increased, indicating that the microbial environment was more favourable after bioaugmentation and sustainable development would be guaranteed. This study improves our understanding of the impacts of deposits discharged from a stormwater drain system on urban river sediment, and explores the effectiveness of bioaugmentation for the bioremediation of polluted sediment, which will provide the basis of sewer deposit pollution control.

Trace element carriers in combined sewer during dry and wet weather: an electron microscope investigation.

PubMed

El Samrani, A G; Lartiges, B S; Ghanbaja, J; Yvon, J; Kohler, A

2004-04-01

The nature of trace element carriers contained in sewage and combined sewer overflow (CSO) was investigated by TEM-EDX-Electron diffraction and SEM-EDX. During dry weather, chalcophile elements were found to accumulate in sewer sediments as early diagenetic sulfide phases. The sulfurization of some metal alloys was also evidenced. Other heavy metal carriers detected in sewage include metal alloys, some iron oxihydroxide phases and neoformed phosphate minerals such as anapaite. During rain events, the detailed characterization of individual mineral species allowed to differentiate the contributions from various specific sources. Metal plating particles, barite from automobile brake, or rare earth oxides from catalytic exhaust pipes, originate from road runoff, whereas PbSn alloys and lead carbonates are attributed to zinc-works from roofs and paint from building siding. Soil contribution can be traced by the presence of clay minerals, iron oxihydroxides, zircons and rare earth phosphates. However, the most abundant heavy metal carriers in CSO samples were the sulfide particles eroded from sewer sediments. The evolution of relative abundances of trace element carriers during a single storm event, suggests that the pollution due to the "first flush" effect principally results from the sewer stock of sulfides and previously deposited metal alloys, rather than from urban surface runoff.

SEDIMENT TOXICITY AND STORMWATER RUNOFF IN A CONTAMINATED RECEIVING SYSTEM: CONSIDERATION OF DIFFERENT BIOASSAYS IN THE LABORATORY AND FIELD. (R823873)

EPA Science Inventory

Several field and laboratory assays were employed below an urban storm sewer outfall to define the relationship between stormwater runoff and contaminant effects. Specifically, two bioassays that measure feeding rate as a toxicological endpoint were employed in the field and in t...

Temporal Trends of Triclosan Contamination in Dated Sediment Cores from Four Urbanized Estuaries: Evidence of Preservation and Accumulation

EPA Science Inventory

Triclosan is an antimicrobial agent added to a wide array of consumer goods and personal care products. Through its use, it is introduced into municipal sewer systems where it is only partially removed during wastewater treatment with the balance entering receiving waters via ef...

Modelling the influence of total suspended solids on E. coli removal in river water.

PubMed

Qian, Jueying; Walters, Evelyn; Rutschmann, Peter; Wagner, Michael; Horn, Harald

2016-01-01

Following sewer overflows, fecal indicator bacteria enter surface waters and may experience different lysis or growth processes. A 1D mathematical model was developed to predict total suspended solids (TSS) and Escherichia coli concentrations based on field measurements in a large-scale flume system simulating a combined sewer overflow. The removal mechanisms of natural inactivation, UV inactivation, and sedimentation were modelled. For the sedimentation process, one, two or three particle size classes were incorporated separately into the model. Moreover, the UV sensitivity coefficient α and natural inactivation coefficient kd were both formulated as functions of TSS concentration. It was observed that the E. coli removal was predicted more accurately by incorporating two particle size classes. However, addition of a third particle size class only improved the model slightly. When α and kd were allowed to vary with the TSS concentration, the model was able to predict E. coli fate and transport at different TSS concentrations accurately and flexibly. A sensitivity analysis revealed that the mechanisms of UV and natural inactivation were more influential at low TSS concentrations, whereas the sedimentation process became more important at elevated TSS concentrations.

Sediments from stormwater drainage system as sorbents of organic and inorganic pollutants

NASA Astrophysics Data System (ADS)

Sałata, Aleksandra; Dąbek, Lidia

2017-11-01

The study presents the results of tests aimed at determining variations in concentrations of polycyclic aromatic hydrocarbons (naphthalene, acenaphthylene, acenaphthene, fluorene, phenanthrene, anthracene, fluoranthene, pyrene, benzo[a]anthracene, chrysene, benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[a]pyrene, dibenzo[a, h]anthracene, benzo[g, h, i]perylene and indeno[1, 2, 3-c, d]pyrene) and heavy metals (copper, cadmium, chromium, nickel, lead and zinc) in the sediments from the stormwater sewer system. Results of this study were then compared to Polish regulations and established ecological screening values to determine their potential risk to environment. The results suggest that stormwater sediments are moderately contaminated with PAHs and heavy metals according to domestic regulations and highly contaminated according to ecological benchmarks.

STORAGE/SEDIMENTATION FACILITIES FOR CONTROL OF STORM AND COMBINED SEWER OVERFLOW: DESIGN MANUAL

EPA Science Inventory

This manual describes applications of storage facilities in wet-weather flow management and presents step-by-step procedures for analysis and design of storage-treatment facilities. Retention, detention, and sedimentation storage information is classified and described. Internati...

The nature and pollutant role of solids at the water-sediment interface in combined sewer networks.

PubMed

Chebbo, G; Ashley, R; Gromaire, M C

2003-01-01

Solids at the water-sediment interface in combined sewers are known to be important for pollution potential during storm washout via CSOs. They have been investigated in several studies, but nonetheless, little is known about the origins, build-up, transport and nature of these solids. From a review of current knowledge it is apparent that whilst there is general agreement that these solids are largely organic and have high polluting potential, their modes of transport and definition are not generally agreed upon. It is possible that there may be several "types" of these solids, defined as either: "near bed solids" or "fluid sediments/dense undercurrents", possibly representing transport modes in flows with different ranges of ambient (dry weather) velocities and with differing sewerage layouts. Current knowledge is presented and new ideas for resolving the uncertainties regarding the nature, movement and effects of this material are outlined.

Sedimentology, stratigraphy and chronology of a decantation tank in the sewer network of Orléans (France).

NASA Astrophysics Data System (ADS)

Jacob, Jérémy; Thibault, Alexandre; Simonneau, Anaëlle; Le Milbeau, Claude; DiGiovanni, Christian; Sabatier, Pierre; Reyss, Jean-Louis; Ardito, Luigi; Morio, Cédric

2017-04-01

Current debates on the status of the Anthropocene convey geologists and palaeoenvironmentalists toward new spatial and temporal targets. One of the most emblematic socio-ecosystem of the Anthropocene is urban areas in which the dynamics of materials are mainly controlled by human activities. This brings unprecedented elemental, molecular and isotopic concentrations and distributions that lead Norra (2009) to propose a new geological sphere: the Astysphere. Here we propose that sediments accumulated in sewer networks can provide original, integrated, and multi-thematic archives for the recent history of cities by considering urban systems as any catchment where materials are produced, transported and sedimented. The study site is a decantation tank that collects stormwater and wastewater from the north of Orléans city, upstream wastewater plants in Orléans. Sediments accumulated since 1942 over 17 m depth and were never cleaned out until 2015. Two sedimentary cores of 70 (A) and 250 cm long (B) were collected before clean out and then a third of 150 cm (C) after. Sediments are organized into layers constituted by sands and gravels alternating with silts and organic layers. Sharp contacts between those layers indicate evenemential sedimentation, as expected in sewer networks. We formulate the hypothesis that organic/mineral alternations result from a seasonal dynamic. 7Be presence in topmost sample from core A confirms it was deposited within the last 6 months. In core C, only the upper half core, mostly mineral, displays significant 7Be levels whereas 7Be is absent from the lower half, which is mostly organic. This would confirm that our hypothesis of a seasonal alternation, with organic facies deposited during spring- summer and mineral facies deposited during fall-winter. 30 14C dates measured on cores A and B by postbomb method are logically distributed with depth, the most ancient (beginning of the eighties) being recorder at 2.5m depth. This study shows that sediments accumulated in a decantation tank constitute sedimentary archives comparable to more natural ones, thus allowing palaeoenvironmental reconstructions for the Anthropocene. We are currently examining the mineral and organic content of this archive to provide a detailed chronology of the history of man-made materials (drugs, plastics, pesticides…) in urban contexts.

Impacts of land use on phosphorus transport in a river system

NASA Astrophysics Data System (ADS)

Wang, J.; Pant, H. K.

2010-12-01

Phosphorus (P) is a primary limiting nutrient in freshwater systems, however, excessive P load in the systems cause eutriphication, resulting in algal blooms and oxygen depletion. This study estimated potential exchange of P between water column and sediments by P sorption, and identified P compounds in sediments by 31Phosphorus Nuclear Magnetic Resonance Spectroscopy in the samples collected from the Bronx River, New York City, NY. Similarly, mineralization, as well as enzymatic hydrolysis using native phosphoatases (NPase) and phosphodiesterase (PDEase) showed that land use changes and other anthropogenic factors had effects on the P availability in the river. Distinguished characteristics of P bioavailability appeared at major tributaries of Sprain Brook and Troublesome Brook, boundary between fresh and saline water at East Tremont Ave, and estuary close to Hunts Point Wastewater Treatment Plant. Incidental sewer overflows at Yonkers, oil spill at East Tremont Avenue Bridge, fertilizer application at Westchester’s lawns, and gardens, animal manure from the zoo, combined sewer overflows (CSOs), storm water runoff from Bronx River Parkway, and inputs from East River influenced spatial and temporal variations on P transport in the river. This study provides an overview of impacts of land use on nutrient transport in a river system, which may help to make effective policies to regulate P application in the river watersheds, in turn, improve water quality and ecological restoration of a river.

40 CFR 35.927-2 - Sewer system evaluation survey.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 1 2013-07-01 2013-07-01 false Sewer system evaluation survey. 35.927... § 35.927-2 Sewer system evaluation survey. (a) The sewer system evaluation survey shall identify the... results of the sewer system evaluation survey. In addition, the report shall include: (1) A justification...

40 CFR 35.927-2 - Sewer system evaluation survey.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 1 2010-07-01 2010-07-01 false Sewer system evaluation survey. 35.927... § 35.927-2 Sewer system evaluation survey. (a) The sewer system evaluation survey shall identify the... results of the sewer system evaluation survey. In addition, the report shall include: (1) A justification...

40 CFR 35.927-2 - Sewer system evaluation survey.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 1 2011-07-01 2011-07-01 false Sewer system evaluation survey. 35.927... § 35.927-2 Sewer system evaluation survey. (a) The sewer system evaluation survey shall identify the... results of the sewer system evaluation survey. In addition, the report shall include: (1) A justification...

40 CFR 35.927-2 - Sewer system evaluation survey.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 1 2012-07-01 2012-07-01 false Sewer system evaluation survey. 35.927... § 35.927-2 Sewer system evaluation survey. (a) The sewer system evaluation survey shall identify the... results of the sewer system evaluation survey. In addition, the report shall include: (1) A justification...

Assessment of 1-chloro-4-[2,2-dichloro-1-(4-chlorophenyl)ethenyl]benzene (DDE) Transformation Rates on the Palos Verdes Shelf, CA

USGS Publications Warehouse

Eganhouse, Robert P.; Pontolillo, James

2008-01-01

In 1953, the world's largest producer of DDT, Montrose Chemical Corporation, began to discharge process wastes into sewers of the Los Angeles County Sanitation Districts (LACSD), California. By 1971, when the sewer connection was terminated, approximately 1,500-2,000 metric tons of DDT had been introduced to the LACSD treatment plant in Carson, CA. After treatment, effluent from this plant was released to the ocean through a submarine outfall system on the Palos Verdes Shelf (PVS) near Los Angeles, resulting in the accumulation of highly contaminated marine sediments. Numerous investigations of the PVS have been undertaken since the late 1960s, but few have focused on the biogeochemical fate of DDT and its transformation products. In the early 1990s, it was shown that DDE, the major DDT compound in the sediments, was being reductively dechlorinated by microorganisms resident in sediments on the PVS. The U.S. Geological Survey undertook a study in cooperation with the U.S. Environmental Protection Agency to provide a better understanding of the range of reductive dechlorination rates on the PVS and the environmental factors that control them. Existing data show that rates of reductive dechlorination are variable spatially. A comparison of data from two cores collected approximately 7 kilometers downcurrent from the outfall systems in 1992 and 2003 yielded an average first-order transformation rate of approximately 0.05 yr-1. A multistep reaction model suggests that inventories of DDE in PVS sediments at the study site will continue to decline, whereas the inventory of the metabolite DDNU will reach a maximum around 2014.

Transformation of heavy metal fractionation under changing environments: a case study of a drainage system in an e-waste dismantling community.

PubMed

Damrongsiri, Seelawut

2018-04-01

The change in environmental conditions during the transportation of contaminated soil and sediment was expected to affect the transformation of heavy metal fractionation. This study disclosed the serious contamination of copper (Cu), lead (Pb), and zinc (Zn) in the sewer sediment of an e-waste dismantling community in Thailand which may be caused by flushed contaminated soil and e-waste fragments. Two environmental conditions were simulated to observe the transformation of heavy metal fractionation. The anoxic sewer condition was induced using high substrate and sulfate in a closed container. The aeration of anoxic contaminated sediment was applied to simulate the transformation to an oxidative environment. The BCR sequential extraction was applied for heavy metal fractionation in this study. The study results exhibited that when heavy metal contaminated soil was transferred into this induced anoxic condition, fractionation was redistributed based on the chemical change of system that tends to be associated into F3 (oxidizable fraction) > F2 (reducible fraction) > F1 (acid soluble/exchangeable fraction). Cu exhibited the outstanding capability association to F3. The iron sulfide was not observed as usual due to its lower capability than Cu, Pb, and Zn. When contaminated sediment was transported to a more oxidative environment, the heavy metals fractionation would be redistributed again among those new environment media. It is noteworthy that F3 of Cu was stable even in oxic conditions. F2 of Fe was not developed by this oxic condition, possibly because its dehydration process was limited. The redistribution under an oxic environment became F1 > F2 > F3 indicating their more available form. This transformation was imperative and should be taken into account in heavy metal contaminated site management and control.

Feasibility of sulfide control in sewers by reuse of iron rich drinking water treatment sludge.

PubMed

Sun, Jing; Pikaar, Ilje; Sharma, Keshab Raj; Keller, Jürg; Yuan, Zhiguo

2015-03-15

Dosage of iron salt is the most commonly used method for sulfide control in sewer networks but incurs high chemical costs. In this study, we experimentally investigate the feasibility of using iron rich drinking water treatment sludge for sulfide control in sewers. A lab-scale rising main sewer biofilm reactor was used. The sulfide concentration in the effluent decreased from 15.5 to 19.8 mgS/L (without dosing) to below 0.7-2.3 mgS/L at a sludge dosing rate achieving an iron to total dissolved inorganic sulfur molar ratio (Fe:S) of 1:1, with further removal of sulfide possible by prolonging the reaction time. In fact, batch tests revealed an Fe consumption to sulfide removal ratio of 0.5 ± 0.02 (mole:mole), suggesting the possible occurrence of other reactions involving the removal of sulfide. Modelling revealed that the reaction between iron in sludge and sulfide has reaction orders of 0.65 ± 0.01 and 0.77 ± 0.02 with respect to the Fe and sulfide concentrations, respectively. The addition of sludge slightly increased the total chemical oxidation demand (tCOD) concentration (by approximately 12%) as expected, but decreased the soluble chemical oxidation demand (sCOD) concentration and methane formation by 7% and 20%, respectively. Some phosphate removal (13%) was also observed at the sludge dosing rate of 1:1 (Fe:S), which is beneficial to nutrient removal from the wastewater. Overall, this study suggests that dosing iron-rich drinking water sludge to sewers could be an effective strategy for sulfide removal in sewer systems, which would also reduce the sludge disposal costs for drinking water treatment works. However, its potential side-effects on sewer sedimentation and on the wastewater treatment plant effluent remain to be investigated. Copyright © 2015 Elsevier Ltd. All rights reserved.

Priority pollutants in urban stormwater: part 1 - case of separate storm sewers.

PubMed

Zgheib, Sally; Moilleron, Régis; Chebbo, Ghassan

2012-12-15

Organic and mineral pollutants have become part of today's urban environment. During a rain event, stormwater quality as well as the corresponding contaminant loads is affected by both atmospheric deposition and the various types of impervious surfaces (roads, rooftops, parking lots etc.) on which runoff occurs. This study provides results on stormwater pollution in Paris and its suburbs from three separate storm sewers (n=20 samples). These results show that the stormwater had been contaminated by 55 chemical substances out of the 88 investigated. A particular attention was given to stormwater particle contamination. Concentrations are provided for: metals, PAHs, PCBs, organotins, alkylphenols, phthalates, pesticides, and VOCs. Our findings are among the first available in the literature since the relevant analyses were all conducted on both the particulate (P) and dissolved (D) phases. For most substances, particles from the three storm sewers were more heavily contaminated than dredged sediments and settleable particles from the Seine River. As a consequence of this finding, the release of untreated stormwater discharges may impact the receiving waters and contribute to sediment contamination. Copyright © 2011 Elsevier Ltd. All rights reserved.

On the preventive management of sediment-related sewer blockages: a combined maintenance and routing optimization approach.

PubMed

Fontecha, John E; Akhavan-Tabatabaei, Raha; Duque, Daniel; Medaglia, Andrés L; Torres, María N; Rodríguez, Juan Pablo

In this work we tackle the problem of planning and scheduling preventive maintenance (PM) of sediment-related sewer blockages in a set of geographically distributed sites that are subject to non-deterministic failures. To solve the problem, we extend a combined maintenance and routing (CMR) optimization approach which is a procedure based on two components: (a) first a maintenance model is used to determine the optimal time to perform PM operations for each site and second (b) a mixed integer program-based split procedure is proposed to route a set of crews (e.g., sewer cleaners, vehicles equipped with winches or rods and dump trucks) in order to perform PM operations at a near-optimal minimum expected cost. We applied the proposed CMR optimization approach to two (out of five) operative zones in the city of Bogotá (Colombia), where more than 100 maintenance operations per zone must be scheduled on a weekly basis. Comparing the CMR against the current maintenance plan, we obtained more than 50% of cost savings in 90% of the sites.

Characterization of runoff from various urban catchments at different spatial scales in Beijing, China.

PubMed

Zhang, W; Che, W; Liu, D K; Gan, Y P; Lv, F F

2012-01-01

In order to investigate the characterization of runoff in storm sewer from various urban catchments, three monitoring systems at different spatial scales have been installed separately. They have been held since July 2010 in urban area of Beijing (China). The monitoring data revealed that chemical oxygen demand (COD), total suspended solids (TSS), total nitrogen (TN), total phosphorus (TP), and NH(3)-N values significantly exceed the Class V surface water quality standard developed by Ministry of Environmental Protection of the People's Republic of China (MEP). A surface solids buildup and wash off model for small watershed was adopted to analyze and discuss the process of a runoff pollutant discharge. More than a half of pollutant parameters presented a good fit to the model. However, a slightly worse-fit to the wash off model appeared in less than half of the data. Due to the influence of sewer sediments, sewer system characteristics, catchment characteristics, and other reasons, first flush was seldom observed in storm sewer runoff from these three survey areas. Meanwhile, the correlation between TSS and any other pollutant was analyzed according to cumulative load of pollutants in runoff events. An event mean concentrations (EMCs) approach was adopted to quantify the pollution of runoff. EMCs of various pollutants in storm sewer runoff between different rainfall events were slightly higher than the typical values observed in similar areas at home and abroad, according to other studies reported in literature. Based on quantitative analysis, it can be concluded that urban non-point source pollution is recognized as the major causes of quality deterioration in the receiving water bodies. This is after the point source pollution has been controlled substantially in Beijing. An integrated strategy, which combines centralized and decentralized control, along with the conditions of meteorology, hydrology, urban planning, existing drainage system, etc., will be an effective and economic approach to urban runoff pollution control.

Effects of in-sewer processes: a stochastic model approach.

PubMed

Vollertsen, J; Nielsen, A H; Yang, W; Hvitved-Jacobsen, T

2005-01-01

Transformations of organic matter, nitrogen and sulfur in sewers can be simulated taking into account the relevant transformation and transport processes. One objective of such simulation is the assessment and management of hydrogen sulfide formation and corrosion. Sulfide is formed in the biofilms and sediments of the water phase, but corrosion occurs on the moist surfaces of the sewer gas phase. Consequently, both phases and the transport of volatile substances between these phases must be included. Furthermore, wastewater composition and transformations in sewers are complex and subject to high, natural variability. This paper presents the latest developments of the WATS model concept, allowing integrated aerobic, anoxic and anaerobic simulation of the water phase and of gas phase processes. The resulting model is complex and with high parameter variability. An example applying stochastic modeling shows how this complexity and variability can be taken into account.

Searching for storm water inflows in foul sewers using fibre-optic distributed temperature sensing.

PubMed

Schilperoort, Rémy; Hoppe, Holger; de Haan, Cornelis; Langeveld, Jeroen

2013-01-01

A major drawback of separate sewer systems is the occurrence of illicit connections: unintended sewer cross-connections that connect foul water outlets from residential or industrial premises to the storm water system and/or storm water outlets to the foul sewer system. The amount of unwanted storm water in foul sewer systems can be significant, resulting in a number of detrimental effects on the performance of the wastewater system. Efficient removal of storm water inflows into foul sewers requires knowledge of the exact locations of the inflows. This paper presents the use of distributed temperature sensing (DTS) monitoring data to localize illicit storm water inflows into foul sewer systems. Data results from two monitoring campaigns in foul sewer systems in the Netherlands and Germany are presented. For both areas a number of storm water inflow locations can be derived from the data. Storm water inflow can only be detected as long as the temperature of this inflow differs from the in-sewer temperatures prior to the event. Also, the in-sewer propagation of storm and wastewater can be monitored, enabling a detailed view on advection.

Locations of Combined Sewer Overflow Outfalls - US EPA Region 3

EPA Pesticide Factsheets

This data layer identifies the locations of Combined sewer overflow outfalls. Combined sewer systems are sewers that are designed to collect rainwater runoff, domestic sewage, and industrial wastewater in the same pipe. Most of the time, combined sewer systems transport all of their wastewater to a sewage treatment plant, where it is treated and then discharged to a water body. During periods of heavy rainfall or snowmelt, however, the wastewater volume in a combined sewer system can exceed the capacity of the sewer system or treatment plant. For this reason, combined sewer systems are designed to overflow occasionally and discharge excess untreated wastewater directly to nearby streams, rivers, or other water bodies. For further information visit: http://cfpub1.epa.gov/npdes/home.cfm?program_id=5

The behavior of natural and anthropogenic osmium in Long Island Sound, an urban estuary in the eastern U.S.

NASA Astrophysics Data System (ADS)

Williams, Gwyneth; Marcantonio, Franco; Turekian, Karl K.

1997-04-01

The Os concentration and 187Os/ 186Os distributions in surface sediments of Long Island Sound (eastern U.S.) provide a way of determining the sources and estuarine transport of Os. The contribution of anthropogenic Os from sewer outfalls from the New York City region supplies a tracer with a characteristic 187Os/ 186Os of about 1. The Os concentration of the bulk surface sediment increases steeply moving toward New York City in the westernmost Sound and generally follows the concentration of organic carbon. The 187Os/ 186Os ratio of bulk surface sediment increases from west to east in the westernmost part of the Sound and is effectively constant in the central Sound. We interpret these results as indicating that the surface bulk sediments of the Sound contain a low 187Os/ 186Os component, perhaps as a reduced coating associated with organic remains from sewer outfalls. The acid hydrogen peroxide leach fraction has an average 187Os/ 186Os of 9.5 in the central Sound, significantly higher than both the bulk sediment value and the probable sea water value of about 8. The leach fraction in the westernmost part of the traverse is less radiogenic than the central Sound and follows the Os wsotope trend of the bulk sediment. Liquid effluent from a New York City sewer outfall contains 30 pg l -1 of dissolved Os with a 187Os/ 186Os of about 2.5, consistent with its being an end-member of the west-east sediment pattern recorded in the leach fractions of the westernmost cores. The leachable Os from the central Sound predominantly reflects Os in ferromanganese oxyhydroxide coatings from continentally derived sediments with 187Os/ 186Os ratios more radiogenic than seawater. The distribution patterns of anthropogenic and natural Os, with their characteristic isotopic signatures in the Sound, and the insights gained from the behavior of other particle-reactive species, indicates that very little Os in solution may pass through the estuarine gauntlet.

Final Environmental Assessment Airfield Storm Drainage System Repair Joint Base Andrews-Naval Air Facility Washington, MD

DTIC Science & Technology

2015-06-01

sediment control plan during project implementation would be expected to minimize any adverse effects on resident fish species during construction. In... Effective August 8, 2007, under the authority of the Endangered Species Act of 1973, as amended, the U.S. Fish and Wildlife Service (Service) removed...of storm sewer pipe and 122 manholes of the airfield stormwater drainage network. Summary of Anticipated Environmental Effects Associated with the

Contributions of wastewater, runoff and sewer deposit erosion to wet weather pollutant loads in combined sewer systems.

PubMed

Gasperi, J; Gromaire, M C; Kafi, M; Moilleron, R; Chebbo, G

2010-12-01

An observatory of urban pollutants was created in Paris for the purpose of assessing the dynamics of wastewater and wet weather flow (WW and WWF) pollutant loads within combined sewers. This observatory is composed of six urban catchments, covering land areas ranging in size from 42 ha to 2581 ha. For a wide array of parameters including total suspended solids (TSS), chemical and biochemical oxygen demand (COD and BOD(5)), total organic carbon (TOC), total Kjeldahl nitrogen (TKN), heavy metals (Cu and Zn) and polycyclic aromatic hydrocarbons (PAHs), this article is intended to evaluate the contributions of wastewater, runoff and in-sewer processes to WWF pollutant loads through the use of an entry-exit mass balance approach. To achieve this objective, a total of 16 rain events were sampled on these sites between May 2003 and February 2006. This study has confirmed that at the considered catchment scale (i.e. from 42 ha to 2581 ha) the production and transfer processes associated with WWF pollutant loads do not vary with basin scale. Entry-exit chemical mass balances over all catchments and for a large number of rain events indicate that wastewater constitutes the main source of organic and nitrogenous pollution, while runoff is the predominant source of Zn. For Cu, PAHs and TSS, the calculation underscores the major role played by in-sewer processes, specifically by sediment erosion, as a source of WWF pollution. A significant loss of dissolved metals was also observed during their transfer within the sewer network, likely as a consequence of the adsorption of dissolved metals on TSS and/or on sewer deposits. Moreover, the nature of eroded particles was examined and compared to the various sewer deposits. This comparison has highlighted that such particles exhibit similar organic and PAH contents to those measured in the organic layer, thus suggesting that the deposit eroded during a wet weather period is organic and of a nature comparable to the organic layer. Despite the extent of initial field investigations, no organic deposit was observed to be present on sewer lines within the catchments, which implies that this organic deposit is probably present in another form or to be found elsewhere in the main trunks. Copyright © 2010 Elsevier Ltd. All rights reserved.

Integrating retention soil filters into urban hydrologic models - Relevant processes and important parameters

NASA Astrophysics Data System (ADS)

Bachmann-Machnik, Anna; Meyer, Daniel; Waldhoff, Axel; Fuchs, Stephan; Dittmer, Ulrich

2018-04-01

Retention Soil Filters (RSFs), a form of vertical flow constructed wetlands specifically designed for combined sewer overflow (CSO) treatment, have proven to be an effective tool to mitigate negative impacts of CSOs on receiving water bodies. Long-term hydrologic simulations are used to predict the emissions from urban drainage systems during planning of stormwater management measures. So far no universally accepted model for RSF simulation exists. When simulating hydraulics and water quality in RSFs, an appropriate level of detail must be chosen for reasonable balancing between model complexity and model handling, considering the model input's level of uncertainty. The most crucial parameters determining the resultant uncertainties of the integrated sewer system and filter bed model were identified by evaluating a virtual drainage system with a Retention Soil Filter for CSO treatment. To determine reasonable parameter ranges for RSF simulations, data of 207 events from six full-scale RSF plants in Germany were analyzed. Data evaluation shows that even though different plants with varying loading and operation modes were examined, a simple model is sufficient to assess relevant suspended solids (SS), chemical oxygen demand (COD) and NH4 emissions from RSFs. Two conceptual RSF models with different degrees of complexity were assessed. These models were developed based on evaluation of data from full scale RSF plants and column experiments. Incorporated model processes are ammonium adsorption in the filter layer and degradation during subsequent dry weather period, filtration of SS and particulate COD (XCOD) to a constant background concentration and removal of solute COD (SCOD) by a constant removal rate during filter passage as well as sedimentation of SS and XCOD in the filter overflow. XCOD, SS and ammonium loads as well as ammonium concentration peaks are discharged primarily via RSF overflow not passing through the filter bed. Uncertainties of the integrated simulation of the sewer system and RSF model mainly originate from the model parameters of the hydrologic sewer system model.

Innovative use of lamella clarifiers for central stormwater treatment in separate sewer systems.

PubMed

Weiss, Gebhard

2014-01-01

Lamella settlers have been used in the past few years for the sedimentation of particles in wastewater and stormwater applications. A new and very innovative approach for the treatment of stormwater flows is proposed which extends the portfolio of solutions beyond traditional settling tanks. Surface runoff is stored in a sewer or a basin and finally treated in a small but continuously operated lamella clarifier. The low throughput flow will yield good treatment efficiency at a small footprint. The possibilities of using existing storage volume in a storm sewer, as well as the structural flexibility of the arrangement are decisive benefits. As a large operational advantage, the lamellae may be cleaned mechanically, e.g. by pivoting under water. Finally, the flow and the sludge which will be sent to the downstream treatment plant will be minimized. A new comparative simulation method is proposed in order to assess an equivalent degree of stormwater treatment, either by achieving an equal annual volume of treated stormwater or, more directly, an equal amount of spilled pollutant load. The new solution is compared with a traditional settling tank according to current German design rules. Additionally, a case study from a real installation will be presented.

HANDBOOK: SEWER SYSTEM INFRASTRUCTURE ANALYSIS AND REHABILITATION

EPA Science Inventory

Many of our Nation's sewer systems date back to the 19th Century when brick sewers were common. hese and more recent sewer systems can be expected to fail in time, but because they are placed underground, signs of accelerated deterioration and capacity limitations are not readily...

A support vector regression-firefly algorithm-based model for limiting velocity prediction in sewer pipes.

PubMed

Ebtehaj, Isa; Bonakdari, Hossein

2016-01-01

Sediment transport without deposition is an essential consideration in the optimum design of sewer pipes. In this study, a novel method based on a combination of support vector regression (SVR) and the firefly algorithm (FFA) is proposed to predict the minimum velocity required to avoid sediment settling in pipe channels, which is expressed as the densimetric Froude number (Fr). The efficiency of support vector machine (SVM) models depends on the suitable selection of SVM parameters. In this particular study, FFA is used by determining these SVM parameters. The actual effective parameters on Fr calculation are generally identified by employing dimensional analysis. The different dimensionless variables along with the models are introduced. The best performance is attributed to the model that employs the sediment volumetric concentration (C(V)), ratio of relative median diameter of particles to hydraulic radius (d/R), dimensionless particle number (D(gr)) and overall sediment friction factor (λ(s)) parameters to estimate Fr. The performance of the SVR-FFA model is compared with genetic programming, artificial neural network and existing regression-based equations. The results indicate the superior performance of SVR-FFA (mean absolute percentage error = 2.123%; root mean square error =0.116) compared with other methods.

75 FR 53342 - Notice of Lodging of Proposed Consent Decree Under the Clean Water Act

Federal Register 2010, 2011, 2012, 2013, 2014

2010-08-31

... including raw sewage from the City's sanitary sewer system and its separate storm sewer system, as well as a... remedial measures, including necessary upgrades to its sanitary sewer system and separate storm sewer system, over a period of approximately twelve years and at an estimated cost of approximately $50 million...

Real-time Control of sewer pumps by using ControlNEXT to smooth inflow at Waste Water Treatment Plant Garmerwolde

NASA Astrophysics Data System (ADS)

van Heeringen, Klaas-Jan; van Nooijen, Ronald; Kooij, Kees; Postma, Bokke

2016-04-01

The Garmerwolde waste water treatment plant (WWTP) in the Groningen area of the Netherlands, receives waste water from a large area. That waste water is collected from many sewer systems and transported to the WWTP through pressurized pipes. The supply of waste water to the WWTP is relatively low and very irregular during dry-weather conditions, resulting in a random pattern of flows. This irregularity is the effect of the local control of the pumps, where the pumps are individually operated as an on/off control based on the water levels in the connected sewer system. The influent may change from zero to high values in a few minutes. The treatment processes at the WWTP are negatively influenced by this irregularity, which ends in high costs for energy and use of chemicals. The ControlNEXT central control system is used to control the 5 largest pump stations, such that the total inflow at the WWTP becomes much smoother. This results in a reduction of operational costs of about 10%. The control algorithm determines whether the actual condition is dry or wet, based on real-time radar precipitation images and the rainfall forecast product HiRLAM. All actual data is also collected and validated, like water levels, pump operations and pump availability. This data management is done using Delft-FEWS. If the situation is identified as "wet", the sewer systems are emptied as far as possible to create maximum storage. If the situation is "dry" (and of course there is a dead band between dry and wet), the pumps are operated such that the total inflow into the WWTP is smoothed. This is done with a Greedy algorithm, developed by Delft University of Technology. The algorithm makes a plan for the next 24 hours (as the daily inflow has a typical daily pattern) and generally stores some water volume in the sewer systems during the day to be able to continue operations during the night. The pumps are controlled with a time step of 5 minutes, where ControlNEXT manages the communication of pump operation setpoints to the SCADA system. In case of failing communication, backup procedures are programmed in the PLC of the pump stations. In that case the old on/off operation based on local water levels will be used. The system has been operational since January 2016 and has been monitored since then. In addition to monitoring the positive effect on the inflow at the WWTP, an important issue is the possible sedimentation in the sewer systems. This will be monitored too.

COMBINED-SEWER OVERFLOW CONTROL AND TREATMENT

EPA Science Inventory

Combined-sewer overflow (CSO), along with sanitary-sewer overflow and stormwater are significant contributors of contamination to surface waters. During a rain event, the flow in a combined sewer system may exceed the capacity of the intercepting sewer leading to the wastewater t...

EPA SSOAP Toolbox Application for Condition and Capacity Assessment of Wastewater Collection Systems - Paper

EPA Science Inventory

The nation’s sanitary sewer infrastructure is aging, with some sewers dating back more than 100 years. Nationwide, there are more than 19,500 municipal sanitary-sewer collection systems serving an estimated 150 million people and about 40,000 sanitary sewer overflow (SSO) events ...

EPA SSOAP Toolbox Application for Condition and Capacity Assessment of Wastewater Collection Systems

EPA Science Inventory

The Nation’s sanitary sewer infrastructure is aging, with some sewers dating back over 100 years. Nationwide, there are more than 19,500 municipal sanitary-sewer collection systems serving an estimated 150 million people and about 40,000 sanitary sewer overflow (SSO) events per ...

Tree root intrusion in sewer systems: A review of extent and costs

Treesearch

T.B. Randrup; E.G. McPherson; L.R. Costello

2001-01-01

Interference between trees and sewer systems is likely to occur in old systems and in cracked pipes. Factors that contribute to damage include old pipes with joints, shallow pipes, small-dimension pipes, and fast-growing tree species. Because roots are reported to cause >50% of all sewer blockages, costs associated with root removal from sewers is substantial. In...

Sewer System Management Plan.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Holland, Robert C.

A Sewer System Management Plan (SSMP) is required by the State Water Resources Control Board (SWRCB) Order No. 2006-0003-DWQ Statewide General Waste Discharge Requirements (WDR) for Sanitary Sewer Systems (General Permit). DOE, National Nuclear Security Administration (NNSA), Sandia Field Office has filed a Notice of Intent to be covered under this General Permit. The General Permit requires a proactive approach to reduce the number and frequency of sanitary sewer overflows (SSOs) within the State. SSMPs must include provisions to provide proper and efficient management, operation, and maintenance of sanitary sewer systems and must contain a spill response plan.

PLANNING FOR SSO CONTROL: HENRICO COUNTY, VA - CASE STUDY

EPA Science Inventory

The nation's sanitary-sewer infrastructure is aging with some sewers over 100 years. There are more than 19,500 municipal sanitary-sewer collecton systems nationwide serving 150M people comprising 500,000 sewer miles. About 40,000 sanitary-sewer overflow (SSO) events nationwide y...

Fibre-optic distributed temperature sensing in combined sewer systems.

PubMed

Schilperoort, R P S; Clemens, F H L R

2009-01-01

This paper introduces the application of fibre-optic distributed temperature sensing (DTS) in combined sewer systems. The DTS-technique uses a fibre-optic cable that is inserted into a combined sewer system in combination with a laser instrument that performs measurements and logs the data. The DTS-technique allows monitoring in-sewer temperatures with dense spatial and temporal resolutions. The installation of a fibre-optic cable in a combined sewer system has proven feasible. The use of a single instrument in an easy accessible and safe location that can simultaneously monitor up to several hundreds of monitoring locations makes the DTS set-up easy in use and nearly free of maintenance. Temperature data from a one-week monitoring campaign in an 1,850 m combined sewer system shows the level of detail with which in-sewer processes that affect wastewater temperatures can be studied. Individual discharges from house-connections can be tracked in time and space. With a dedicated cable configuration the confluence of wastewater flows can be observed with a potential to derive the relative contributions of contributary flows to a total flow. Also, the inflow and in-sewer propagation of stormwater can be monitored.

Suspended solids transport: an analysis based on turbidity measurements and event based fully calibrated hydrodynamic models.

PubMed

Langeveld, J G; Veldkamp, R G; Clemens, F

2005-01-01

Modelling suspended solids transport is a key issue for predicting the pollution load discharged by CSOs. Nonetheless, there is still much debate on the main drivers for suspended solids transport and on the modelling approach to be adopted. Current sewer models provide suspended solids transport models. These models, however, rely upon erosion-deposition criteria developed in fluvial environments, therewith oversimplifying the sewer sediment characteristics. Consequently, the performance of these models is poor from a theoretical point of view. To get an improved understanding of the temporal and spatial variations in suspended solids transport, a measuring network was installed in the sewer system of Loenen in conjunction with a hydraulic measuring network from June through December 2001. During the measuring period, 15 storm events rendered high-quality data on both the hydraulics and the turbidity. For each storm event, a hydrodynamic model was calibrated using the Clemens' method. The conclusion of the paper is that modelling of suspended solids transport has been and will be one of the challenges in the field of urban drainage modelling. A direct relation of either shear stress or flow velocity with turbidity could not be found, likely because of the time varying characteristics of the suspended solids.

Sedimentation survey of Lago Lucchetti, Yauco, Puerto Rico, September 2013–May 2014

USGS Publications Warehouse

Gómez-Fragoso, Julieta

2016-08-23

The U.S. Geological Survey conducted a sedimentation survey of Lago Lucchetti, Yauco, Puerto Rico, in 2013–14 in cooperation with the Puerto Rico Aqueduct and Sewer Authority. The survey updated a previous survey, conducted in 2000, and provided accurate information regarding reservoir storage capacity and sedimen­tation rate using bathymetric techniques and a global positioning system coupled with a depth sounder device. The results of the 2013–14 survey indicated a total storage capacity for Lago Lucchetti of 10.21 million cubic meters and a long­-term sedimentation rate loss of 0.16 million cubic meters per year based on the original capacity in 1952. Sediment accumulation was about 10.14 million cubic meters over the life of the reservoir, which represents a storage decrease of about 50 percent of the original capacity in 1952. On the basis of a comparison between the 2013–14 and 2000 surveys, the useful life for Lago Lucchetti is projected to end in 2076.

Advances in Sewer Condition and Capacity Assessment – Development and Applications of EPA SSOAP Toolbox

EPA Science Inventory

In the United States, sanitary sewer infrastructure is aging, with some sewers dating back over 100 years. Nationwide, there are more than 19,500 municipal sanitary-sewer collection systems serving an estimated 150 million people and about 40,000 sanitary sewer overflow (SSO) ev...

U.S. EPA Issues Technical Guides and Computer Tools for Sewer Condition and Capacity Assessment

EPA Science Inventory

The nation's sanitary sewer infrastructure is aging, with some sewers more than100 years old. Nationwide, there are more than 19,500 municipal sanitary-sewer collection systems serving an estimated 150 million people and about 40,000 sanitary sewer overflow (SSO) events per year...

Hydrocarbons and heavy metals in the different sewer deposits in the 'Le Marais' catchment (Paris, France): stocks, distributions and origins.

PubMed

Rocher, Vincent; Azimi, Sam; Moilleron, Régis; Chebbo, Ghassan

2004-05-05

The knowledge of the pollution stored in combined sewers is of prime importance in terms of management of wet weather flow pollution since sewer deposits play a significant role as source of pollution in combined sewer overflows. This work, which focused on the hydrocarbon (aliphatic and aromatic hydrocarbons) and metallic (Fe, Zn, Pb, Cu and Cd) pollution fixed to the different kinds of sewer deposits (gross bed sediment [GBS], organic layer [OL] and biofilm), was performed in order to provide a complete overview of the contaminant storage in the 'Le Marais' combined sewer (Central Paris, France). Firstly, our results have shown that, for all kinds of pollutants, a major part was stored in the GBS (87 to 98%), a lesser part in the OL (2 to 13%) and an insignificant part in the biofilm (<1%). These results demonstrated that the potential contribution of biofilm to wet weather pollution was negligible compared to the OL one. Secondly, the investigation of hydrocarbon fingerprints in each deposit has provided relevant information about contamination origins: (1) aliphatic hydrocarbon distributions were indicative of petroleum input in the GBS and reflected a mixture of biogenic and petroleum inputs in the OL and biofilm, (2) aromatic hydrocarbon distributions suggested an important pyrolytic contamination in all the deposits. Finally, the study of pollutant fingerprints in the different deposits and in the suspended solids going through the collector has shown that: (1) the suspended solids were the major component of OL and biofilm while urban runoff seemed to be the main transport mechanism introducing pollutants in the GBS and (2) the residence times in sewer of OL and biofilm were quite short compared to those for GBS.

78 FR 20316 - Draft Small Municipal Separate Storm Sewer System NPDES General Permit-New Hampshire; Extension...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-04-04

... ENVIRONMENTAL PROTECTION AGENCY [FRL-9799-1] Draft Small Municipal Separate Storm Sewer System NPDES General Permit--New Hampshire; Extension of Comment Period AGENCY: Environmental Protection Agency... draft Small Municipal Separate Storm Sewer System (MS4) National Pollutant Discharge Elimination System...

78 FR 27964 - Draft Small Municipal Separate Storm Sewer System NPDES General Permit-New Hampshire; Extension...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-05-13

... ENVIRONMENTAL PROTECTION AGENCY [FRL-9812-8] Draft Small Municipal Separate Storm Sewer System NPDES General Permit--New Hampshire; Extension of Comment Period AGENCY: Environmental Protection Agency... draft Small Municipal Separate Storm Sewer System (MS4) National Pollutant Discharge Elimination System...

COMPUTER TOOLS FOR SANITARY SEWER SYSTEM CAPACITY ANALYSIS AND PLANNING

EPA Science Inventory

Rainfall-derived infiltration and inflow (RDII) into sanitary sewer systems has long been recognized as a major source of operating problems, causing poor performance of many sewer systems. RDII is the main cause of SSOs to customer basements, streets, or nearby streams and can a...

Optimization of the central automatic control of a small Dutch sewer system

NASA Astrophysics Data System (ADS)

Kolechkina, A. G.; Hoes, O. A. C.

2012-04-01

A sewer control system was developed in the context of a subsidized project aiming at improvement of surface water quality by control of sewer systems and surface water systems. The project was coordinated by the local water board, "Waterschap Hollandse Delta". Other participants were Delft University of Technology, Deltares and the municipalities Strijen, Cromstrijen, Westmaas, Oud Beijerland and Piershil. As part of the project there were two pilot implementations where a central automatic controller was coupled to the existing SCADA system. For these two pilots the system is now operational. A Dutch urban area in the western part of the Netherlands is usually part of a polder, which is effectively an artificially drained catchment. The urban area itself is split into small subcatchments that manage runoff in different ways. In all cases a large fraction goes into the natural hydrological cycle, but, depending on the design of the local sewer system, a larger or smaller part finds its way into the sewer system. Proper control of this flow is necessary to control surface water quality and to avoid health risks from flow from the sewer into the streets. At each time step the controller switches pumps to distribute the remaining water in the system at the end of the time step over the different subcatchments. The distribution is created based on expert judgment of the relative vulnerability and subcatchment sewer system water quality. It is implemented in terms curves of total system stored volume versus subcatchment stored volume. We describe the process of the adaptation of a controller to two different sewer systems and the understanding of the artificial part of the catchment we gained during this process. In the process of adaptation the type of sewer system (combined foul water and storm water transport or separate foul water and storm water transport) played a major role.

Evaluating rain gardens as a method to reduce the impact of sewer overflows in sources of drinking water.

PubMed

Autixier, Laurène; Mailhot, Alain; Bolduc, Samuel; Madoux-Humery, Anne-Sophie; Galarneau, Martine; Prévost, Michèle; Dorner, Sarah

2014-11-15

The implications of climate change and changing precipitation patterns need to be investigated to evaluate mitigation measures for source water protection. Potential solutions need first to be evaluated under present climate conditions to determine their utility as climate change adaptation strategies. An urban drainage network receiving both stormwater and wastewater was studied to evaluate potential solutions to reduce the impact of combined sewer overflows (CSOs) in a drinking water source. A detailed hydraulic model was applied to the drainage basin to model the implementation of best management practices at a drainage basin scale. The model was calibrated and validated with field data of CSO flows for seven events from a survey conducted in 2009 and 2010. Rain gardens were evaluated for their reduction of volumes of water entering the drainage network and of CSOs. Scenarios with different levels of implementation were considered and evaluated. Of the total impervious area within the basin directly connected to the sewer system, a maximum of 21% could be alternately directed towards rain gardens. The runoff reductions for the entire catchment ranged from 12.7% to 19.4% depending on the event considered. The maximum discharged volume reduction ranged from 13% to 62% and the maximum peak flow rate reduction ranged from 7% to 56%. Of concern is that in-sewer sediment resuspension is an important process to consider with regard to the efficacy of best management practices aimed at reducing extreme loads and concentrations. Rain gardens were less effective for large events, which are of greater importance for drinking water sources. These practices could increase peak instantaneous loads as a result of greater in-sewer resuspension during large events. Multiple interventions would be required to achieve the objectives of reducing the number, total volumes and peak contaminant loads of overflows upstream of drinking water intakes. Copyright © 2014 Elsevier B.V. All rights reserved.

USEPA CAPSTONE REPORT: CONTROL AND TREATMENT

EPA Science Inventory

Combined-sewer overflows (CSOs), sanitary-sewer overflows and stormwater (SW) are significant contributors of contamination to surface waters. During a rain event, the flow in a combined sewer system may exceed the capacity of the intercepting sewer leading to the wastewater trea...

Factors that influence properties of FOG deposits and their formation in sewer collection systems.

PubMed

Iasmin, Mahbuba; Dean, Lisa O; Lappi, Simon E; Ducoste, Joel J

2014-02-01

Understanding the formation of Fat, Oil, and Grease (FOG) deposits in sewer systems is critical to the sustainability of sewer collection systems since they have been implicated in causing sewerage blockages that leads to sanitary sewer overflows (SSOs). Recently, FOG deposits in sewer systems displayed strong similarities with calcium-based fatty acid salts as a result of a saponification reaction. The objective of this study was to quantify the factors that may affect the formation of FOG deposits and their chemical and rheological properties. These factors included the types of fats used in FSEs, environmental conditions (i.e. pH and temperature), and the source of calcium in sewer systems. The results of this study showed that calcium content in the calcium based salts seemed to depend on the solubility limit of the calcium source and influenced by pH and temperature conditions. The fatty acid profile of the calcium-based fatty acid salts produced under alkali driven hydrolysis were identical to the profile of the fat source and did not match the profile of field FOG deposits, which displayed a high fraction of palmitic, a long chain saturated fatty acid. It is hypothesized that selective microbial metabolism of fats and/or biologically induced hydrogenation may contribute to the FOG deposit makeup in sewer system. Therefore, selective removal of palmitic in pretreatment processes may be necessary prior to the discharge of FSE wastes into the sewer collection system. Copyright © 2013 Elsevier Ltd. All rights reserved.

Quantification of sewer system infiltration using delta(18)O hydrograph separation.

PubMed

Prigiobbe, V; Giulianelli, M

2009-01-01

The infiltration of parasitical water into two sewer systems in Rome (Italy) was quantified during a dry weather period. Infiltration was estimated using the hydrograph separation method with two water components and delta(18)O as a conservative tracer. The two water components were groundwater, the possible source of parasitical water within the sewer, and drinking water discharged into the sewer system. This method was applied at an urban catchment scale in order to test the effective water-tightness of two different sewer networks. The sampling strategy was based on an uncertainty analysis and the errors have been propagated using Monte Carlo random sampling. Our field applications showed that the method can be applied easily and quickly, but the error in the estimated infiltration rate can be up to 20%. The estimated infiltration into the recent sewer in Torraccia is 14% and can be considered negligible given the precision of the method, while the old sewer in Infernetto has an estimated infiltration of 50%.

Research note: Mapping spatial patterns in sewer age, material, and proximity to surface waterways to infer sewer leakage hotspots

USGS Publications Warehouse

Hopkins, Kristina G.; Bain, Daniel J.

2018-01-01

Identifying areas where deteriorating sewer infrastructure is in close proximity to surface waterways is needed to map likely connections between sewers and streams. We present a method to estimate sewer installation year and deterioration status using historical maps of the sewer network, parcel-scale property assessment data, and pipe material. Areas where streams were likely buried into the sewer system were mapped by intersecting the historical stream network derived from a 10-m resolution digital elevation model with sewer pipe locations. Potential sewer leakage hotspots were mapped by identifying where aging sewer pipes are in close proximity (50-m) to surface waterways. Results from Pittsburgh, Pennsylvania (USA), indicated 41% of the historical stream length was lost or buried and the potential interface between sewers and streams is great. The co-location of aging sewer infrastructure (>75 years old) near stream channels suggests that 42% of existing streams are located in areas with a high potential for sewer leakage if sewer infrastructure fails. Mapping the sewer-stream interface provides an approach to better understand areas were failing sewers may contribute a disproportional amount of nutrients and other pathogens to surface waterways.

SANITARY SEWER OVERFLOW ANALYSIS AND PLANNING (SSOAP) TOOLBOX

EPA Science Inventory

Description: The Nation's sanitary-sewer infrastructure is aging, with some sewers dating back over 100 years. Nationwide, there are more than 19,500 municipal sanitary-sewer collection systems serving an estimated 150 million people and about 40,000 SSO events per year. Becau...

EPA SSOAP Toolbox – Evolution and Applications

EPA Science Inventory

The nation’s sanitary sewer infrastructure is aging, with some sewers dating back more than 100 years. Nationwide, there are more than 19,500 municipal sanitary-sewer collection systems serving an estimated 150 million people and about 40,000 sanitary sewer overflow (SSO) ...

Measuring Flow Reductions in a Combined Sewer System using Green Infrastructure - abstract

EPA Science Inventory

In 2009, the Louisville and Jefferson County Metropolitan Sewer District (MSD) submitted an Integrated Overflow Abatement Plan (IOAP) addressing combined sewer overflows (CSOs) and sanitary sewer overflows. Many of the solutions involve gray infrastructure, such as large, end-of...

75 FR 5788 - Notice of Availability of Draft National Pollutant Discharge Elimination System (NPDES) General...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-02-04

... Discharge Elimination System (NPDES) General Permits for Small Municipal Separate Storm Sewer Systems (MS4... at 40 CFR 122.26(b)(16) define a small municipal separate storm sewer system as ``* * * all separate storm sewers that are: (1) Owned or operated by the United States, a State, city, town, borough, county...

RTC simulations on large branched sewer systems with SmaRTControl.

PubMed

de Korte, Kees; van Beest, Dick; van der Plaat, Marcel; de Graaf, Erno; Schaart, Niels

2009-01-01

In The Netherlands many large branched sewer systems exist. RTC can improve the performance of these systems. The objective of the universal algorithm of SmaRTControl is to improve the performance of the sewer system and the WWTP. The effect of RTC under rain weather flow conditions is simulated using a hydrological model with 19 drainage districts. The system related inefficiency coefficient (SIC) is introduced for assessment of the performance of sewer systems. The performance can be improved by RTC in combination with increased pumping capacities in the drainage districts, but without increasing the flow to the WWTP. Under dry weather flow conditions the flow to the WWTP can be equalized by storage of wastewater in the sewer system. It is concluded that SmaRTControl can improve the performance, that simulations are necessary and that SIC is an excellent parameter for assessment of the performance.

Sanitary Sewer Overflow Analysis and Planning (SSOAP) Toolbox

EPA Science Inventory

Rainfall-derived infiltration and inflow (RDII) into sanitary sewer systems has long been recognized as a source of operating problems in sewerage systems. RDII is the main cause of sanitary sewer overflows (SSOs) to basements, streets, or nearby receiving waters and can also ...

NPDES Permit for Denver Federal Center Municipal Separate Storm Sewer System in Colorado

EPA Pesticide Factsheets

Denver Federal Center Municipal Separate Storm Sewer System is authorized to discharge from all municipal separate storm sewer outfalls existing as of the effective date of permit CO-R042004 to receiving waters Lakewood, Jefferson County, Colorado.

Comparison of conventional rule based flow control with control processes based on fuzzy logic in a combined sewer system.

PubMed

Klepiszewski, K; Schmitt, T G

2002-01-01

While conventional rule based, real time flow control of sewer systems is in common use, control systems based on fuzzy logic have been used only rarely, but successfully. The intention of this study is to compare a conventional rule based control of a combined sewer system with a fuzzy logic control by using hydrodynamic simulation. The objective of both control strategies is to reduce the combined sewer overflow volume by an optimization of the utilized storage capacities of four combined sewer overflow tanks. The control systems affect the outflow of four combined sewer overflow tanks depending on the water levels inside the structures. Both systems use an identical rule base. The developed control systems are tested and optimized for a single storm event which affects heterogeneously hydraulic load conditions and local discharge. Finally the efficiencies of the two different control systems are compared for two more storm events. The results indicate that the conventional rule based control and the fuzzy control similarly reach the objective of the control strategy. In spite of the higher expense to design the fuzzy control system its use provides no advantages in this case.

Evaluation of the Effectiveness of Five Odor Reducing Agents for Sewer System Odors Using an On-Line Total Reduced Sulfur Analyzer

PubMed Central

Choi, Il; Lee, Hyunjoo; Shin, Joungdu; Kim, Hyunook

2012-01-01

Sewer odors have been a concern to citizens of the Metropolitan Seoul region, which has installed combined sewer systems (CSSs) in 86% of its area. Although a variety of odorants are released from sewers, volatile sulfur compounds (VSCs) have been recognized as major ones. A number of technologies have been proposed to monitor or control odors from sewers. One of the most popular strategies adopted for the control of sewage odor is by applying a commercial odor-reducing agent into the sewer. In this study, the effectiveness of five different commercial odor-reducing agents (i.e., an odor masking agent, an alkaline solution, two microbial agents, and a chemical oxidant) was evaluated by continuously monitoring VSCs released from the sewer with an on-line total reduced sulfur (TRS) analyzer before and after each agent was sprayed into CSSs at five different locations of the city. In short, when the effectiveness of odor treatment was tested in the sewer system using five commercial odor reducing treatments, only the chemical oxidant was good enough to reduce the odor in terms of TRS levels measured before and after the application (p < 0.01). PMID:23223148

PLANNING FOR SSO CONTROL: HENRICO COUNTY, VA - CASE STUDY

EPA Science Inventory

The Nation's sanitary-sewer infrastructure is aging with some sewers dating back over 100 years. There are more than 19,500 municipal sanitary-sewer collection systems nationwide serving an estimated 150M people and comprising about 500,000 sewer miles. It is estimated that there...

COMPUTER MODEL ANALYSIS FOR CONTROL PLANNING OF SANITARY-SEWER OVERFLOWS

EPA Science Inventory

The Nation's sanitary-sewer infrastructure is aging with some sewers dating back over 100 years. There are more than 19,500 municipal sanitary-sewer collection systems nationwide serving an estimated 150 million people and comprising about 800,000 km (500,000 mi) of municipally ...

Review of Sewer Design Criteria and RDII Prediction Methods

EPA Science Inventory

Rainfall-derived Infiltration and Inflow (RDII) into sanitary sewer systems has long been recognized as a source of operating problems in sewerage systems. RDII is the main cause of sanitary sewer overflows (SSOs) to basements, streets, or nearby streams and can also cause serio...

75 FR 67960 - Notice of Availability of Draft National Pollutant Discharge Elimination System (NPDES) General...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-11-04

... Discharge Elimination System (NPDES) General Permits for Small Municipal Separate Storm Sewer Systems (MS4... requirements of the CWA. The regulations at 40 CFR 122.26(b)(16) define a small municipal separate storm sewer system as ``* * * all separate storm sewers that are: (1) Owned or operated by the United States, a State...

Spatial Distribution of Triclosan in Sediments and Water of an Urbanized Estuarine Embayment

EPA Science Inventory

Triclosan (TCS) is a broad spectrum anti-microbial compound found in many consumer and personal care products. TCS enters water bodies primarily through wastewater treatment plant (WWTP) effluent and may also be introduced by combined sewer overflows or surface water runoff. TC...

40 CFR 261.3 - Definition of hazardous waste.

Code of Federal Regulations, 2014 CFR

2014-07-01

... discharged to the refinery oil recovery sewer before primary oil/water/solids separation—heat exchanger bundle cleaning sludge from the petroleum refining industry (EPA Hazardous Waste No. K050), crude oil... oil tank sediment and/or in-line filter/separation solids from petroleum refining operations (EPA...

40 CFR 261.3 - Definition of hazardous waste.

Code of Federal Regulations, 2012 CFR

2012-07-01

... discharged to the refinery oil recovery sewer before primary oil/water/solids separation—heat exchanger bundle cleaning sludge from the petroleum refining industry (EPA Hazardous Waste No. K050), crude oil... oil tank sediment and/or in-line filter/separation solids from petroleum refining operations (EPA...

40 CFR 261.3 - Definition of hazardous waste.

Code of Federal Regulations, 2013 CFR

2013-07-01

... discharged to the refinery oil recovery sewer before primary oil/water/solids separation—heat exchanger bundle cleaning sludge from the petroleum refining industry (EPA Hazardous Waste No. K050), crude oil... oil tank sediment and/or in-line filter/separation solids from petroleum refining operations (EPA...

DEVELOPMENT OF SANITARY SEWER OVERFLOW ANALYSIS AND PLANNING (SSOAP) TOOLBOX

EPA Science Inventory

Rainfall Derived Infiltration and Inflow (RDII) into sanitary sewer systems has long been recognized as a source of operating problems in sewerage systems. RDII is the main cause of sanitary sewer overflows (SSOs) to basements, streets, or nearby streams. RDII can also cause se...

SSOAP - A TOOLBOX FOR SANITARY SEWER OVERFLOW ANALYSIS AND PLANNING

EPA Science Inventory

Rainfall Derived Infiltration and Inflow (RDII) into sanitary sewer systems has long been recognized as a source of operating problems in sewerage systems. RDII is the main cause of sanitary sewer overflows (SSOs) to basements, streets, or nearby streams and can also cause serio...

SSOAP - A TOOLBOX FOR SANITARY SEWER OVERFLOW ANALYSIS AND PLANNING

EPA Science Inventory

Rainfall Derived Infiltration and Inflow (RDII) into sanitary sewer systems has long been recognized as a source of operating problems in sewerage systems. RDII is the main cause of sanitary sewer overflows (SSOs) to basements, streets, or nearby streams and can also cause seriou...

Association between Gastrointestinal Illness and Precipitation in Areas Impacted by Combined Sewer Systems: Utilizing a Distributed Lag Model

EPA Science Inventory

Combined sewer systems collect rainwater runoff, sewage, and industrial wastewater for transit to treatment facilities. With heavy precipitation, volumes can exceed capacity of treatment facilities, and wastewater discharges directly to receiving waters. These combined sewer over...

Groundwater infiltration, surface water inflow and sewerage exfiltration considering hydrodynamic conditions in sewer systems.

PubMed

Karpf, Christian; Hoeft, Stefan; Scheffer, Claudia; Fuchs, Lothar; Krebs, Peter

2011-01-01

Sewer systems are closely interlinked with groundwater and surface water. Due to leaks and regular openings in the sewer system (e.g. combined sewer overflow structures with sometimes reverse pressure conditions), groundwater infiltration and surface water inflow as well as exfiltration of sewage take place and cannot be avoided. In the paper a new hydrodynamic sewer network modelling approach will be presented, which includes--besides precipitation--hydrographs of groundwater and surface water as essential boundary conditions. The concept of the modelling approach and the models to describe the infiltration, inflow and exfiltration fluxes are described. The model application to the sewerage system of the City of Dresden during a flood event with complex conditions shows that the processes of infiltration, exfiltration and surface water inflows can be described with a higher reliability and accuracy, showing that surface water inflow causes a pronounced system reaction. Further, according to the simulation results, a high sensitivity of exfiltration rates on the in-sewer water levels and a relatively low influence of the dynamic conditions on the infiltration rates were found.

Factors affecting economies of scale in combined sewer systems.

PubMed

Maurer, Max; Wolfram, Martin; Anja, Herlyn

2010-01-01

A generic model is introduced that represents the combined sewer infrastructure of a settlement quantitatively. A catchment area module first calculates the length and size distribution of the required sewer pipes on the basis of rain patterns, housing densities and area size. These results are fed into the sewer-cost module in order to estimate the combined sewer costs of the entire catchment area. A detailed analysis of the relevant input parameters for Swiss settlements is used to identify the influence of size on costs. The simulation results confirm that an economy of scale exists for combined sewer systems. This is the result of two main opposing cost factors: (i) increased construction costs for larger sewer systems due to larger pipes and increased rain runoff in larger settlements, and (ii) lower costs due to higher population and building densities in larger towns. In Switzerland, the more or less organically grown settlement structures and limited land availability emphasise the second factor to show an apparent economy of scale. This modelling approach proved to be a powerful tool for understanding the underlying factors affecting the cost structure for water infrastructures.

Incorporation of organic tritium (3H) by marine organisms and sediment in the severn estuary/Bristol channel (UK).

PubMed

McCubbin, D; Leonard, K S; Bailey, T A; Williams, J; Tossell, P

2001-10-01

Discharges of tritium (3H) into the Severn estuary/Bristol Channel (UK) arise from the authorized release of wastes from nuclear power plants at Hinkley Point and Berkley/Oldbury and from the Nycomed-Amersham radiochemical plant, via the sewer system, at Cardiff. The wastes from the nuclear power plants probably consist almost entirely of 3H2O, whereas those from the radiochemical plant also include uncharacterized 3H labelled organic compounds. The total 3H concentrations in demersal fish and other benthic organisms in the vicinity of the Cardiff Eastern sewer outfall are significantly elevated compared to those observed around other UK nuclear establishments. Concentrations in filtered seawater were approximately 10 Bq kg(-1) whilst levels in surface sediment, seaweed (Fucus vesiculosis) and mussels (Mytilus edulis)/flounder (Platichthys flesus) were in the order of 6 x 10(2), 2 x 10(3), and 10(5) Bq kg(-1) (dry weight), respectively. Almost all the 3H found in sediment and biota were organically bound tritium (OBT). The high concentration in these materials, relative to that in seawater, is due to the presence of bioavailable organic 3H labelled compounds in the radiochemical waste. It is suggested that bioaccumulation of 3H by benthic organisms and demersal fish occurs primarily via a pathway of physico-chemical sorption/bacterial transformation of dissolved 3H labelled organic compounds into particulate organic matter, and subsequent transfer up a web of sediment dwelling microbes and meiofauna. Variations in 3H accumulation between individual organisms have been interpreted in terms of their different feeding behaviour. Relatively low concentrations were observed in the herbivorous winkle (Littorina littorea) and the pelagic Sprat (Spratus spratus) compared with other benthic organisms and demersal fish. The elevated 3H concentrations in seafood, due to bioaccumulation of OBT, have low radiological significance even for the local critical group of seafood consumers.

A TOOLBOX FOR SANITARY SEWER OVERFLOW ANALYSIS AND PLANNING (SSOAP) AND APPLICATIONS

EPA Science Inventory

Rainfall Derived Infiltration and Inflow (RDII) into sanitary sewer systems has long been recognized as a source of operating problems in sewerage systems. RDII is the main cause of sanitary sewer overflows (SSOs) to basements, streets, or nearby streams and can also cause seriou...

Separate and combined sewer systems: a long-term modelling approach.

PubMed

Mannina, Giorgio; Viviani, Gaspare

2009-01-01

Sewer systems convey mostly dry weather flow, coming from domestic and industrial sanitary sewage as well as infiltration flow, and stormwater due to meteoric precipitations. Traditionally, in urban drainage two types of sewer systems are adopted: separate and combined sewers. The former convey dry and wet weather flow separately into two different networks, while the latter convey dry and wet weather flow together. Which is the best solution in terms of cost-benefit analysis still remains a controversial subject. The present study was aimed at comparing the pollution loads discharged to receiving bodies by Wastewater Treatment Plant (WWTP) and Combined Sewer Overflow (CSO) for different kinds of sewer systems (combined and separate). To accomplish this objective, a comparison between the two systems was carried out using results from simulations of catchments characterised by different dimensions, population densities and water supply rate. The analysis was based on a parsimonious mathematical model able to simulate the sewer system as well as the WWTP during both dry and wet weather. The rain series employed for the simulations was six years long. Several pollutants, both dissolved and particulate, were modelled. The results confirmed the uncertainties in the choice of one system versus the other, emphasising the concept that case-by-case solutions have to be undertaken. Further, the compared systems showed different responses in terms of effectiveness in reducing the discharged mass to the RWB in relation to the particular pollutant taken into account.

9 CFR 354.34 - Application for inspection service in official plants; approval.

Code of Federal Regulations, 2010 CFR

2010-01-01

... sewer, cesspool, sedimentation tank, etc. (13) Approximate rate of production—indicate hourly rate of..., if so, specify such uses. (10) Hot water facilities—specify facilities such as boilers, storage tanks, mixing valves, etc., and indicate the size and number of boilers and storage tanks. (11) Specify number...

Space-Derived Sewer Monitor

NASA Technical Reports Server (NTRS)

1982-01-01

The QuadraScan Longterm Flow Monitoring System is a second generation sewer monitor developed by American Digital Systems, Inc.'s founder Peter Petroff. Petroff, a former spacecraft instrumentation designer at Marshall Space Flight Center, used expertise based on principles acquired in Apollo and other NASA programs. QuadraScan borrows even more heavily from space technology, for example in its data acquisition and memory system derived from NASA satellites. "One-time" measurements are often plagued with substantial errors due to the flow of groundwater absorbed into the system. These system sizing errors stem from a basic informational deficiency: accurate, reliable data on how much water flows through a sewer system over a long period of time is very difficult to obtain. City officials are turning to "permanent," or long-term sewer monitoring systems. QuadraScan offers many advantages to city officials such as the early warning capability to effectively plan for city growth in order to avoid the crippling economic impact of bans on new sewer connections in effect in many cities today.

Environmental Assessment for the Expansion and Consolidation of the Base Exchange at Joint Base Andrews-Naval Air Facility Washington, Prince George’s County, Maryland

DTIC Science & Technology

2013-08-01

Wildlife Service VOC volatile organic compound WG/CC Wing, Commanding Officer WSSC Washington Suburban Sanitary Commission WWTP waste water...2009a). 3.3 Infrastructure and Utilities 3.3.1 Wastewater Collection and Treatment Sanitary Sewer The sanitary sewer system at JBA was privatized...in February 2006. Terrapin Utility Services, Inc., owns and operates the sanitary sewer system (JBA-NAFW 2013). The majority of the sanitary sewer

A model for methane production in sewers.

PubMed

Chaosakul, Thitirat; Koottatep, Thammarat; Polprasert, Chongrak

2014-09-19

Most sewers in developing countries are combined sewers which receive stormwater and effluent from septic tanks or cesspools of households and buildings. Although the wastewater strength in these sewers is usually lower than those in developed countries, due to improper construction and maintenance, the hydraulic retention time (HRT) could be relatively long and resulting considerable greenhouse gas (GHG) production. This study proposed an empirical model to predict the quantity of methane production in gravity-flow sewers based on relevant parameters such as surface area to volume ratio (A/V) of sewer, hydraulic retention time (HRT) and wastewater temperature. The model was developed from field survey data of gravity-flow sewers located in a peri-urban area, central Thailand and validated with field data of a sewer system of the Gold Coast area, Queensland, Australia. Application of this model to improve construction and maintenance of gravity-flow sewers to minimize GHG production and reduce global warming is presented.

Extreme Precipitation and Emergency Room Visits for Gastrointestinal Illness in Areas With and Without Combined Sewer Systems: An Analysis of Massachusetts Data, 2003-2007

EPA Science Inventory

Background: Combined sewer overflows (CSOs) occur in combined sewer systems when sewage and stormwater runoff discharge into waterbodies potentially contaminating water sources. CSOs are often caused by heavy precipitation and are expected to increase with increasing extreme pre...

Effects of pH, Temperature, Dissolved Oxygen, and Flow Rate on Phosphorus Release Processes at the Sediment and Water Interface in Storm Sewer

PubMed Central

Li, Haiyan; Li, Mingyi; Zhang, Xiaoran

2013-01-01

The effects of pH, temperature, dissolved oxygen (DO), and flow rate on the phosphorus (P) release processes at the sediment and water interface in rainwater pipes were investigated. The sampling was conducted in a residential storm sewer of North Li Shi Road in Xi Cheng District of Beijing on August 3, 2011. The release rate of P increased with the increase of pH from 8 to 10. High temperature is favorable for the release of P. The concentration of total phosphorus (TP) in the overlying water increased as the concentration of DO decreased. With the increase of flow rate from 0.7 m s−1 to 1.1 m s−1, the concentration of TP in the overlying water increased and then tends to be stable. Among all the factors examined in the present study, the flow rate is the primary influence factor on P release. The cumulative amount of P release increased with the process of pipeline runoff in the rainfall events with high intensities and shorter durations. Feasible measures such as best management practices and low-impact development can be conducted to control the P release on urban sediments by slowing down the flow rate. PMID:24349823

Green-blue water in the city: quantification of impact of source control versus end-of-pipe solutions on sewer and river floods.

PubMed

De Vleeschauwer, K; Weustenraad, J; Nolf, C; Wolfs, V; De Meulder, B; Shannon, K; Willems, P

2014-01-01

Urbanization and climate change trends put strong pressures on urban water systems. Temporal variations in rainfall, runoff and water availability increase, and need to be compensated for by innovative adaptation strategies. One of these is stormwater retention and infiltration in open and/or green spaces in the city (blue-green water integration). This study evaluated the efficiency of three adaptation strategies for the city of Turnhout in Belgium, namely source control as a result of blue-green water integration, retention basins located downstream of the stormwater sewers, and end-of-pipe solutions based on river flood control reservoirs. The efficiency of these options is quantified by the reduction in sewer and river flood frequencies and volumes, and sewer overflow volumes. This is done by means of long-term simulations (100-year rainfall simulations) using an integrated conceptual sewer-river model calibrated to full hydrodynamic sewer and river models. Results show that combining open, green zones in the city with stormwater retention and infiltration for only 1% of the total city runoff area would lead to a 30 to 50% reduction in sewer flood volumes for return periods in the range 10-100 years. This is due to the additional surface storage and infiltration and consequent reduction in urban runoff. However, the impact of this source control option on downstream river floods is limited. Stormwater retention downstream of the sewer system gives a strong reduction in peak discharges to the receiving river. However due to the difference in response time between the sewer and river systems, this does not lead to a strong reduction in river flood frequency. The paper shows the importance of improving the interface between urban design and water management, and between sewer and river flood management.

Source tracking of leaky sewers: a novel approach combining fecal indicators in water and sediments.

PubMed

Guérineau, Hélène; Dorner, Sarah; Carrière, Annie; McQuaid, Natasha; Sauvé, Sébastien; Aboulfadl, Khadija; Hajj-Mohamad, Mariam; Prévost, Michèle

2014-07-01

In highly urbanized areas, surface water and groundwater are particularly vulnerable to sewer exfiltration. In this study, as an alternative to Microbial Source Tracking (MST) methods, we propose a new method combining microbial and chemical fecal indicators (Escherichia coli (E. coli)) and wastewater micropollutants (WWMPs) analysis both in water and sediment samples and under different meteorological conditions. To illustrate the use of this method, wastewater exfiltration and subsequent infiltration were identified and quantified by a three-year field study in an urban canal. The gradients of concentrations observed suggest that several sources of fecal contamination of varying intensity may be present along the canal, including feces from resident animal populations, contaminated surface run-off along the banks and under bridge crossings, release from contaminated banks, entrainment of contaminated sediments, and most importantly sewage exfiltration. Calculated exfiltration-infiltration volumes varied between 0.6 and 15.7 m(3)/d per kilometer during dry weather, and between 1.1 and 19.5 m(3)/d per kilometer during wet weather. WWMPs were mainly diluted and degraded below detection limits in water. E. coli remains the best exfiltration indicator given a large volume of dilution and a high abundance in the wastewater source. WWMPs are effective for detecting cumulated contamination in sediments from a small volume source and are particularly important because E. coli on its own does not allow source tracking. Copyright © 2014 Elsevier Ltd. All rights reserved.

Rotating optical geometry sensor for inner pipe-surface reconstruction

NASA Astrophysics Data System (ADS)

Ritter, Moritz; Frey, Christan W.

2010-01-01

The inspection of sewer or fresh water pipes is usually carried out by a remotely controlled inspection vehicle equipped with a high resolution camera and a lightning system. This operator-oriented approach based on offline analysis of the recorded images is highly subjective and prone to errors. Beside the subjective classification of pipe defects through the operator standard closed circuit television (CCTV) technology is not suitable for detecting geometrical deformations resulting from e.g. structural mechanical weakness of the pipe, corrosion of e.g. cast-iron material or sedimentations. At Fraunhofer Institute of Optronics, System Technologies and Image Exploitation (IOSB) in Karlsruhe, Germany, a new Rotating Optical Geometry Sensor (ROGS) for pipe inspection has been developed which is capable of measuring the inner pipe geometry very precisely over the whole pipe length. This paper describes the developed ROGS system and the online adaption strategy for choosing the optimal system parameters. These parameters are the rotation and traveling speed dependent from the pipe diameter. Furthermore, a practicable calibration methodology is presented which guarantees an identification of the several internal sensor parameters. ROGS has been integrated in two different systems: A rod based system for small fresh water pipes and a standard inspection vehicle based system for large sewer Pipes. These systems have been successfully applied to different pipe systems. With this measurement method the geometric information can be used efficiently for an objective repeatable quality evaluation. Results and experiences in the area of fresh water pipe inspection will be presented.

A generic methodology for the optimisation of sewer systems using stochastic programming and self-optimizing control.

PubMed

Mauricio-Iglesias, Miguel; Montero-Castro, Ignacio; Mollerup, Ane L; Sin, Gürkan

2015-05-15

The design of sewer system control is a complex task given the large size of the sewer networks, the transient dynamics of the water flow and the stochastic nature of rainfall. This contribution presents a generic methodology for the design of a self-optimising controller in sewer systems. Such controller is aimed at keeping the system close to the optimal performance, thanks to an optimal selection of controlled variables. The definition of an optimal performance was carried out by a two-stage optimisation (stochastic and deterministic) to take into account both the overflow during the current rain event as well as the expected overflow given the probability of a future rain event. The methodology is successfully applied to design an optimising control strategy for a subcatchment area in Copenhagen. The results are promising and expected to contribute to the advance of the operation and control problem of sewer systems. Copyright © 2015 Elsevier Ltd. All rights reserved.

Understanding the spatial formation and accumulation of fats, oils and grease deposits in the sewer collection system.

PubMed

Dominic, Christopher Cyril Sandeep; Szakasits, Megan; Dean, Lisa O; Ducoste, Joel J

2013-01-01

Sanitary sewer overflows are caused by the accumulation of insoluble calcium salts of fatty acids, which are formed by the reaction between fats, oils and grease (FOG) and calcium found in wastewaters. Different sewer structural configurations (i.e., manholes, pipes, wet wells), which vary spatially, along with other obstructions (roots intrusion) and pipe deformations (pipe sags), may influence the detrimental buildup of FOG deposits. The purpose of this study was to quantify the spatial variation in FOG deposit formation and accumulation in a pilot-scale sewer collection system. The pilot system contained straight pipes, manholes, roots intrusion, and a pipe sag. Calcium and oil were injected into the system and operated at alkaline (pH = 10) and neutral (pH = 7) pH conditions. Results showed that solid accumulations were slightly higher at neutral pH. Fourier transform infrared (FTIR) analysis on the solids samples confirmed that the solids were indeed calcium-based fatty acid salts. However, the fatty acid profiles of the solids deviated from the profile found from FOG deposits in sewer systems, which were primarily saturated fatty acids. These results confirm the work done previously by researchers and suggest an alternative fate of unsaturated fatty acids that does not lead to their incorporation in FOG deposits in full-scale sewer systems.

Spatial Variability of Factors Influencing the Distribution of Triclosan in Sediments and Water of an Urbanized Estuarine Embayment

EPA Science Inventory

Triclosan (TCS) is a broad spectrum anti-microbial compound added to many consumer and personal care products. TCS enters water bodies primarily through wastewater treatment plant (WWTP) effluent and may be introduced by combined sewer overflows or surface water runoff. In estu...

Storm water runoff-a source of emerging contaminants in urban streams

NASA Astrophysics Data System (ADS)

Xia, K.; Chen, C.; FitzGerald, K.; Badgley, B.

2016-12-01

Emerging contaminants (ECs) that refers to prescription, over-the-counter, veterinary, and illicit drugs in addition to products intended to have primary effects on the human body, such as sunscreens and insect repellants. Historically municipal wastewater treatment effluent has been considered to be the main source of ECs in aquatic environment. However, recent investigations have suggested urban storm water runoff as an important source of ECs in the environment. The objective of this multi-year study was to investigate the occurrence of a wide range of ECs and the special and temporal change of 4-Nonlyphenol (4-NP), an endocrine disruptor, in a stream solely impacted by the storm water runoff from Blacksburg, VA. Urban land cover has doubled during the past 15 years surrounding this. Water and sediment samples were collected periodically along the stream during a 3-year period and analyzed for 4-NP using a gas chromatography/tandem mass spectrometry and for EC screening using an ultra- performance liquid chromatography/tandem mass spectrometry. In addition, human-associated Bacteroides sp. (HF183) was analyzed to explore possible cross contamination between the sewer system and storm water collection system of the city. Fifteen ECs were detected in water samples from various locations along the stream at estimated levels ranging from low ppt to low ppb. The levels of 4-NP in the storm water sediment samples, ranging from 30-1500 µg/kg (d.w.), positively correlated with the levels of Human-associated Bacteroides sp. (HF183) in the storm water. Our study suggested: 1) collective urban activity and leaky urban sewer systems are significant sources of ECs in storm water runoff that are often untreated or with minimum treatment before flowing into urban streams; and 2) sediment transport and re-suspension can further releases accumulated ECs back into stream water during rain events, resulting in occurrence of ECs downstream and possibly in the receiving river. This study demonstrated that urband storm water runoff could be a significant source, in addition to WWTP effluent, contributing to the widespread occurrence of ECs in aquatic environment.

Changes in water quality parameters due to in-sewer processes.

PubMed

Boxall, J; Shepherd, W; Guymer, I; Fox, K

2003-01-01

Combined sewer systems contain a large number of organic and inorganic pollutants from both domestic and industrial sources. These pollutants are often retained within the combined sewer system for significant lengths of time before entering sewage treatment works, or being spilt to a watercourse via a combined sewer overflow (CSO) during storm conditions. Currently little knowledge exists concerning the effects of in sewer processes on pollutants. Understanding of in-sewer processes is important for the effective and efficient design of treatment works and CSO chambers and for impact assessments on receiving waters. A series of studies covering storm and dry weather flow conditions were undertaken with the aim of investigating the nature of in-sewer processes. These studies consisted of marking a body of water with a fluorescent tracer. The tracer was then monitored at a series of downstream sites, and discrete samples collected from the body of water as it progressed through the sewer. The samples were analysed for water quality parameters and these results investigated in tandem with the detailed hydraulic information gained through the tracer studies. The results highlight the hydraulic differences between storm and dry weather conditions such as increased travel times and mixing under storm conditions. The Advection Dispersion Equation (ADE) and Aggregated Dead Zone (ADZ) model parameters have been quantified for the tracer data. The ADE mixing coefficient is shown to increase by an order of magnitude for storm conditions. The ADZ dispersive fraction parameter is shown to be approximately constant with flow. Chemical reactions and decay within the sewer system were found to be consistent with oxygen limitation.

Vacuum Flushing of Sewer Solids

EPA Science Inventory

The vacuum sewer and tank cleaning (flushing) technology removes sewer solids from urban drainage systems, such as storage tanks and pipes. This technology is both effective and inexpensive. In addition, it can be considered a true green technology. It operates under atmospheri...

Hydrologic monitoring for Chicago’s Sustainable Streetscapes Program

USGS Publications Warehouse

Duncker, James J.; Morrow, William S.

2016-04-05

The Chicago Department of Transportation’s Sustainable Streetscapes Program is an innovative program that strives to convert Chicago’s neighborhood commercial areas, riverwalks, and bicycle facilities into active, attractive places for Chicagoans to live, work, and play. The objective of each project is to create flourishing public places while improving the ability of infrastructure to support dense urban living. The U.S. Geological Survey (USGS), in cooperation with the Metropolitan Water Reclamation District of Greater Chicago (MWRDGC), and the Chicago Department of Transportation (CDOT), is monitoring the pre- and postconstruction hydrologic characteristics of an urban corridor on the south side of Chicago that is being renovated using sustainable streetscapes technology.The CDOT Sustainable Streetscapes Program utilizes urban stormwater best-management practices (BMPs) to reduce the storm runoff to the local combined sewer system. The urban stormwater BMPs include permeable pavement, bioswales, infiltration basins, and planters. The urban stormwater BMPs are designed to capture the first flush of storm runoff through features that enhance the infiltration of stormwater runoff to shallow groundwater.The hydrology of the Sustainable Streetscapes Program area is being monitored to evaluate the impacts and effectiveness of the urban stormwater BMP’s. Continuous monitoring of rainfall, sewer flows, stormwater runoff, soil moisture, and groundwater levels will give engineers and scientists measured data to define baseline pre- and postconstruction conditions for the evaluation of the BMPs.Three tipping-bucket rain gages are located along the project corridor. The data provide information on the intensity and volume of rainfall. Rainfall can be highly variable even over a small area like the project corridor.Continuous recording meters are located at specific locations in the combined sewers to record water level and flow during both dry weather (mostly sanitary flow) and wet weather conditions (stormwater runoff in addition to the sanitary flow). Sanitary flow is the largest source of flow in the combined sewers during dry weather, and stormwater runoff and sanitary flow combine during wet weather. The sewer flow data allow engineers and scientists to calculate total runoff volume for selected storm events.Wells are located within the project corridor to record water levels and help determine the direction of movement of groundwater in response to rainfall and snowmelt. In urban settings with aging sewer systems, groundwater can seep into the sewers or combined sewage can seep from the sewers into the local groundwater system. The groundwater data are also important in evaluating the overall impacts of increased infiltration resulting from BMPs.Data from wells show the relative water levels of shallow groundwater, water levels in the combined sewer system, and nearby surface-water channels within the project corridor. In some aging urban sewer systems, the local combined sewer system lies below the water table and receives substantial amounts of groundwater inflow, which can significantly reduce the amount of additional water the sewer system can accept.The bioswale along the south side of West Cermak Road near South Throop Street functions to infiltrate stormwater runoff from the road. Stormwater on the road surface initially drains to the curb and then flows along the curb until it reaches a curb cut-out. Materials within the bioswale allow stormwater to infiltrate and reduce the load to the combined sewer.A common feature in urban areas are curbside catch basins that collect stormwater runoff from paved streets. Stormwater drains first to the curb and then flows along the curb to the catch basin. Lateral sewer pipe connects the catch basin to the combined sewer beneath the street. The use of permeable pavers along the curbs in the project study reach let stormwater infiltrate before it reaches the curb, thus reducing the amount of stormwater draining to the combined sewers.Water-level data from catch basins in the project study area show the effects of permeable pavers in reducing the stormwater drainage to the combined sewers.

The hydraulic capacity of deteriorating sewer systems.

PubMed

Pollert, J; Ugarelli, R; Saegrov, S; Schilling, W; Di Federico, V

2005-01-01

Sewer and wastewater systems suffer from insufficient capacity, construction flaws and pipe deterioration. Consequences are structural failures, local floods, surface erosion and pollution of receiving waters bodies. European cities spend in the order of five billion Euro per year for wastewater network rehabilitation. This amount is estimated to increase due to network ageing. The project CARE-S (Computer Aided RE-habilitation of Sewer Networks) deals with sewer and storm water networks. The final project goal is to develop integrated software, which provides the most cost-efficient system of maintenance, repair and rehabilitation of sewer networks. Decisions on investments in rehabilitation often have to be made with uncertain information about the structural condition and the hydraulic performance of a sewer system. Because of this, decision-making involves considerable risks. This paper presents the results of research focused on the study of hydraulic effects caused by failures due to temporal decline of sewer systems. Hydraulic simulations are usually carried out by running commercial models that apply, as input, default values of parameters that strongly influence results. Using CCTV inspections information as dataset to catalogue principal types of failures affecting pipes, a 3D model was used to evaluate their hydraulic consequences. The translation of failures effects in parameters values producing the same hydraulic conditions caused by failures was carried out through the comparison of laboratory experiences and 3D simulations results. Those parameters could be the input of 1D commercial models instead of the default values commonly inserted.

Quantification of groundwater infiltration and surface water inflows in urban sewer networks based on a multiple model approach.

PubMed

Karpf, Christian; Krebs, Peter

2011-05-01

The management of sewer systems requires information about discharge and variability of typical wastewater sources in urban catchments. Especially the infiltration of groundwater and the inflow of surface water (I/I) are important for making decisions about the rehabilitation and operation of sewer networks. This paper presents a methodology to identify I/I and estimate its quantity. For each flow fraction in sewer networks, an individual model approach is formulated whose parameters are optimised by the method of least squares. This method was applied to estimate the contributions to the wastewater flow in the sewer system of the City of Dresden (Germany), where data availability is good. Absolute flows of I/I and their temporal variations are estimated. Further information on the characteristics of infiltration is gained by clustering and grouping sewer pipes according to the attributes construction year and groundwater influence and relating these resulting classes to infiltration behaviour. Further, it is shown that condition classes based on CCTV-data can be used to estimate the infiltration potential of sewer pipes. Copyright © 2011 Elsevier Ltd. All rights reserved.

Vacuum Flushing of Sewer Solids (Slides)

EPA Science Inventory

The vacuum sewer and tank cleaning (flushing) technology removes sewer solids from urban drainage systems, such as storage tanks and pipes. This technology is both effective and inexpensive. In addition, it can be considered a true green technology. It operates under atmospheri...

SANITARY-SEWER OVERFLOW CONTROL STRATEGY

EPA Science Inventory

This paper presents a strategy for the abatement of pollution from storm-generated sanitary-sewer overflows (SSO). Because of the great lengths of sanitary-sewer systems and their associated vast number of house-service laterals or building connections, it is often less expensive...

A dynamic ventilation model for gravity sewer networks.

PubMed

Wang, Y C; Nobi, N; Nguyen, T; Vorreiter, L

2012-01-01

To implement any effective odour and corrosion control technology in the sewer network, it is imperative that the airflow through gravity sewer airspaces be quantified. This paper presents a full dynamic airflow model for gravity sewer systems. The model, which is developed using the finite element method, is a compressible air transport model. The model has been applied to the North Head Sewerage Ocean Outfall System (NSOOS) and calibrated using the air pressure and airflow data collected during October 2008. Although the calibration is focused on forced ventilation, the model can be applied to natural ventilation as well.

SSOAP - A USEPA Toolbox for Sanitary Sewer Overflow Analysis and Control Planning - Presentation

EPA Science Inventory

The United States Environmental Protection Agency (USEPA) has identified a need to use proven methodologies to develop computer tools that help communities properly characterize rainfall-derived infiltration and inflow (RDII) into sanitary sewer systems and develop sanitary sewer...

CONTROL STRATEGY FOR STORM-GENERATED SANITARY-SEWER OVERFLOWS

EPA Science Inventory

This paper presents a strategy for the abatement of pollution from storm-generated sanitary-sewer overflows (SSO). Because of the great lengths of sanitary sewer systems, it is often less expensive to use alterantives to sewerline rehabilitation for infiltration/inflow (I/I) and ...

CONTROL STRATEGY FOR STORM-GENERATED SANITARY-SEWER OVERFLOWS

EPA Science Inventory

This paper presents a strategy for the abatement of pollution from storm-generated sanitary-sewer overflows (SSO). Because of the great lengths of sanitary-sewer systems and their associated vast number of house-service laterals or building connections, it is often less expensiv...

Control Strategy for Storm-Generated Sanitary Sewer Overflows

EPA Science Inventory

This presentation covers a strategy for the abatement of pollution from sanitary-sewer overflows (SSO). Because of the great lengths of sanitary sewer systems, it is often less expensive to use alternatives to sewerline rehabilitation for infiltration/inflow (I/I) and associated ...

Smart Water Conservation System for Irrigated Landscape

DTIC Science & Technology

2016-05-01

purple pipe indicating reuse water) and properly labeled “not for human consumption”; • Do not connect rainwater overflow discharge to sanitary sewer...Report Smart Water Conservation System 75 May 2016 Condensate Capture If redirecting condensate from sanitary sewer, ensure sewer gases are managed...the spring/early summer to determine optimum irrigation safety factor. Irrigate at night or early morning. Set soak and cycle for clay soils. ET

Vision-based system for the control and measurement of wastewater flow rate in sewer systems.

PubMed

Nguyen, L S; Schaeli, B; Sage, D; Kayal, S; Jeanbourquin, D; Barry, D A; Rossi, L

2009-01-01

Combined sewer overflows and stormwater discharges represent an important source of contamination to the environment. However, the harsh environment inside sewers and particular hydraulic conditions during rain events reduce the reliability of traditional flow measurement probes. In the following, we present and evaluate an in situ system for the monitoring of water flow in sewers based on video images. This paper focuses on the measurement of the water level based on image-processing techniques. The developed image-based water level algorithms identify the wall/water interface from sewer images and measure its position with respect to real world coordinates. A web-based user interface and a 3-tier system architecture enable the remote configuration of the cameras and the image-processing algorithms. Images acquired and processed by our system were found to reliably measure water levels and thereby to provide crucial information leading to better understand particular hydraulic behaviors. In terms of robustness and accuracy, the water level algorithm provided equal or better results compared to traditional water level probes in three different in situ configurations.

Demonstration of Innovative Sewer System Inspection Technology SewerBatt

EPA Science Inventory

The overall objective of this EPA-funded study was to demonstrate innovative a sewer line assessment technology that is designed for rapid deployment using portable equipment. This study focused on demonstration of a technology that is suitable for smaller diameter pipes (less th...

Identification of potential sewer mining locations: a Monte-Carlo based approach.

PubMed

Tsoukalas, I K; Makropoulos, C K; Michas, S N

2017-12-01

Rapid urbanization affecting demand patterns, coupled with potential water shortages due to supply side impacts of climatic changes, has led to the emergence of new technologies for water and wastewater reuse. Sewer mining (SM) is a novel decentralized option that could potentially provide non-potable water for urban uses, including for example the irrigation of urban green spaces, providing a mid-scale solution to effective wastewater reuse. SM is based on extracting wastewater from local sewers and treatment at the point of demand and entails in some cases the return of treatment residuals back to the sewer system. Several challenges are currently in the way of such applications in Europe, including public perception, inadequate regulatory frameworks and engineering issues. In this paper we consider some of these engineering challenges, looking at the sewer network as a system where multiple physical, biological and chemical processes take place. We argue that prior to implementing SM, the dynamics of the sewer system should be investigated in order to identify optimum ways of deploying SM without endangering the reliability of the system. Specifically, both wastewater extraction and sludge return could result in altering the biochemical process of the network, thus unintentionally leading to degradation of the sewer infrastructure. We propose a novel Monte-Carlo based method that takes into account both spatial properties and water demand characteristics of a given area of SM deployment while simultaneously accounting for the variability of sewer network dynamics in order to identify potential locations for SM implementation. The outcomes of this study suggest that the method can provide rational results and useful guidelines for upscale SM technologies at a city level.

Dopant-assisted negative photoionization Ion mobility spectrometry coupled with on-line cooling inlet for real-time monitoring H2S concentration in sewer gas.

PubMed

Peng, Liying; Jiang, Dandan; Wang, Zhenxin; Hua, Lei; Li, Haiyang

2016-06-01

Malodorous hydrogen sulfide (H2S) gas often exists in the sewer system and associates with the problems of releasing the dangerous odor to the atmosphere and causing sewer pipe to be corroded. A simple method is in demand for real-time measuring H2S level in the sewer gas. In this paper, an innovated method based on dopant-assisted negative photoionization ion mobility spectrometry (DANP-IMS) with on-line semiconductor cooling inlet was put forward and successfully applied for the real-time measurement of H2S in sewer gas. The influence of moisture was effectively reduced via an on-line cooling method and a non-equilibrium dilution with drift gas. The limits of quantitation for the H2S in ≥60% relative humidity air could be obtained at ≤79.0ng L(-1) with linear ranges of 129-2064ng L(-1). The H2S concentration in a sewer manhole was successfully determined while its product ions were identified by an ion-mobility time-of-fight mass spectrometry. Finally, the correlation between sewer H2S concentration and the daily routines and habits of residents was investigated through hourly or real-time monitoring the variation of sewer H2S in manholes, indicating the power of this DANP-IMS method in assessing the H2S concentration in sewer system. Copyright © 2016 Elsevier B.V. All rights reserved.

OPTIMIZATION OF COMBINED SEWER OVERFLOW CONTROL SYSTEMS

EPA Science Inventory

The highly variable and intermittent pollutant concentrations and flowrates associated with wet-weather events in combined sewersheds necessitates the use of storage-treatment systems to control pollution.An optimized combined-sewer-overflow (CSO) control system requires a manage...

A new database on urban runoff pollution: comparison of separate and combined sewer systems.

PubMed

Brombach, H; Weiss, G; Fuchs, S

2005-01-01

For a long time people have questioned what the "best" sewer system is for limiting the pollution load released into the receiving waters. In this paper the traditional separate and combined sewer systems are compared using a pollution load balance. The investigation is based on measured concentration data for a range of pollutant parameters in the sewer from the new database "ATV-DVWK Datenpool 2001". The approach also accounted for the wastewater treatment plant outflow which contributes to the total pollutant load considerably. In spite of a number of neglected effects, the results show that the separate system is superior to the combined for some parameters only, such as nutrients, whereas for other parameters, e.g. heavy metals and COD, the combined system yields less total loads. Any uncritical preference of the separate system as a particularly advantageous solution is thus questionable. Individual investigations case by case are recommended.

Storm water management in an urban catchment: effects of source control and real-time management of sewer systems on receiving water quality.

PubMed

Frehmann, T; Nafo, I; Niemann, A; Geiger, W F

2002-01-01

For the examination of the effects of different storm water management strategies in an urban catchment area on receiving water quality, an integrated simulation of the sewer system, wastewater treatment plant and receiving water is carried out. In the sewer system real-time control measures are implemented. As examples of source control measures the reduction of wastewater and the reduction of the amount of impervious surfaces producing storm water discharges are examined. The surface runoff calculation and the simulation of the sewer system and the WWTP are based on a MATLAB/SIMULINK simulation environment. The impact of the measures on the receiving water is simulated using AQUASIM. It can be shown that the examined storm water management measures, especially the source control measures, can reduce the combined sewer overflow volume and the pollutant discharge load considerably. All examined measures also have positive effects on the receiving water quality. Moreover, the reduction of impervious surfaces avoids combined sewer overflow activities, and in consequence prevents pollutants from discharging into the receiving water after small rainfall events. However, the receiving water quality improvement may not be seen as important enough to avoid acute receiving water effects in general.

Sanitary Sewer Systems and Association with Gastrointestinal Illness: A case crossover analysis of Massachusetts Data, 2006-2008

EPA Science Inventory

Sanitary sewer overflows (SSOs) occur when untreated sewage is discharged into water sources before reaching the treatment facility potentially contaminating them with gastrointestinal pathogens. Causes of SSOs include heavy rainfall and rupture/blockage of sewer lines. Few studi...

INNOVATIVE METHODS FOR THE OPTIMIZATION OF GRAVITY STORM SEWER DESIGN

EPA Science Inventory

The purpose of this paper is to describe a new method for optimizing the design of urban storm sewer systems. Previous efforts to optimize gravity sewers have met with limited success because classical optimization methods require that the problem be well behaved, e.g. describ...

Colorado River Sewer System Joint Venture to Upgrade Wastewater System

EPA Pesticide Factsheets

SAN FRANCISCO -Today, the Colorado River Sewer System Joint Venture, located in Parker, Ariz. entered into an agreement with the EPA to upgrade their wastewater treatment system to meet stringent water quality standards. The cost of the upgrade is ap

Sewer Maintenance Manual.

ERIC Educational Resources Information Center

Ontario Ministry of the Environment, Toronto.

Outlined are practices and procedures that should be followed in order to protect and fully realize the benefits of sewer systems and also to maximize service and minimize inconveniences to the public. Written in practical terms, the manual is designed to be of immediate use to municipal employees and others involved in sewer maintenance…

Update on the Status of Sanitary Sewer Overflow Analysis and Planning (SSOAP) Toolbox

EPA Science Inventory

A properly designed, operated and maintained sanitary sewer system is meant to collect and convey all of the sewage that flows into it to a wastewater treatment plant. However, occasional unintentional discharges of raw sewage from municipal sanitary sewers – called sanitary sewe...

Condition Assessment of Wastewater Collection Systems

EPA Science Inventory

Municipal sanitary sewer collection systems play a critical role in protecting public health in our municipalities. They are designed to convey wastewater from their sources to a wastewater treatment plant (WWTP). Collection systems consist of house service laterals, sewers, pu...

Temporal asymmetry in precipitation time series and its influence on flow simulations in combined sewer systems

NASA Astrophysics Data System (ADS)

Müller, Thomas; Schütze, Manfred; Bárdossy, András

2017-09-01

A property of natural processes is temporal irreversibility. However, this property cannot be reflected by most statistics used to describe precipitation time series and, consequently, is not considered in most precipitation models. In this paper, a new statistic, the asymmetry measure, is introduced and applied to precipitation enabling to detect and quantify irreversibility. It is used to analyze two different data sets of Singapore and Germany. The data of both locations show a significant asymmetry for high temporal resolutions. The asymmetry is more pronounced for Singapore where the climate is dominated by convective precipitation events. The impact of irreversibility on applications is analyzed on two different hydrological sewer system models. The results show that the effect of the irreversibility can lead to biases in combined sewer overflow statistics. This bias is in the same order as the effect that can be achieved by real time control of sewer systems. Consequently, wrong conclusion can be drawn if synthetic time series are used for sewer systems if asymmetry is present, but not considered in precipitation modeling.

Status of Civil Judicial Consent Decrees Addressing Combined Sewer Systems (CSOs)

EPA Pesticide Factsheets

Tracking table of civil consent decrees for combined sewer systems (CSOs). This supports the National Enforcement Initiative (NEI) for Keeping Raw Sewage and Contaminated Stormwater Out of Our Nation's Waters.

Coordinated management of combined sewer overflows by means of environmental decision support systems.

PubMed

Murla, Damian; Gutierrez, Oriol; Martinez, Montse; Suñer, David; Malgrat, Pere; Poch, Manel

2016-04-15

During heavy rainfall, the capacity of sewer systems and wastewater treatment plants may be surcharged producing uncontrolled wastewater discharges and a depletion of the environmental quality. Therefore there is a need of advanced management tools to tackle with these complex problems. In this paper an environmental decision support system (EDSS), based on the integration of mathematical modeling and knowledge-based systems, has been developed for the coordinated management of urban wastewater systems (UWS) to control and minimize uncontrolled wastewater spills. Effectiveness of the EDSS has been tested in a specially designed virtual UWS, including two sewers systems, two WWTP and one river subjected to typical Mediterranean rain conditions. Results show that sewer systems, retention tanks and wastewater treatment plants improve their performance under wet weather conditions and that EDSS can be very effective tools to improve the management and prevent the system from possible uncontrolled wastewater discharges. Copyright © 2016 Elsevier B.V. All rights reserved.

U.S. EPA CSO CAPSTONE REPORT: CONTROL SYSTEM OPTIMIZATION

EPA Science Inventory

An optimized combined sewer overflow (CSO) requires a storage treatment system because storm flow in the combined sewer system is intermittent and highly variable in both pollutant concentration and flow rate. Storage and treatment alternatives are strongly influenced by input...

Assessing the efficiency of different CSO positions based on network graph characteristics.

PubMed

Sitzenfrei, R; Urich, C; Möderl, M; Rauch, W

2013-01-01

The technical design of urban drainage systems comprises two major aspects: first, the spatial layout of the sewer system and second, the pipe-sizing process. Usually, engineers determine the spatial layout of the sewer network manually, taking into account physical features and future planning scenarios. Before the pipe-sizing process starts, it is important to determine locations of possible weirs and combined sewer overflows (CSOs) based on, e.g. distance to receiving water bodies or to a wastewater treatment plant and available space for storage units. However, positions of CSOs are also determined by topological characteristics of the sewer networks. In order to better understand the impact of placement choices for CSOs and storage units in new systems, this work aims to determine case unspecific, general rules. Therefore, based on numerous, stochastically generated virtual alpine sewer systems of different sizes it is investigated how choices for placement of CSOs and storage units have an impact on the pipe-sizing process (hence, also on investment costs) and on technical performance (CSO efficiency and flooding). To describe the impact of the topological positions of these elements in the sewer networks, graph characteristics are used. With an evaluation of 2,000 different alpine combined sewer systems, it was found that, as expected, with CSOs at more downstream positions in the network, greater construction costs and better performance regarding CSO efficiency result. At a specific point (i.e. topological network position), no significant difference (further increase) in construction costs can be identified. Contrarily, the flooding efficiency increases with more upstream positions of the CSOs. Therefore, CSO and flooding efficiency are in a trade-off conflict and a compromise is required.

Assessing the Impacts of Pulp Loading from Non-Dispersible Materials on Downstream Sewer Systems (WERF Report INFR1R14)

EPA Science Inventory

Abstract:This study subjected wipes from five different manufacturers to a variety of tests to determine if changes to their physical characteristics occur when introduced into a sewer systemand what effect the shredded material (pulp) has on the downstream sewer. Shredded and no...

Final Environmental Assessment for the Disposal of the Former Lynn Haven Fuel Depot, Tyndall Air Force Base, Florida

DTIC Science & Technology

2015-12-01

groundwater), infrastructure/utilities (i.e., sanitary sewer, potable water, solid waste management, drainage, transportation systems, electricity and...on water resources (i.e., surface water and groundwater), infrastructure/utilities (i.e., sanitary sewer, potable water, solid waste management...3-8 3.3.6.4 Sanitary Sewer

40 CFR 35.925-21 - Storm sewers.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 1 2012-07-01 2012-07-01 false Storm sewers. 35.925-21 Section 35.925... STATE AND LOCAL ASSISTANCE Grants for Construction of Treatment Works-Clean Water Act § 35.925-21 Storm... treatment works for control of pollutant discharges from a separate storm sewer system (as defined in § 35...

40 CFR 35.925-21 - Storm sewers.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 1 2010-07-01 2010-07-01 false Storm sewers. 35.925-21 Section 35.925... STATE AND LOCAL ASSISTANCE Grants for Construction of Treatment Works-Clean Water Act § 35.925-21 Storm... treatment works for control of pollutant discharges from a separate storm sewer system (as defined in § 35...

40 CFR 35.925-21 - Storm sewers.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 1 2014-07-01 2014-07-01 false Storm sewers. 35.925-21 Section 35.925... STATE AND LOCAL ASSISTANCE Grants for Construction of Treatment Works-Clean Water Act § 35.925-21 Storm... treatment works for control of pollutant discharges from a separate storm sewer system (as defined in § 35...

40 CFR 35.925-21 - Storm sewers.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 1 2011-07-01 2011-07-01 false Storm sewers. 35.925-21 Section 35.925... STATE AND LOCAL ASSISTANCE Grants for Construction of Treatment Works-Clean Water Act § 35.925-21 Storm... treatment works for control of pollutant discharges from a separate storm sewer system (as defined in § 35...

40 CFR 35.925-21 - Storm sewers.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 1 2013-07-01 2013-07-01 false Storm sewers. 35.925-21 Section 35.925... STATE AND LOCAL ASSISTANCE Grants for Construction of Treatment Works-Clean Water Act § 35.925-21 Storm... treatment works for control of pollutant discharges from a separate storm sewer system (as defined in § 35...

7. VIEW TO NORTH SHOWING SEWER CONSTRUCTION IN FOREGROUND AND ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

7. VIEW TO NORTH SHOWING SEWER CONSTRUCTION IN FOREGROUND AND BUILDING F IN THE LEFT BACKGROUND. 8X10 black and white gelatin print. United States Coast Guard, Air Station Contract 1247, Sewer System. 1956. - U.S. Coast Guard Air Station San Francisco, 1020 North Access Road, San Francisco, San Francisco County, CA

Disparities in Water and Sewer Services in North Carolina: An Analysis of the Decision-Making Process

PubMed Central

Gibson, Jacqueline MacDonald

2015-01-01

Objectives. We examined the factors that affect access to municipal water and sewer service for unincorporated communities relying on wells and septic tanks. Methods. Using a multisite case study design, we conducted in-depth, semistructured interviews with 25 key informants from 3 unincorporated communities in Hoke, New Hanover, and Transylvania counties, North Carolina, July through September 2013. Interviewees included elected officials, health officials, utility providers, and community members. We coded the interviews in ATLAS.ti to identify common themes. Results. Financing for water and sewer service emerged as the predominant factor that influenced decisions to extend these services. Improved health emerged as a minor factor, suggesting that local officials may not place a high emphasis on the health benefits of extending public water and sewer services. Awareness of failed septic systems in communities can prompt city officials to extend sewer service to these areas; however, failed systems are often underreported. Conclusions. Understanding the health costs and benefits of water and sewer extension and integrating these findings into the local decision-making process may help address disparities in access to municipal services. PMID:26270307

Impact of reduced water consumption on sulfide and methane production in rising main sewers.

PubMed

Sun, Jing; Hu, Shihu; Sharma, Keshab Raj; Bustamante, Heriberto; Yuan, Zhiguo

2015-05-01

Reduced water consumption (RWC), for water conservation purposes, is expected to change the wastewater composition and flow conditions in sewer networks and affect the in-sewer transformation processes. In this study, the impact of reduced water consumption on sulfide and methane production in rising main sewers was investigated. Two lab-scale rising main sewer systems fed with wastewater of different strength and flow rates were operated to mimic sewers under normal and RWC conditions (water consumption reduced by 40%). Sulfide concentration under the RWC condition increased by 0.7-8.0 mg-S/L, depending on the time of a day. Batch test results showed that the RWC did not change the sulfate-reducing activity of sewer biofilms, the increased sulfide production being mainly due to longer hydraulic retention time (HRT). pH in the RWC system was about 0.2 units lower than that in the normal system, indicating that more sulfide would be in molecular form under the RWC condition, which would result in increased sulfide emission to the atmosphere as confirmed by the model simulation. Model based analysis showed that the cost for chemical dosage for sulfide mitigation would increase significantly per unit volume of sewage, although the total cost would decrease due to a lower sewage flow. The dissolved methane concentration under the RWC condition was over two times higher than that under the normal flow condition and the total methane discharge was about 1.5 times higher, which would potentially result in higher greenhouse gas emissions. Batch tests showed that the methanogenic activity of sewer biofilms increased under the RWC condition, which along with the longer HRT, led to increased methane production. Copyright © 2015 Elsevier Ltd. All rights reserved.

SEWER PIPELINE PERFORMANCE INDICATORS

EPA Science Inventory

Wastewater collection systems are an extensive part of the nation's infrastructure. In the United States, approximately 150 million people are served by about 19,000 municipal wastewater collection systems representing about 500,000 miles of sewer pipe (not including privately o...

Integrated modelling for the evaluation of infiltration effects.

PubMed

Schulz, N; Baur, R; Krebs, P

2005-01-01

The objective of the present study is the estimation of the potential benefits of sewer pipe rehabilitation for the performance of the drainage system and the wastewater treatment plant (WWTP) as well as for the receiving water quality. The relation of sewer system status and the infiltration rate is assessed based on statistical analysis of 470 km of CCTV (Closed Circuit Television) inspected sewers of the city of Dresden. The potential reduction of infiltration rates and the consequent performance improvements of the urban wastewater system are simulated as a function of rehabilitation activities in the network. The integrated model is applied to an artificial system with input from a real sewer network. In this paper, the general design of the integrated model and its data requirements are presented. For an exemplary study, the consequences of the simulations are discussed with respect to the prioritisation of rehabilitation activities in the network.

Stochastic modeling of total suspended solids (TSS) in urban areas during rain events.

PubMed

Rossi, Luca; Krejci, Vladimir; Rauch, Wolfgang; Kreikenbaum, Simon; Fankhauser, Rolf; Gujer, Willi

2005-10-01

The load of total suspended solids (TSS) is one of the most important parameters for evaluating wet-weather pollution in urban sanitation systems. In fact, pollutants such as heavy metals, polycyclic aromatic hydrocarbons (PAHs), phosphorous and organic compounds are adsorbed onto these particles so that a high TSS load indicates the potential impact on the receiving waters. In this paper, a stochastic model is proposed to estimate the TSS load and its dynamics during rain events. Information on the various simulated processes was extracted from different studies of TSS in urban areas. The model thus predicts the probability of TSS loads arising from combined sewer overflows (CSOs) in combined sewer systems as well as from stormwater in separate sewer systems in addition to the amount of TSS retained in treatment devices in both sewer systems. The results of this TSS model illustrate the potential of the stochastic modeling approach for assessing environmental problems.

33 CFR 238.6 - General policy.

Code of Federal Regulations, 2010 CFR

2010-07-01

... system of pipes traditionally recognized as a storm drainage system. Flood damage reduction works... ditches with carrying capacities typical of storm sewer pipes. Location of political boundaries will not... the Corps of Engineers. (2) Construction of storm sewer systems and components thereof will be a non...

33 CFR 238.6 - General policy.

Code of Federal Regulations, 2012 CFR

2012-07-01

... system of pipes traditionally recognized as a storm drainage system. Flood damage reduction works... ditches with carrying capacities typical of storm sewer pipes. Location of political boundaries will not... the Corps of Engineers. (2) Construction of storm sewer systems and components thereof will be a non...

33 CFR 238.6 - General policy.

Code of Federal Regulations, 2014 CFR

2014-07-01

... system of pipes traditionally recognized as a storm drainage system. Flood damage reduction works... ditches with carrying capacities typical of storm sewer pipes. Location of political boundaries will not... the Corps of Engineers. (2) Construction of storm sewer systems and components thereof will be a non...

33 CFR 238.6 - General policy.

Code of Federal Regulations, 2011 CFR

2011-07-01

... system of pipes traditionally recognized as a storm drainage system. Flood damage reduction works... ditches with carrying capacities typical of storm sewer pipes. Location of political boundaries will not... the Corps of Engineers. (2) Construction of storm sewer systems and components thereof will be a non...

33 CFR 238.6 - General policy.

Code of Federal Regulations, 2013 CFR

2013-07-01

... system of pipes traditionally recognized as a storm drainage system. Flood damage reduction works... ditches with carrying capacities typical of storm sewer pipes. Location of political boundaries will not... the Corps of Engineers. (2) Construction of storm sewer systems and components thereof will be a non...

Impact of an intense combined sewer overflow event on the microbiological water quality of the Seine River.

PubMed

Passerat, Julien; Ouattara, Nouho Koffi; Mouchel, Jean-Marie; Rocher, Vincent; Servais, Pierre

2011-01-01

For a better understanding of the short and mid-term impacts of a combined sewer overflow (CSO) on the microbiological quality of the receiving river, we studied the composition of a CSO discharge and monitored during several hours the changes in the concentration of fecal indicator bacteria (FIB) in the impacted river water mass. The CSO occurred at the Clichy outfall (Paris agglomeration, France) in summer 2008 as a result of the most intense rainfall of the year. In 6h, 578, 705 m(3) of sewage and 124 t of suspended matter (SM) were discharged into the Seine River. The CSO contained 1.5 × 10(6)E. coli and 4.0 × 10(5) intestinal enterococci per 100 mL on average, and 77% of the E. coli were attached to SM. It was estimated that 89% of the CSO discharge was contributed by surface water runoff, and that resuspension of sewer sediment contributed to ∼75% of the SM, 10-70% of the E. coli and 40-80% of the intestinal enterococci. Directly downstream from the CSO outfall, FIB concentrations in the impacted water mass of the Seine River (2.9 × 10(5)E. coli and 7.6 × 10(4) intestinal enterococci per 100 mL) exceeded by two orders of magnitude the usual dry weather concentrations. After 13-14 h of transit, these concentrations had decreased by 66% for E. coli and 79% for intestinal enterococci. This decline was well accounted for by our estimations of dilution, decay resulting from mortality or loss of culturability and sedimentation of the attached fraction of FIB. Copyright © 2010 Elsevier Ltd. All rights reserved.

Biological assessment and streambed-sediment chemistry of streams in the Indianapolis metropolitan area, Indiana, 2003–2008

USGS Publications Warehouse

Voelker, David C.

2012-01-01

During 2003–2008, the U.S. Geological Survey sampled 13 sites in the Indianapolis metropolitan area in Indiana for benthic invertebrates, fish communities, and streambed-sediment chemistry. Data from seven White River sites and six tributary sites complement surface-water chemistry data collected by the Indianapolis Department of Public Works. The information is being used to assess changes in water quality in conjunction with the City's programs to reduce combined sewer overflows and other point and nonpoint sources of pollution in the Indianapolis area. During the study, 233 benthic-invertebrate taxa were identified from which the Ephemeroptera, Plecoptera, and Trichoptera (EPT) Index, the Hilsenhoff Biotic Index (HBI), and the Invertebrate Community Index (ICI) were calculated. EPT index scores ranged from 2 to 16 on the White River and from 2 to 17 on the tributaries. EPT index scores indicate that these pollution-intolerant taxa are more prevalent upstream from and away from the combined-sewer areas of Indianapolis. HBI scores from sites on the White River ranged from 4.67 (good) to 9.55 (very poor), whereas on the tributaries, scores ranged from 4.21 (very good) to 8.14 (poor). Lower HBI scores suggest that less organic pollution was present and, like the EPT scores, indicate better conditions where combined-sewer overflows (CSOs) are not present. Similarly, ICI scores indicated better conditions upstream from the CSO outfalls on the White River. White River scores ranged from 12 to 46, where higher ICI scores indicate better conditions in the benthic-invertebrate community. ICI scores at the tributary sites ranged from 12 to 52, with the highest scores on streams without CSOs.

Modelling the effects of on-site greywater reuse and low flush toilets on municipal sewer systems.

PubMed

Penn, R; Schütze, M; Friedler, E

2013-01-15

On-site greywater reuse (GWR) and installation of water-efficient toilets (WET) reduce urban freshwater demand. Research on GWR and WET has generally overlooked the effects that GWR may have on municipal sewer systems. This paper discusses and quantifies these effects. The effects of GWR and WET, positive and negative, were studied by modelling a representative urban sewer system. GWR scenarios were modelled and analysed using the SIMBA simulation system. The results show that, as expected, the flow, velocity and proportional depth decrease as GWR increases. Nevertheless, the reduction is not evenly distributed throughout the day but mainly occurs during the morning and evening peaks. Examination of the effects of reduced toilet flush volumes revealed that in some of the GWR scenarios flows, velocities and proportional depths in the sewer were reduced, while in other GWR scenarios discharge volumes, velocities and proportional depths did not change. Further, it is indicated that as a result of GWR and installation of WET, sewer blockage rates are not expected to increase significantly. The results support the option to construct new sewer systems with smaller pipe diameters. The analysis shows that as the penetration of GWR systems increase, and with the installation of WET, concentrations of pollutants also increase. In GWR scenarios (when toilet flush volume is not reduced) the increase in pollutant concentrations is lower than the proportional reduction of sewage flow. Moreover, the results show that the spatial distribution of houses reusing GW does not significantly affect the parameters examined. Copyright © 2012 Elsevier Ltd. All rights reserved.

Degradability of creatinine under sewer conditions affects its potential to be used as biomarker in sewage epidemiology.

PubMed

Thai, Phong K; O'Brien, Jake; Jiang, Guangming; Gernjak, Wolfgang; Yuan, Zhiguo; Eaglesham, Geoff; Mueller, Jochen F

2014-05-15

Creatinine was proposed to be used as a population normalising factor in sewage epidemiology but its stability in the sewer system has not been assessed. This study thus aimed to evaluate the fate of creatinine under different sewer conditions using laboratory sewer reactors. The results showed that while creatinine was stable in wastewater only, it degraded quickly in reactors with the presence of sewer biofilms. The degradation followed first order kinetics with significantly higher rate in rising main condition than in gravity sewer condition. Additionally, daily loads of creatinine were determined in wastewater samples collected on Census day from 10 wastewater treatment plants around Australia. The measured loads of creatinine from those samples were much lower than expected and did not correlate with the populations across the sampled treatment plants. The results suggested that creatinine may not be a suitable biomarker for population normalisation purpose in sewage epidemiology, especially in sewer catchment with high percentage of rising mains. Copyright © 2014 Elsevier Ltd. All rights reserved.

Implication of climate change on urban drainage systems of Chicago and Mainstream and DesPlaines (MS/DP) Tunnel and Reservoir Plan (TARP)

NASA Astrophysics Data System (ADS)

Luo, H.; Schmidt, A.; Garcia, M. H.; Oberg, N.

2016-12-01

The impact of changing climate patterns and rainfall extremes on sewer system and river basin has been brought to attention to the researchers worldwide. In 1972, the Metropolitan Water Reclamation District of Greater Chicago (MWRDGC) adopted the Tunnel and Reservoir Plan (TARP) to address combined sewer overflow (CSO) pollution and flooding problems in the Chicago land area. The hydrosystem laboratory in University of Illinois at Urbana-Champaign developed a series of numerical models accordingly to analyze the complex hydraulic behavior of the as-built TARP system. Due to the interconnected nature of City of Chicago sewer network and MS/DP TARP system, a tightly coupled hydrological and hydraulic model MetroFlow was developed to facilitate such analysis by integrating previous developed models. This study utilized MetroFlow to predict the hydrologic/hydraulic response of the system for a set of pre-determined design and historical storm events. Accordingly, combined sewer overflows (CSO) of Chicago combined sewer system and MS/DP TARP system were evaluated under current and future weather scenarios. The total CSOs from TARP system can be considered as urban point pollution source to the surrounding receiving bodies, hence the potential impact of climate change on CSO fluxes is essential reference to wastewater infrastructure design and operations of the hydraulic regulating structures under storm events to mitigate predicted risks.

D.C. Municipal Separate Storm Sewer System (MS4)

EPA Pesticide Factsheets

This permit covers all areas within the jurisdictional boundary of the District of Columbia served by, or otherwise contributing to discharges from, the Municipal Separate Storm Sewer System (MS4) owned or operated by the District of Columbia.

OPIMIZATION OF COMBINED SEWER OVERFLOW CONTROL SYSTEMS

EPA Science Inventory

The highly variable and intermittent pollutant concentrations and flowrates associated with wet-weather events in combined sewersheds necessitates the use of storage-treatment systems to control pollution. A strategy should be adopted to develop an optimized combined sewer overfl...

40 CFR 35.927-2 - Sewer system evaluation survey.

Code of Federal Regulations, 2014 CFR

2014-07-01

... FEDERAL ASSISTANCE STATE AND LOCAL ASSISTANCE Grants for Construction of Treatment Works-Clean Water Act... transportation and treatment for each defined source of infiltration/inflow. (b) A report shall summarize the... sewer system to eliminate all defined excessive infiltration/inflow. ...

St. Francis Rain Garden Water Quality Sampling Interim Data Report; Total Nitrogen, Total Phosphorus, Sediments or Solids, and E. Coli for the period April to June, 2014

EPA Science Inventory

This interim data reported is being provided per request to the Metropolitan Sewer District (MSD) to provide summary statistics on a limited set of water quality parameters as measured at the St. Francis Rain Garden site in the Lick Run Valley as it pertains to MSD's Project Grou...

SAFL Baffle retrofit for suspended sediment removal in storm sewer sumps.

PubMed

Howard, Adam; Mohseni, Omid; Gulliver, John; Stefan, Heinz

2011-11-15

Standard sumps (manholes) provide a location for pipe junctions and maintenance access in stormwater drainage systems. Standard sumps can also remove sand and silt particles from stormwater, but have a high propensity for washout of the collected sediment. With appropriate maintenance these sumps may qualify as a stormwater best management practice (BMP) device for the removal of suspended sediment from stormwater runoff. To decrease the maintenance frequency and prevent standard sumps from becoming a source of suspended sediment under high flow conditions, a porous baffle, named the SAFL Baffle, has been designed and tested as a retrofit to the sump. Multiple configurations with varying percent open area and different angles of attack were evaluated in scale models. An optimum configuration was then constructed at the prototype scale and evaluated for both removal efficiency and washout. Results obtained with the retrofit indicate that with the right baffle dimensions and porosity, sediment washout from the sump at high flow rates can be almost eliminated, and removal efficiency can be significantly increased at low flow rates. Removal efficiency and washout functions have been developed for standard sumps retrofitted with the SAFL Baffle. The results of this research provide a new, versatile stormwater treatment device and implemented new washout and removal efficiency testing procedures that will improve research and development of stormwater treatment devices. Copyright © 2011 Elsevier Ltd. All rights reserved.

An Environmental Innovation: The Sewer Mouse

NASA Technical Reports Server (NTRS)

1979-01-01

In the effort to clean up America's waters, there is a little-known complicating factor: because they leak, sewer systems in many American cities are causing rather than preventing pollution of rivers and lakes. Fixing the leaks is difficult because their locations are unknown. Maintenance crews can't tear up a whole city looking for cracks in the pipes; they must first determine which areas are most likely suspects. An aerospace spinoff is providing help in that regard. The problem starts with heavy rains. Rainwater naturally flows into the sewers from streets, but sewage systems are designed to accommodate it. However, they are not designed to handle the additional flow of "groundwater", rain absorbed by the earth which seeps into the sewers through leaks in pipes and sewer walls. After a storm, groundwater seepage can increase the waterflow to deluge proportions, with the result that sewage treatment plants are incapable of processing the swollen flow. When that happens the sluices must be opened, dumping raw sewage into rivers and lakes.

Characteristics of the overflow pollution of storm drains with inappropriate sewage entry.

PubMed

Yin, Hailong; Lu, Yi; Xu, Zuxin; Li, Huaizheng; Schwegler, Benedict R

2017-02-01

To probe the overflow pollution of separate storm drains with inappropriate sewage entries, in terms of the relationship between sewage entries and the corresponding dry-weather and wet-weather overflow, the monitoring activities were conducted in a storm drainage system in the Shanghai downtown area (374 ha). In this study site, samples from inappropriately entered dry-weather sewage and the overflow due to storm pumps operation on dry-weather and wet-weather days were collected and then monitored for six water quality constituents. It was found that overflow concentrations of dry-weather period could be higher than those of wet-weather period; under wet-weather period, the overflow concentrations of storm drains were close to or even higher than that of combined sewers. Relatively strong first flush mostly occurred under heavy rain that satisfied critical rainfall amount, maximum rainfall intensity, and maximum pumping discharge, while almost no first flush effect or only weak first flush effect was found for the other rainfall events. Such phenomenon was attributed to lower in-line pipe storage as compared to that of the combined sewers, and serious sediment accumulation within the storm pipes due to sewage entry. For this kind of system, treating a continuous overflow rate is a better strategy than treating the maximum amount of early part of the overflow. Correcting the key inappropriate sewage entries into storm drains should also be focused.

Multi-element sewer slime impact pattern--a quantitative characteristic enabling identification of the source of heavy metal discharges into sewer systems.

PubMed

Kintrup, J; Wünsch, G

2001-11-01

The capability of sewer slime to accumulate heavy metals from municipal wastewater can be exploited to identify the sources of sewage sludge pollution. Former investigations of sewer slime looked for a few elements only and could, therefore, not account for deviations of the enrichment efficiency of the slime or for irregularities from sampling. Results of ICP-MS multi element determinations were analyzed by multivariate statistical methods. A new dimensionless characteristic "sewer slime impact" is proposed, which is zero for unloaded samples. Patterns expressed in this data format specifically extract the information required to identify the type of pollution and polluter quicker and with less effort and cost than hitherto.

MANUAL: REAL TIME CONTROL OF COMBINED SEWERS

EPA Science Inventory

Managers, engineers, and operators of combined urban sewer systems are faced with difficult problems related to the operation and maintenance of their facilities. In addition to the issues related to the operation and upkeep of the system, many sewerage agencies are facing increa...

EXFILTRATION IN SEWER SYSTEMS: IS IT A NATIONAL PROBLEM?

EPA Science Inventory

Many municipalities throughout the US have sewerage systems (separate and combined) that may experience exfiltration of untreated wastewater. This study was conducted to focus on the magnitude of the exfiltration problem from sewer pipes on a national basis. The method for estima...

EXFILTRATION IN SANITARY SEWER SYSTEMS IN THE U.S.

EPA Science Inventory

Many municipalities throughout the US have sewerage systems (separate and combined) that may experience exfiltration of untreated wastewater. This study was conducted to focus on the magnitude of the exfiltration problem from sewer pipes on a national basis. The method for estima...

NPDES Permit for Air Force Academy Municipal Separate Storm Sewer System in Colorado

EPA Pesticide Factsheets

Under NPDES permit CO-R042007, the U.S. Air Force Academy is authorized to discharge from all municipal separate storm sewer system outfalls to the receiving waters specified in the permit in El Paso County, Colorado.

Monitoring the performance of a storm water separating manifold with distributed temperature sensing.

PubMed

Langeveld, J G; de Haan, C; Klootwijk, M; Schilperoort, R P S

2012-01-01

Storm water separating manifolds in house connections have been introduced as a cost effective solution to disconnect impervious areas from combined sewers. Such manifolds have been applied by the municipality of Breda, the Netherlands. In order to investigate the performance of the manifolds, a monitoring technique (distributed temperature sensing or DTS) using fiber optic cables has been applied in the sewer system of Breda. This paper describes the application of DTS as a research tool in sewer systems. DTS proves to be a powerful tool to monitor the performance of (parts of) a sewer system in time and space. The research project showed that DTS is capable of monitoring the performance of house connections and identifying locations of inflow of both sewage and storm runoff. The research results show that the performance of storm water separating manifolds varies over time, thus making them unreliable.

Flow measurements in sewers based on image analysis: automatic flow velocity algorithm.

PubMed

Jeanbourquin, D; Sage, D; Nguyen, L; Schaeli, B; Kayal, S; Barry, D A; Rossi, L

2011-01-01

Discharges of combined sewer overflows (CSOs) and stormwater are recognized as an important source of environmental contamination. However, the harsh sewer environment and particular hydraulic conditions during rain events reduce the reliability of traditional flow measurement probes. An in situ system for sewer water flow monitoring based on video images was evaluated. Algorithms to determine water velocities were developed based on image-processing techniques. The image-based water velocity algorithm identifies surface features and measures their positions with respect to real world coordinates. A web-based user interface and a three-tier system architecture enable remote configuration of the cameras and the image-processing algorithms in order to calculate automatically flow velocity on-line. Results of investigations conducted in a CSO are presented. The system was found to measure reliably water velocities, thereby providing the means to understand particular hydraulic behaviors.

Multivariate probability distribution for sewer system vulnerability assessment under data-limited conditions.

PubMed

Del Giudice, G; Padulano, R; Siciliano, D

2016-01-01

The lack of geometrical and hydraulic information about sewer networks often excludes the adoption of in-deep modeling tools to obtain prioritization strategies for funds management. The present paper describes a novel statistical procedure for defining the prioritization scheme for preventive maintenance strategies based on a small sample of failure data collected by the Sewer Office of the Municipality of Naples (IT). Novelty issues involve, among others, considering sewer parameters as continuous statistical variables and accounting for their interdependences. After a statistical analysis of maintenance interventions, the most important available factors affecting the process are selected and their mutual correlations identified. Then, after a Box-Cox transformation of the original variables, a methodology is provided for the evaluation of a vulnerability map of the sewer network by adopting a joint multivariate normal distribution with different parameter sets. The goodness-of-fit is eventually tested for each distribution by means of a multivariate plotting position. The developed methodology is expected to assist municipal engineers in identifying critical sewers, prioritizing sewer inspections in order to fulfill rehabilitation requirements.

State of Technology Report for Force Main Rehabilitation

EPA Science Inventory

Force mains that carry sewage flows under pressure represent a special set of challenges for sewer rehabilitation. Force mains represent about 7.5% of the wastewater system and they typically use materials that are not commonly used in gravity sewer systems. Ductile iron (DI), ...

SEMINAR PUBLICATION: NATIONAL CONFERENCE ON SANITARY SEWER OVERFLOWS (SSOS)

EPA Science Inventory

This seminar publication presents selected peer-reviewed papers from the conference. Thousands of municipalities across the nation are serviced by separate sanitary sewer systems. A chronic problem that faces many of these systems is the occurrence of SSOs, caused mainly by the i...

NPDES Permit for Fort Carson Municipal Separate Storm Sewer System in Colorado

EPA Pesticide Factsheets

Under NPDES permit CO-R042001, Fort Carson is authorized to discharge from all municipal separate storm sewer system outfalls to receiving waters which include B-Ditch, Clover Ditch, Infantry Creek, Rock Creek, and others in El Paso County, Colorado.

NPDES Permit for Denver VA Hospital Municipal Separate Storm Sewer System in Colorado

EPA Pesticide Factsheets

Under NPDES permit CO-R042008, the Veterans Administration (Medical Center, Denver Campus) is authorized to discharge from all municipal separate storm sewer system outfalls to the receiving waters specified in the permit in the City of Denver, Colorado.

STREET SURFACE STORAGE FOR CONTROL OF COMBINED SEWER SURCHARGE

EPA Science Inventory

One type of Best Management Practices (BMPs) available is the use of street storage systems to prevent combined sewer surcharging and to mitigate basement flooding. A case study approach, based primarily on two largely implemented street storage systems, will be used to explain ...

78 FR 25435 - Draft National Pollutant Discharge Elimination System (NPDES) General Permit for Municipal...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-05-01

... (NPDES) General Permit for Municipal Separate Storm Sewer Systems in the Middle Rio Grande Watershed in... Elimination System (NPDES) general permit for storm water discharges from municipal separate storm sewer... issued for various categories of storm water discharges. Section 402(p)(2) requires permits for five...

Surface wastewater in Samara and their impact on water basins as water supply sources

NASA Astrophysics Data System (ADS)

Strelkov, Alexander; Shuvalov, Mikhail; Gridneva, Marina

2017-10-01

The paper gives an overview of surface wastewater outlets in Samara through the rainwater sewer system into the Saratov water reservoir and the Samara river. The rainwater sewer system in Samara is designed and executed according to a separate scheme, except for the old part of the city, where surface run-off is dumped into the sewer system through siphoned drain. The rainwater system disposes of surface, drainage, industrial clean-contamined waters, emergency and technology discharges from the city’s heat supply and water supply systems. The effluent discharge is carried out by means of separate wastewater outlets into ravines or directly into the Samara river and the Saratov water reservoir without cleaning. The effluent discharge is carried out through the rainwater sewer system with 17 wastewater outlets into the Saratov water reservoir. In the Samara river, surface runoff drainage and clean-contamined water of industrial enterprises is carried out through 14 wastewater outlets. This study emphasizes the demand to arrange effluent discharge and construction of sewage treatment plants to prevent contamination of water objects by surface run-off from residential areas and industrial territories.

Physical disintegration of toilet papers in wastewater systems: experimental analysis and mathematical modeling.

PubMed

Eren, Beytullah; Karadagli, Fatih

2012-03-06

Physical disintegration of representative toilet papers was investigated in this study to assess their disintegration potential in sewer systems. Characterization of toilet papers from different parts of the world indicated two main categories as premium and average quality. Physical disintegration experiments were conducted with representative products from each category according to standard protocols with improvements. The experimental results were simulated by mathematical model to estimate best-fit values of disintegration rate coefficients and fractional distribution ratios. Our results from mathematical modeling and experimental work show that premium products release more amounts of small fibers and disintegrate more slowly than average ones. Comparison of the toilet papers with the tampon applicators studied previously indicates that premium quality toilet papers present significant potential to persist in sewer pipes. Comparison of turbulence level in our experimental setup with those of partial flow conditions in sewer pipes indicates that drains and small sewer pipes are critical sections where disintegration of toilet papers will be limited. For improvement, requirements for minimum pipe slopes may be increased to sustain transport and disintegration of flushable products in small pipes. In parallel, toilet papers can be improved to disintegrate rapidly in sewer systems, while they meet consumer expectations.

Design and performance evaluation of a simplified dynamic model for combined sewer overflows in pumped sewer systems

NASA Astrophysics Data System (ADS)

van Daal-Rombouts, Petra; Sun, Siao; Langeveld, Jeroen; Bertrand-Krajewski, Jean-Luc; Clemens, François

2016-07-01

Optimisation or real time control (RTC) studies in wastewater systems increasingly require rapid simulations of sewer systems in extensive catchments. To reduce the simulation time calibrated simplified models are applied, with the performance generally based on the goodness of fit of the calibration. In this research the performance of three simplified and a full hydrodynamic (FH) model for two catchments are compared based on the correct determination of CSO event occurrences and of the total discharged volumes to the surface water. Simplified model M1 consists of a rainfall runoff outflow (RRO) model only. M2 combines the RRO model with a static reservoir model for the sewer behaviour. M3 comprises the RRO model and a dynamic reservoir model. The dynamic reservoir characteristics were derived from FH model simulations. It was found that M2 and M3 are able to describe the sewer behaviour of the catchments, contrary to M1. The preferred model structure depends on the quality of the information (geometrical database and monitoring data) available for the design and calibration of the model. Finally, calibrated simplified models are shown to be preferable to uncalibrated FH models when performing optimisation or RTC studies.

Dynamic online sewer modelling in Helsingborg.

PubMed

Hernebring, C; Jönsson, L E; Thorén, U B; Møller, A

2002-01-01

Within the last decade, the sewer system in Helsingborg, Sweden has been rehabilitated in many ways along with the reconstruction of the WWTP Oresundsverket in order to obtain a high degree of nitrogen and phosphorus removal. In that context a holistic view has been applied in order to optimise the corrective measures as seen from the effects in the receiving waters. A sewer catchment model has been used to evaluate several operation strategies and the effect of introducing RTC. Recently, a MOUSE ONLINE system was installed. In this phase the objective is to establish a stable communication with the SCADA system and to generate short-term flow forecasts.

SSOAP - A USEPA TOOLBOX FOR SSO ANALYSIS AND CONTROL PLANNING

EPA Science Inventory

Rainfall Derived Infiltration and Inflow (RDII) into sanitary sewer systems has long been recognized as a source of operating problems in sewerage systems. RDII is the main cause of sanitary sewer overflows (SSOs) to basements, streets, or nearby streams and can also cause seriou...

40 CFR 35.927 - Sewer system evaluation and rehabilitation.

Code of Federal Regulations, 2014 CFR

2014-07-01

... excessive infiltration/inflow. A determination of whether excessive infiltration/inflow exists may take into... excessive infiltration/inflow exists. It will consist of: (1) Certification by the State agency, as appropriate; and, when necessary, (2) An infiltration/inflow analysis; and, if appropriate, (3) A sewer system...

40 CFR 35.927 - Sewer system evaluation and rehabilitation.

Code of Federal Regulations, 2010 CFR

2010-07-01

... excessive infiltration/inflow. A determination of whether excessive infiltration/inflow exists may take into... excessive infiltration/inflow exists. It will consist of: (1) Certification by the State agency, as appropriate; and, when necessary, (2) An infiltration/inflow analysis; and, if appropriate, (3) A sewer system...

40 CFR 35.927 - Sewer system evaluation and rehabilitation.

Code of Federal Regulations, 2012 CFR

2012-07-01

... excessive infiltration/inflow. A determination of whether excessive infiltration/inflow exists may take into... excessive infiltration/inflow exists. It will consist of: (1) Certification by the State agency, as appropriate; and, when necessary, (2) An infiltration/inflow analysis; and, if appropriate, (3) A sewer system...

40 CFR 35.927 - Sewer system evaluation and rehabilitation.

Code of Federal Regulations, 2013 CFR

2013-07-01

... excessive infiltration/inflow. A determination of whether excessive infiltration/inflow exists may take into... excessive infiltration/inflow exists. It will consist of: (1) Certification by the State agency, as appropriate; and, when necessary, (2) An infiltration/inflow analysis; and, if appropriate, (3) A sewer system...

40 CFR 35.927 - Sewer system evaluation and rehabilitation.

Code of Federal Regulations, 2011 CFR

2011-07-01

... excessive infiltration/inflow. A determination of whether excessive infiltration/inflow exists may take into... excessive infiltration/inflow exists. It will consist of: (1) Certification by the State agency, as appropriate; and, when necessary, (2) An infiltration/inflow analysis; and, if appropriate, (3) A sewer system...

NPDES Permit for Peterson Air Force Base Municipal Separate Storm Sewer System in Colorado

EPA Pesticide Factsheets

NPDES permit CO-R042006, authorizes Peterson AFB to discharge from all municipal separate storm sewer system outfalls to receiving waters which include the East Fork of Sand Creek and others within exterior AFB boundaries in El Paso County, Colorado.

40 CFR 35.2208 - Adoption of sewer use ordinance and user charge system.

Code of Federal Regulations, 2010 CFR

2010-07-01

... works is placed in operation. Further, the grantee shall implement the user charge system and sewer use ordinance for the useful life of the treatment works. ... GRANTS AND OTHER FEDERAL ASSISTANCE STATE AND LOCAL ASSISTANCE Grants for Construction of Treatment Works...

Leveraging Spatial Data to Assess Where Sewers Leak and Impinge on Urban Water Quality

NASA Astrophysics Data System (ADS)

Holden, P. A.; Roehrdanz, P.; Lee, D. G.; Feraud, M.; Maier, M.; Means, J. C.; Snyder, S.

2017-12-01

In the modern urban water environment (UWE), engineered systems provide wastewater collection, treatment, and reuse; stormwater and graywater management; and potable water treatment, distribution and conservation. Underpinning such systems are physical, private and public, infrastructures whose integrities impinge on major goals of protecting groundwater and surface water resources, managing flooding, and securing safe drinking water. Here we study sanitary sewers, i.e. the main pipes in wastewater collection systems that improve public health by reducing pathogen exposure, and that afford reclaiming water for beneficial reuse. We ask: what is the relationship between sanitary sewer integrity and nearby water quality? Research methods include acquiring spatially defined sewer metadata that are analyzed using a published pipe leakage algorithm with variables of age, depth, materials of construction, length, diameter, slope, and nature of overburden. By executing the algorithm within a geographical information system (GIS), coupled with relating leakage probabilities to shallow groundwater table proximities—also digitally assembled, from well depth data—maps of wastewater exfiltration scores were produced for a city. Field sampling shallow groundwater allowed assessing concentrations of wastewater indicator compounds including personal care products and pharmaceuticals (PCPPs), and showing positive relationships between wastewater exfiltration scores and tryptophan-like fluorescence (TLF), reactive nitrogen species, an artificial sweetener acesulfame, and a stable isotope of oxygen (δ18O). The approach is extended to surface waters, where exfiltrating wastewater may transport from leaking sanitary sewers through the unsaturated zone to nearby storm drains or to storm drains that are submerged in contaminated groundwater. Spatially assessing sewer interactions within the UWE, as such, could aid urban infrastructure management and investment.

A Bayesian network model to assess the public health risk associated with wet weather sewer overflows discharging into waterways.

PubMed

Goulding, R; Jayasuriya, N; Horan, E

2012-10-15

Overflows from sanitary sewers during wet weather, which occur when the hydraulic capacity of the sewer system is exceeded, are considered a potential threat to the ecological and public health of the waterways which receive these overflows. As a result, water retailers in Australia and internationally commit significant resources to manage and abate sewer overflows. However, whilst some studies have contributed to an increased understanding of the impacts and risks associated with these events, they are relatively few in number and there still is a general lack of knowledge in this area. A Bayesian network model to assess the public health risk associated with wet weather sewer overflows is presented in this paper. The Bayesian network approach is shown to provide significant benefits in the assessment of public health risks associated with wet weather sewer overflows. In particular, the ability for the model to account for the uncertainty inherent in sewer overflow events and subsequent impacts through the use of probabilities is a valuable function. In addition, the paper highlights the benefits of the probabilistic inference function of the Bayesian network in prioritising management options to minimise public health risks associated with sewer overflows. Copyright © 2012. Published by Elsevier Ltd.

Simulating groundwater-induced sewer flooding

NASA Astrophysics Data System (ADS)

Mijic, A.; Mansour, M.; Stanic, M.; Jackson, C. R.

2016-12-01

During the last decade, Chalk catchments of southern England experienced severe groundwater flooding. High groundwater levels resulted in the groundwater ingress into the sewer network that led to restricted toilet use and the overflow of diluted, but untreated sewage to road surfaces, rivers and water courses. In response to these events the water and sewerage company Thames Water Utilities Ltd (TWUL) had to allocate significant funds to mitigate the impacts. It was estimated that approximately £19m was spent responding to the extreme wet weather of 2013-14, along with the use of a fleet of over 100 tankers. However, the magnitude of the event was so large that these efforts could not stop the discharge of sewage to the environment. This work presents the analysis of the risk of groundwater-induced sewer flooding within the Chalk catchment of the River Lambourn, Berkshire. A spatially distributed groundwater model was used to assess historic groundwater flood risk and the potential impacts of changes in future climate. We then linked this model to an urban groundwater model to enable us to simulate groundwater-sewer interaction in detail. The modelling setup was used to identify relationships between infiltration into sewers and groundwater levels at specific points on TWUL's sewer network, and to estimate historic and future groundwater flood risk, and how this varies across the catchment. The study showed the significance of understanding the impact of groundwater on the urban water systems, and producing information that can inform a water company's response to groundwater flood risk, their decision making process and their asset management planning. However, the knowledge gained through integrated modelling of groundwater-sewer interactions has highlighted limitations of existing approaches for the simulation of these coupled systems. We conclude this work with number of recommendations about how to improve such hydrological/sewer analysis.

Impacts and managerial implications for sewer systems due to recent changes to inputs in domestic wastewater - A review.

PubMed

Mattsson, Jonathan; Hedström, Annelie; Ashley, Richard M; Viklander, Maria

2015-09-15

Ever since the advent of major sewer construction in the 1850s, the issue of increased solids deposition in sewers due to changes in domestic wastewater inputs has been frequently debated. Three recent changes considered here are the introduction of kitchen sink food waste disposers (FWDs); rising levels of inputs of fat, oil and grease (FOG); and the installation of low-flush toilets (LFTs). In this review these changes have been examined with regard to potential solids depositional impacts on sewer systems and the managerial implications. The review indicates that each of the changes has the potential to cause an increase in solids deposition in sewers and this is likely to be more pronounced for the upstream reaches of networks that serve fewer households than the downstream parts and for specific sewer features such as sags. The review has highlighted the importance of educational campaigns directed to the public to mitigate deposition as many of the observed problems have been linked to domestic behaviour in regard to FOGs, FWDs and toilet flushing. A standardized monitoring procedure of repeat sewer blockage locations can also be a means to identify depositional hot-spots. Interactions between the various changes in inputs in the studies reviewed here indicated an increased potential for blockage formation, but this would need to be further substantiated. As the precise nature of these changes in inputs have been found to be variable, depending on lifestyles and type of installation, the additional problems that may arise pose particular challenges to sewer operators and managers because of the difficulty in generalizing the nature of the changes, particularly where retrofitting projects in households are being considered. The three types of changes to inputs reviewed here highlight the need to consider whether or not more or less solid waste from households should be diverted into sewers. Copyright © 2015 Elsevier Ltd. All rights reserved.

Mortality rates of pathogen indicator microorganisms discharged from point and non-point sources in an urban area.

PubMed

Kim, Geonha; Hur, Jin

2010-01-01

This research measured the mortality rates of pathogen indicator microorganisms discharged from various point and non-point sources in an urban area. Water samples were collected from a domestic sewer, a combined sewer overflow, the effluent of a wastewater treatment plant, and an urban river. Mortality rates of indicator microorganisms in sediment of an urban river were also measured. Mortality rates of indicator microorganisms in domestic sewage, estimated by assuming first order kinetics at 20 degrees C were 0.197 day(-1), 0.234 day(-1), 0.258 day(-1) and 0.276 day(-1) for total coliform, fecal coliform, Escherichia coli, and fecal streptococci, respectively. Effects of temperature, sunlight irradiation and settlement on the mortality rate were measured. Results of this research can be used as input data for water quality modeling or can be used as design factors for treatment facilities.

18 CFR 430.13 - Protected area permits for new withdrawals.

Code of Federal Regulations, 2012 CFR

2012-04-01

... approved by the Commission. (3) A program to monitor and control ground water infiltration to the receiving sewer system. The program must quantify ground water infiltration to the system and document reductions in infiltration. The program should include such measures as leakage surveys of sewer mains, metering...

18 CFR 430.13 - Protected area permits for new withdrawals.

Code of Federal Regulations, 2014 CFR

2014-04-01

... approved by the Commission. (3) A program to monitor and control ground water infiltration to the receiving sewer system. The program must quantify ground water infiltration to the system and document reductions in infiltration. The program should include such measures as leakage surveys of sewer mains, metering...

18 CFR 430.13 - Protected area permits for new withdrawals.

Code of Federal Regulations, 2013 CFR

2013-04-01

... approved by the Commission. (3) A program to monitor and control ground water infiltration to the receiving sewer system. The program must quantify ground water infiltration to the system and document reductions in infiltration. The program should include such measures as leakage surveys of sewer mains, metering...

18 CFR 430.13 - Protected area permits for new withdrawals.

Code of Federal Regulations, 2011 CFR

2011-04-01

... approved by the Commission. (3) A program to monitor and control ground water infiltration to the receiving sewer system. The program must quantify ground water infiltration to the system and document reductions in infiltration. The program should include such measures as leakage surveys of sewer mains, metering...

Sewers as a source and sink of chlorinated-solvent groundwater contamination, Marine Corps Recruit Depot, Parris Island, South Carolina

USGS Publications Warehouse

Vroblesky, D.A.; Petkewich, M.D.; Lowery, M.A.; Landmeyer, J.E.

2011-01-01

Groundwater contamination by tetrachloroethene and its dechlorination products is present in two partially intermingled plumes in the surficial aquifer near a former dry-cleaning facility at Site 45, Marine Corps Recruit Depot, Parris Island, South Carolina. The northern plume originates from the vicinity of former above-ground storage tanks. Free-phase tetrachloroethene from activities in this area entered the groundwater. The southern plume originates at a nearby, new dry-cleaning facility, but probably was the result of contamination released to the aquifer from a leaking sanitary sewer line from the former dry-cleaning facility. Discharge of dissolved groundwater contamination is primarily to leaking storm sewers below the water table. The strong influence of sanitary sewers on source distribution and of storm sewers on plume orientation and discharge at this site indicates that groundwater-contamination investigators should consider the potential influence of sewer systems at their sites. ?? 2011, National Ground Water Association.

Remote Infrared Thermal Sensing of Sewer Voids, Four-Year Update

NASA Astrophysics Data System (ADS)

Weil, Gary J.

1988-01-01

When a sewer caves in, it often takes the street, sidewalks, and surrounding buildings along for the ride. These collapses endanger public health and safety. Repairing a sewer before such a cave-in is obviously the preferred method. Emergency repairs cost far more than prevention measures - often millions of dollars more. Many combined sewers in the St. Louis area, as in many of America's cities, are more than 125 years old and are subject to structural failure. In 1981 alone, St. Louis had 4,000 sewer collapses and an astronomical repair bill. These and similar problems have been described as "a crisis of national proportions. The question addressed by this paper is how to detect unseen problem areas in sewer systems before they give way. At the present, progressive sewer administrations may use crawl crews to inspect sewers when problems are suspected. This can be extremely costly and dangerous, and a void around the outside of the sewer is often invisible from within. Thus, even a crawl crew can fail to detect most voids. Infrared Thermography has been found by sewer districts and independent evaluation engineering firms to be an extremely accurate method of finding sewer voids, before they can cause expensive and dangerous problems. This technique uses a non-contact, remote sensing method, with the potential for surveying large areas quickly and efficiently. This paper reviews our initial paper presented to The International Society for Optical Engineering in October of 1983 and presents an update of our experience, both successes and failures, in several large-scale void detection projects. Infrared Thermographic techniques of non-destructive testing will have major implications for cities and for the engineering profession because it promises to make the crisis of infrastructure repair and rehabilitation more manageable. Intelligent, systematic use of this relatively low cost void detection method, Infrared Thermography, may revolutionize the way sewer problems are handled in the future.

Source, Transport, and Fate of Groundwater Contamination at Site 45, Marine Corps Recruit Depot, Parris Island, South Carolina

USGS Publications Warehouse

Vroblesky, Don A.; Petkewich, Matthew D.; Landmeyer, James E.; Lowery, Mark A.

2009-01-01

Groundwater contamination by tetrachloroethene and its dechlorination products is present in two partially intermingled plumes in the surficial aquifer near a former dry-cleaning facility at Site 45, Marine Corps Recruit Depot, Parris Island, South Carolina. The northern plume originates from the vicinity of former above-ground storage tanks. Free-phase tetrachloroethene from activities in this area entered the groundwater and the storm sewer. The southern plume originates at a nearby new dry-cleaning facility, but probably was the result of contamination released to the aquifer from a leaking sanitary sewer line from the former dry-cleaning facility. Discharge of dissolved groundwater contamination is primarily to leaking storm sewers below the water table. Extensive biodegradation of the contamination takes place in the surficial aquifer; however, the biodegradation is insufficient to reduce trichloroethene to less than milligram-per-liter concentrations prior to discharging into the storm sewers. The groundwater volatile organic compounds entering the storm sewers are substantially diluted by tidal flushing upon entry and are subject to volatilization as they are transported through the storm sewer to a discharge point in a tributary to Ballast Creek. TCE concentrations of about 2-6 micrograms per liter were present in storm-sewer water near the discharge point (sampled at manhole STS26). On three out of four sampling events at manhole STS14, the storm-sewer water contained no vinyl chloride. During a time of relatively high groundwater levels, however, 20 micrograms per liter of vinyl chloride was present in STS14 storm-sewer water. Because groundwater leaks into that storm sewer and because the storm sewer upgradient from manhole STS14 is adjacent to part of the aquifer where 2,290 micrograms per liter of vinyl chloride have been detected, there is a potential for substantially increased concentrations of vinyl chloride to discharge at the storm-sewer outfall under conditions of high groundwater levels and low tidal flushing. In addition, the observation that free-phase tetrachloroethene may have entered the storm-sewer system during the 1994 discharge means that dense nonaqueous phase liquid tetrachloroethene could have leaked from various parts of the storm sewer or discharged to surface water at the storm-sewer outfall.

The U.S. Geological Survey and City of Atlanta water-quality and water-quantity monitoring network

USGS Publications Warehouse

Horowitz, Arthur J.; Hughes, W. Brian

2006-01-01

Population growth and urbanization affect the landscape, and the quality and quantity of water in nearby rivers and streams, as well as downstream receiving waters (Ellis, 1999). Typical impacts include: (1) disruption of the hydrologic cycle through increases in the extent of impervious surfaces (e.g., roads, roofs, sidewalks) that increase the velocity and volume of surface-water runoff; (2) increased chemical loads to local and downstream receiving waters from industrial sources, nonpoint-source runoff, leaking sewer systems, and sewer overflows; (3) direct or indirect soil contamination from industrial sources, power-generating facilities, and landfills; and (4) reduction in the quantity and quality of aquatic habitats. The City of Atlanta's monitoring network consists of 21 long-term sites. Eleven of these are 'fully instrumented' to provide real-time data on water temperature, pH, specific conductance, dissolved oxygen, turbidity (intended as a surrogate for suspended sediment concentration), water level (gage height, intended as a surrogate for discharge), and precipitation. Data are transmitted hourly and are available on a public Web site (http://ga.water.usgs.gov/). Two sites only measure water level and rainfall as an aid to stormwater monitoring. The eight remaining sites are used to assess water quality.

Characterizing the Organic Matter in Surface Sediments from ...

EPA Pesticide Factsheets

The San Juan Bay Estuary (SJBE) is located on the north coast of Puerto Rico and includes the San Juan Bay, San José Lagoon, La Torrecilla Lagoon and Piñones Lagoon, as well as the Martín Peña and the Suárez Canals. The SJBE watershed has the highest density of inhabitants and major industrial activities in Puerto Rico. As a result, the SJBE is impacted by wastewater from combined-sewer overflows, faulty sewer lines, and storm water runoff; these factors combined with trash accumulation and infilling of the Martín Peña canal, contribute to decreased tidal exchange and reduced flushing in the estuary. To quantify the impact of the obstruction of the Martín Peña canal on anthropogenic nutrient distribution in the SJBE, over 200 sediment grab samples were collected throughout the estuary in 2015. The samples were analyzed for carbonate content, organic matter, grain size, bulk density, percent phosphorus, percent nitrogen (%N), and stable isotopes (δ15N and δ13C). The %N values were highest in the surface sediments from the western portion of the Martín Peña canal, where %N was >0.86%. In contrast, %N from the adjacent San José lagoon averaged <0.2%. Grain size distributions across the SJBE were consistent with low flushing in the inner portions of the SJBE. While the Martín Peña canal remains phosphorus limited, N:P ratios suggest the San Juna Bay and San José Lagoon have undergone major ecological shifts in the past two decades. Our

Heavy metal contamination in river water and sediments of the Swarnamukhi River Basin, India: risk assessment and environmental implications.

PubMed

Patel, Priyanka; Raju, N Janardhana; Reddy, B C Sundara Raja; Suresh, U; Sankar, D B; Reddy, T V K

2018-04-01

The concentration of heavy metals was analyzed each of 20 river water, suspended sediments and bed sediments along the stretch of Swarnamukhi River Basin. River water is not contaminated with heavy metals except Fe and Mn. Contamination factor in sediments shows considerable to very high degree contamination with Cr, Cu, Pb and Zn. The sources of these metals could be residential wastes, sewer outfall, fertilizers, pesticides (M-45 + carbondine) and traffic activities apart from natural weathering of granitic rocks present in the basin area. Principal component analyses indicate the interaction between metals in different media. The comparison of metals (Cu, Pb and Zn) in bed sediments of Swarnamukhi River with the Indian and world averages indicates that the values obtained in the basin are above the Indian averages and far below to the world averages. Average shale values and sediment quality guidelines point toward the enrichment and contamination of Cu, Cr, Pb and Zn to several fold leading to eco-toxicological risks in basin.

Assessment of the contribution of sewer deposits to suspended solids loads in combined sewer systems during rain events.

PubMed

Hannouche, A; Chebbo, G; Joannis, C

2014-04-01

Within the French observatories network SOERE "URBIS," databases of continuous turbidity measurements accumulating hundreds of events and many dry weather days are available for two sites with different features (Clichy in Paris and Ecully in Lyon). These measurements, converted into total suspended solids (TSS) concentration using TSS-turbidity relationships and combined with a model of runoff event mean concentration, enable the assessment of the contribution of sewer deposits to wet weather TSS loads observed at the outlet of the two watersheds. Results show that the contribution of sewer deposits to wet weather suspended solid's discharges is important but variable (between 20 and 80 % of the mass at the outlet depending on the event), including a site allegedly free of (coarse) sewer deposits. The uncertainties associated to these results are assessed too.

Pressurized storm sewer simulation : model enhancement.

DOT National Transportation Integrated Search

1991-01-01

A modified Pressurized Flow Simulation Model, PFSM, was developed and attached to the Federal Highway Administration, FHWA, Pool Funded PFP-HYDRA Package. Four hydrograph options are available for simulating inflow to a sewer system under surcharge o...

Measurement of infiltration rates in urban sewer systems by use of oxygen isotopes.

PubMed

De Bénédittis, J; Bertrand-Krajewski, J L

2005-01-01

The paper presents the principle of a method to measure infiltration rates in sewer systems based on the use of oxygen isotopes and its application in Lyon (France). In the urban area of Lyon, significant differences in delta 18O that can reach 3 per thousand are observed between the oxygen isotopic compositions of groundwater originating from Rhone, Saone and from their associated alluvial aquifers. Drinking water supplying Lyon results mainly from pumping in the Rhone alluvial aquifer. Therefore, in some areas, the difference of isotopic composition between wastewater resulting from the consumption of drinking water and local groundwater can be used to measure infiltration in sewer systems. The application in the catchment of Ecully shows that the infiltration flow rate presents strong fluctuations at an hourly scale: it varies between 15 and 40 m3/h. This variability could be explained by non-constant discharges of pumping and by variations of the water level in the sewer.

Superfund Record of Decision (EPA Region 3): Metal Banks, Philadelphia, PA, December 31, 1997

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

1998-09-01

This Record of Decision (ROD) presents the final remedial action selected for the Metal Bank Superfund Site (Site), located in northeastern Philadelphia, Pennsylvania. The remedy addresses contaminated soil, sediment, surface water, and groundwater at the Site and includes: installation of an oil collection system consisting of a sheet pile wall around the southern and western perimeter of the property; installation of temporary cofferdams prior to soil/sediment excavation to minimize transport of contamination into the Delaware River; excavation of contaminated soil within the Courtyard Area within two feet of the surface where polychlorinated biphenyl (PCB) concentrations exceed 10 ppm; disposal ofmore » contaminated soils and sediments that are hazardous; removal and disposal of the underground storage tank and its contents from the Southern Portion of the property; backfilling of excavated areas; posting signs prohibiting consumption of fish caught in the Delaware River in the vicinity of the Site; restrictions on the deed to the property to prevent future residential or agricultural use of the Site, use of the groundwater, and intrusive activities into the subsurface soils below the water table in the Southern Portion of the property; additional investigation to determine whether dense non-aqueous phase liquids (DNAPLs) are present at the Site and whether the storm sewer system in the vicinity of the Site is contaminated; and monitoring of groundwater, the Delaware River, and the Baxter Water intake.« less

THE CHOICE OF REAL-TIME CONTROL STRATEGY FOR COMBINED SEWER OVERFLOW CONTROL

EPA Science Inventory

This paper focuses on the strategies used to operate a collection system in real-time control (RTC) in order to optimize use of system capacity and to reduce the cost of long-term combined sewer overflow (CSO) control. Three RTC strategies were developed and analyzed based on the...

33 CFR 238.7 - Decision criteria for participation.

Code of Federal Regulations, 2013 CFR

2013-07-01

... upstream of the precise point where Federal flood control authorities become applicable. (b) Storm sewer... will be considered to be a part of local storm drainage to be addressed as part of the consideration of an adequate storm sewer system. The purpose of this system is to collect and convey to a natural...

33 CFR 238.7 - Decision criteria for participation.

Code of Federal Regulations, 2014 CFR

2014-07-01

... upstream of the precise point where Federal flood control authorities become applicable. (b) Storm sewer... will be considered to be a part of local storm drainage to be addressed as part of the consideration of an adequate storm sewer system. The purpose of this system is to collect and convey to a natural...

33 CFR 238.7 - Decision criteria for participation.

Code of Federal Regulations, 2012 CFR

2012-07-01

... upstream of the precise point where Federal flood control authorities become applicable. (b) Storm sewer... will be considered to be a part of local storm drainage to be addressed as part of the consideration of an adequate storm sewer system. The purpose of this system is to collect and convey to a natural...

EXFILTRATION IN SEWER SYSTEMS

EPA Science Inventory

This study focused on the quantification of leakage of sanitary and industrial sewage from sanitary sewer pipes on a national basis. The method for estimating exfiltration amounts utilized groundwater talbe information to identify areas of the country where the hydraulic gradient...

A novel approach to model dynamic flow interactions between storm sewer system and overland surface for different land covers in urban areas

NASA Astrophysics Data System (ADS)

Chang, Tsang-Jung; Wang, Chia-Ho; Chen, Albert S.

2015-05-01

In this study, we developed a novel approach to simulate dynamic flow interactions between storm sewers and overland surface for different land covers in urban areas. The proposed approach couples the one-dimensional (1D) sewer flow model (SFM) and the two-dimensional (2D) overland flow model (OFM) with different techniques depending on the land cover type of the study areas. For roads, pavements, plazas, and so forth where rainfall becomes surface runoff before entering the sewer system, the rainfall-runoff process is simulated directly in the 2D OFM, and the runoff is drained to the sewer network via inlets, which is regarded as the input to 1D SFM. For green areas on which rainfall falls into the permeable ground surface and the generated direct runoff traverses terrain, the deduction rate is applied to the rainfall for reflecting the soil infiltration in the 2D OFM. For flat building roofs with drainage facilities allowing rainfall to drain directly from the roof to sewer networks, the rainfall-runoff process is simulated using the hydrological module in the 1D SFM where no rainfall is applied to these areas in the 2D OFM. The 1D SFM is used for hydraulic simulations in the sewer network. Where the flow in the drainage network exceeds its capacity, a surcharge occurs and water may spill onto the ground surface if the pressure head in a manhole exceeds the ground elevation. The overflow discharge from the sewer system is calculated by the 1D SFM and considered a point source in the 2D OFM. The overland flow will return into the sewer network when it reaches an inlet that connects to an un-surcharged manhole. In this case, the inlet is considered as a point sink in the 2D OFM and an inflow to a manhole in the 1D SFM. The proposed approach was compared to other five urban flood modelling techniques with four rainfall events that had previously recorded inundation areas. The merits and drawbacks of each modelling technique were compared and discussed. Based on the simulated results, the proposed approach was found to simulate floodings closer to the survey records than other approaches because the physical rainfall-runoff phenomena in urban environment were better reflected.

A vision-based tool for the control of hydraulic structures in sewer systems

NASA Astrophysics Data System (ADS)

Nguyen, L.; Sage, D.; Kayal, S.; Jeanbourquin, D.; Rossi, L.

2009-04-01

During rain events, the total amount of the wastewater/storm-water mixture cannot be treated in the wastewater treatment plant; the overflowed water goes directly into the environment (lakes, rivers, streams) via devices called combined sewers overflows (CSOs). This water is untreated and is recognized as an important source of pollution. In most cases, the quantity of overflowed water is unknown due to high hydraulic turbulences during rain events; this quantity is often significant. For this reason, the monitoring of the water flow and the water level is of crucial environmental importance. Robust monitoring of sewer systems is a challenging task to achieve. Indeed, the environment inside sewers systems is inherently harsh and hostile: constant humidity of 100%, fast and large water level changes, corrosive atmosphere, presence of gas, difficult access, solid debris inside the flow. A flow monitoring based on traditional probes placed inside the water (such as Doppler flow meter) is difficult to conduct because of the solid material transported by the flow. Probes placed outside the flow such as ultrasonic water level probes are often used; however the measurement is generally done on only one particular point. Experience has shown that the water level in CSOs during rain events is far from being constant due to hydraulic turbulences. Thus, such probes output uncertain information. Moreover, a check of the data reliability is impossible to achieve. The HydroPix system proposes a novel approach to the monitoring of sewers based on video images, without contact with the water flow. The goal of this system is to provide a monitoring tool for wastewater system managers (end-users). The hardware was chosen in order to suit the harsh conditions of sewers system: Cameras are 100% waterproof and corrosion-resistant; Infra-red LED illumination systems are used (waterproof, low power consumption); A waterproof case contains the registration and communication system. The monitoring software has the following requirements: visual analysis of particular hydraulic behavior, automatic vision-based flow measurements, automatic alarm system for particular events (overflows, risk of flooding, etc), database for data management (images, events, measurements, etc.), ability to be controlled remotely. The software is implemented in modular server/client architecture under LabVIEW development system. We have conducted conclusive in situ tests in various sewers configurations (CSOs, storm-water sewerage, WWTP); they have shown the ability of the HydroPix to perform accurate monitoring of hydraulic structures. Visual information demonstrated a better understanding of the flow behavior in complex and difficult environment.

Geomorphological assessment of sediment contamination in an urban stream system

USGS Publications Warehouse

Rhoads, B.L.; Cahill, R.A.

1999-01-01

Little is known about the influence of fluvial-geomorphological features on the dispersal of sediment-related contaminants in urban drainage systems. This study investigates the relation between reach-scale geomorphological conditions and network-scale patterns of trace-element concentrations in a partially urbanized stream system in East-Central Illinois, USA Robust statistical analysis of bulk sediment samples reveals levels of Cr, Cu, Pb, Ni, and Zn exceed contamination thresholds in the portion of the watershed in close proximity to potential sources of pollution-in this case storm-sewer outfalls. Although trace-element concentrations decrease rapidly downstream from these sources, substantial local variability in metal levels exists within contaminated reaches. This local variability is related to reach-scale variation in fluvial-geomorphic conditions, which in turn produces variation in the degree of sorting and organic-matter content of bed material. Metal concentrations at contaminated sites also exhibit considerable variability over time. Analytical tests on specific size fractions of material collected at a highly contaminated site indicate that Cr and Ni are concentrated in the 0.063 to 0.250 mm fraction of the sediment. This fraction also has elevated concentration of Zr. SEM analysis shows that the fine sand fraction contains shards of stainless steel within a matrix of zircon sand, an industrial material associated with a nearby alloy casting operation. Samples of suspended load and bedload at the contaminated site also have elevated amounts of trace metals, but concentrations of Ni and Cr in the bedload are less than concentrations in the bed material, suggesting that these trace elements are relatively immobile. Off the other hand, amounts of CU and Zn in the bedload exceed concentrations in the bed material, implying that these trace metals are preferentially mobilized during transport events.

Sources and contamination rate of port sediments: evidences from dimensional, mineralogical, and chemical investigations

NASA Astrophysics Data System (ADS)

Lucchetti, Gabriella; Cutroneo, Laura; Carbone, Cristina; Consani, Sirio; Vagge, Greta; Canepa, Giuseppe; Capello, Marco

2017-04-01

Ports are complex environments due to their complicated geometry (quays, channels, and piers), the presence of human activities (vessel traffic, yards, industries, and discharges), and natural factors (stream and torrent inputs, sea action, and currents). Due to the many activities that take place in a port, sediments and waters are often contaminated by different kinds of chemicals, such as hydrocarbons, dioxins, pesticides, nutrients, and metals. The contamination rate of a port basin is site specific and depends on the sources of contamination in the nearby urban system as well as the port system itself, such as city discharges and sewers, river intake, vessel traffic, factories (Taylor and Owens, 2009). Moreover, two important sources and vehicles of contaminants are: a) anthropogenic road deposited sediments derived from the runoff of the port and city area, and natural road deposited sediments derived from rivers and torrents, and b) airborne particulate matter and sediments (Taylor and Owens, 2009). The Port of Genoa is situated at the apex of the Ligurian Sea in the north western Mediterranean Sea and is characterised by the presence of several commercial activities that have contributed, over the years, and still contribute today, to the contaminant accumulation in both the water column and the bottom sediments. This port basin includes the mouth of several streams and the mouth of the Bisagno and the Polcevera Torrents, along the banks of which can be found several small towns, quarries, factories, and the suburbs of the city of Genoa, a ferry terminal, different container terminals, marinas, dry docks, the coal power plant of Genoa, and different wastewater treatment plant discharges. Starting from these considerations, we have examined the marine environment of a port from the point of view of the water mass circulation, hydrological characteristics, distribution of the sediment grain size, mineralogical characteristics, and metal concentrations of the bottom sediments. Our results show that, in the case of the Port of Genoa (north western Italy), both the impact of the human activities (such as coal power plant, oil depots, yards, dredging of the bottom sediments, etc.) and the natural processes (such as currents, fresh water and sediment inputs from the torrents), together with the morphology of the basin, are important factors in sediment, water and metal distributions and give rise to a complex environment. Taylor, K.G., Owens, P.N., 2009. Sediments in urban river basins: a review of sediment contaminant dynamics in an environmental system conditioned by human activities. Journal of Soils and Sediments 9: 281-303.

Occurrence and distribution pattern of acidic pharmaceuticals in surface water, wastewater, and sediment of the Msunduzi River, Kwazulu-Natal, South Africa.

PubMed

Agunbiade, Foluso O; Moodley, Brenda

2016-01-01

The paucity of information on the occurrence of pharmaceuticals in the environment in African countries led the authors to investigate 8 acidic pharmaceuticals (4 antipyretics, 3 antibiotics, and 1 lipid regulator) in wastewater, surface water, and sediments from the Msunduzi River in the province of KwaZulu-Natal, South Africa, using solid-phase extraction (SPE) and liquid chromatography-mass spectrometry (LC/MS). The method recoveries, limits of detection (LOD), and limits of quantification were determined. The method recoveries were 58.4% to 103%, and the LODs ranged between 1.16 ng/L and 29.1 ng/L for water and between 0.58 ng/g and 14.5 ng/g for sediment. The drugs were all present in wastewater and in most of the surface water and sediment samples. Aspirin was the most abundant pharmaceutical observed, 118 ± 0.82 μg/L in wastewater influent, and the most observed antibiotic was nalidixic acid (25.2-29.9 μg/L in wastewater); bezafibrate was the least observed. The distribution pattern of the antipyretic in water indicates more impact in suburban sites. The solid-liquid partitioning of the pharmaceuticals between sediment and water, measured as the distribution coefficient (log KD ) gave an average accumulation magnitude of 10× to 32× in sediments than in water. The downstream distribution patterns for both water and sediment indicate discharge contributions from wastewater, agricultural activities, domestic waste disposal, and possible sewer system leakages. Although concentrations of the pharmaceuticals were comparable with those obtained from some other countries, the contamination of the present study site with pharmaceuticals has been over time and continues at present, making effective management and control necessary. © 2015 SETAC.

Effects of sanitary sewers on ground-water levels and streams in Nassau and Suffolk Counties, New York; Part 2, development and application of southwest Suffolk County model

USGS Publications Warehouse

Buxton, H.T.; Reilly, T.E.

1985-01-01

By 1990, sanitary sewers in Nassau County Sewage Disposal Districts 2 and 3 and Suffolk County Southwest Sewer District will discharge to the ocean 140 cu ft of water/sec that would otherwise be returned to the groundwater system through septic tanks and similar systems. To evaluate the effects of this loss on groundwater levels and streamflow, the U.S. Geological Survey developed a groundwater flow model that couples a fine-scale subregional model to a regional model of larger scale. The regional model generates flux boundary conditions for the subregional model, and the subregional model provides detail in the area of concern. Results indicate that the water table will decline by as much as 8 ft along the Suffolk-Nassau county line, with effects decreasing eastward. Base flow is predicted to decrease by as much as 73% in a stream along the county line, but this effect will decrease to zero just east of the sewered area. This report is one of a series describing the predicted hydrologic effects of sewers in southern Nassau and southwest Suffolk Counties. (USGS)

Demonstration of Innovative Sewer System Inspection Technology: SL-RAT

EPA Science Inventory

The overall objective of this EPA-funded study was to demonstrate innovative sewer line assessment technologies that are designed for rapid deployment using portable equipment. This study focused on demonstration of technologies that are suitable for smaller diameter pipes (less ...

USING VISUAL PLUMES PREDICTIONS TO MODULATE COMBINED SEWER OVERFLOW (CSO) RATES

EPA Science Inventory

High concentrations of pathogens and toxic residues in creeks and rivers can pose risks to human health and ecological systems. Combined Sewer Overflows (CSOs) discharging into these watercourses often contribute significantly to elevating pollutant concentrations during wet weat...

High resolution modelling of extreme precipitation events in urban areas

NASA Astrophysics Data System (ADS)

Siemerink, Martijn; Volp, Nicolette; Schuurmans, Wytze; Deckers, Dave

2015-04-01

The present day society needs to adjust to the effects of climate change. More extreme weather conditions are expected, which can lead to longer periods of drought, but also to more extreme precipitation events. Urban water systems are not designed for such extreme events. Most sewer systems are not able to drain the excessive storm water, causing urban flooding. This leads to high economic damage. In order to take appropriate measures against extreme urban storms, detailed knowledge about the behaviour of the urban water system above and below the streets is required. To investigate the behaviour of urban water systems during extreme precipitation events new assessment tools are necessary. These tools should provide a detailed and integral description of the flow in the full domain of overland runoff, sewer flow, surface water flow and groundwater flow. We developed a new assessment tool, called 3Di, which provides detailed insight in the urban water system. This tool is based on a new numerical methodology that can accurately deal with the interaction between overland runoff, sewer flow and surface water flow. A one-dimensional model for the sewer system and open channel flow is fully coupled to a two-dimensional depth-averaged model that simulates the overland flow. The tool uses a subgrid-based approach in order to take high resolution information of the sewer system and of the terrain into account [1, 2]. The combination of using the high resolution information and the subgrid based approach results in an accurate and efficient modelling tool. It is now possible to simulate entire urban water systems using extreme high resolution (0.5m x 0.5m) terrain data in combination with a detailed sewer and surface water network representation. The new tool has been tested in several Dutch cities, such as Rotterdam, Amsterdam and The Hague. We will present the results of an extreme precipitation event in the city of Schiedam (The Netherlands). This city deals with significant soil consolidation and the low-lying areas are prone to urban flooding. The simulation results are compared with measurements in the sewer network. References [1] Guus S. Stelling G.S., 2012. Quadtree flood simulations with subgrid digital elevation models. Water Management 165 (WM1):1329-1354. [2] Vincenzo Cassuli and Guus S. Stelling, 2013. A semi-implicit numerical model for urban drainage systems. International Journal for Numerical Methods in Fluids. Vol. 73:600-614. DOI: 10.1002/fld.3817

Removal of nutrients from combined sewer overflows and lake water in a vertical-flow constructed wetland system.

PubMed

Gervin, L; Brix, H

2001-01-01

Lake Utterslev is situated in a densely built-up area of Copenhagen, and is heavily eutrophicated from combined sewer overflows. At the same time the lake suffers from lack of water. Therefore, a 5,000 m2 vertical flow wetland system was constructed in 1998 to reduce the phosphorus discharge from combined sewer overflows without reducing the water supply to the lake. During dry periods the constructed wetland is used to remove phosphorus from the lake water. The system is designed as a 90 m diameter circular bed with a bed depth of c. 2 m. The system is isolated from the surroundings by a polyethylene membrane. The bed medium consists of a mixture of gravel and crushed marble, which has a high binding capacity for phosphorus. The bed is located within the natural littoral zone of the lake and is planted with common reed (Phragmites australis). The constructed wetland is intermittently loaded with combined sewer overflow water or lake water and, after percolation through the bed medium, the water is collected in a network of drainage pipes at the bottom of the bed and pumped to the lake. The fully automated loading cycle results in alternating wet and dry periods. During the initial two years of operation, the phosphorus removal for combined sewer overflows has been consistently high (94-99% of inflow concentrations). When loaded with lake water, the phosphorus removal has been high during summer (71-97%) and lower during winter (53-75%) partly because of lower inlet concentrations. Effluent phosphorus concentrations are consistently low (0.03-0.04 mg/L). Ammonium nitrogen is nitrified in the constructed wetland, and total suspended solids and COD are generally reduced to concentrations below 5 mg/L and 25 mg/L, respectively. The study documents that a subsurface flow constructed wetland system can be designed and operated to effectively remove phosphorus and other pollutants from combined sewer overflows and eutrophicated lake water.

Assessment of pH shock as a method for controlling sulfide and methane formation in pressure main sewer systems.

PubMed

Gutierrez, Oriol; Sudarjanto, Gatut; Ren, Guo; Ganigué, Ramon; Jiang, Guangming; Yuan, Zhiguo

2014-01-01

Caustic dosing to raise pH above 10.0 for short periods (hours) is often used by water utilities for controlling sulfide formation in sewers. However the effectiveness of this strategy is rarely reported and the impact of pH level and exposure time on the effectiveness is largely unknown. The effectiveness of this strategy under various pH levels (10.5-12.5) and exposure time (0.5-6.0 h) in controlling sulfide and methane production was evaluated in laboratory scale anaerobic sewer reactors and then in a real sewer system. Laboratory studies showed that the sulfide production rate of the laboratory sewer biofilm was reduced by 70-90% upon the completion of the pH shock, while the methane production rate decreased by 95-100%. It took approximately one week for the sulfate-reducing activity to recover to normal levels. In comparison, the methanogenic activities recovered to only about 10% in 4 weeks. The slow recovery is explained by the substantially loss of cell viability upon pH shocks, which recovered slowly after the shocks. Laboratory studies further revealed that a pH level of 10.5 for 1-2 h represent cost-effective conditions for the pH shock treatment. However, field trials showed a higher pH (11.5) and larger dosing times are needed due to the pH decreases along the sewer line and at the two ends of the caustic-receiving wastewater slugs due to dilution. To have effective sulfide and methane control, it is important to ensure effective conditions (pH > 10.5 and duration >1-2 h) for the entire sewer line. Copyright © 2013 Elsevier Ltd. All rights reserved.

Development and implementation of a real-time control strategy for the sewer system of the city of Vienna.

PubMed

Fuchs, L; Beeneken, T

2005-01-01

The paper describes the realization of a real-time control for the Vienna sewer system. The project is scheduled for completion for 2004. The 3.5 year project comprises all planning stages starting with the recording of data up to the planning of measuring and controlling units. The concrete steps of the planning stages are explained. A measuring system including 25 rainfall measurements, 40 flow measurements and 20 water level measurements is implemented as an online system. This measuring system is designed to achieve two objectives, on the one hand the real-time control and on the other hand the calibration of the model that is used for the hydrodynamic sewer system simulation. The approx. 53,000 pipes have served to generate a coarse network of no more than approx. 2600 pipes. The area data were derived with high accuracy from available aerial photograph interpretations. With simulation runs of a rule-based control software the system operation was examined. A self-learning system will improve the rule basis. A forecasting model that uses weather observation radar will additionally influence the controlling decisions. The findings from the investigations are immediately considered in the planning of measuring and control units. The simulated results for the first phase of implementation, which demonstrate the benefit of RTC for the Vienna sewer system, are explained.

Demonstration of an Innovative Large-Diameter Sewer Rehabilitation Technology in Houston, Texas

EPA Science Inventory

While sewer renewal technologies currently being used for the repair, replacement and/or rehabilitation of deteriorating wastewater collection systems are generally effective, there is still room for improvement of existing technologies and for the development of new technologies...

US EPA CSO CAPSTONE REPORT: THE CSO PROBLEM

EPA Science Inventory

The history of combined sewer systems (CSS) and combined sewer overflows (CSOs) in the US provides unique insights into the complex challenge faced in reducing and eliminating their adverse environmental effects. The evolution of the "modern" CSS shows how early urban drainag sys...

Demonstration of an Innovative Large-Diameter Sewer Rehabilitation Technology in Houston, Texas - slides

EPA Science Inventory

While sewer renewal technologies currently being used for the repair, replacement and/or rehabilitation of deteriorating wastewater collection systems are generally effective, there is still room for improvement of existing technologies and for the development of new technologies...

78 FR 18629 - Notice of Lodging of Proposed Partial Consent Decree Under the Clean Water Act

Federal Register 2010, 2011, 2012, 2013, 2014

2013-03-27

... sewer system, perform initial work over the next four years to address sewer overflows, develop a..., DC 20044- 7611. Please enclose a check or money order for $84.50 (25 cents per page reproduction cost...

Sewer deterioration modeling with condition data lacking historical records.

PubMed

Egger, C; Scheidegger, A; Reichert, P; Maurer, M

2013-11-01

Accurate predictions of future conditions of sewer systems are needed for efficient rehabilitation planning. For this purpose, a range of sewer deterioration models has been proposed which can be improved by calibration with observed sewer condition data. However, if datasets lack historical records, calibration requires a combination of deterioration and sewer rehabilitation models, as the current state of the sewer network reflects the combined effect of both processes. Otherwise, physical sewer lifespans are overestimated as pipes in poor condition that were rehabilitated are no longer represented in the dataset. We therefore propose the combination of a sewer deterioration model with a simple rehabilitation model which can be calibrated with datasets lacking historical information. We use Bayesian inference for parameter estimation due to the limited information content of the data and limited identifiability of the model parameters. A sensitivity analysis gives an insight into the model's robustness against the uncertainty of the prior. The analysis reveals that the model results are principally sensitive to the means of the priors of specific model parameters, which should therefore be elicited with care. The importance sampling technique applied for the sensitivity analysis permitted efficient implementation for regional sensitivity analysis with reasonable computational outlay. Application of the combined model with both simulated and real data shows that it effectively compensates for the bias induced by a lack of historical data. Thus, the novel approach makes it possible to calibrate sewer pipe deterioration models even when historical condition records are lacking. Since at least some prior knowledge of the model parameters is available, the strength of Bayesian inference is particularly evident in the case of small datasets. Copyright © 2013 Elsevier Ltd. All rights reserved.

The use of multiple tracers to evaluate the impact of sewered and non-sewered development on coastal water quality in a rural area of Florida.

PubMed

Meeroff, Daniel E; Bloetscher, Frederick; Long, Sharon C; Bocca, Thais

2014-05-01

When onsite wastewater treatment and disposal systems (OSTDS) are not sited appropriately or installed properly, wastewater constituents can be a source of adverse environmental impacts to soil and groundwater, which can lead to potential public health risks. A paired monitoring design developed to compare water quality in sewered and non-sewered areas is presented here. It is suggested as a possible monitoring scheme for assessing the impact of sewer installation projects. As such, two sets of single-family, rural residential Florida neighborhoods were evaluated over a two-year period to gain insight into the effects of small-community use of OSTDS on coastal water quality. One set of two neighborhoods were connected to the sanitary sewer network and the other set of two were served exclusively by OSTDS. Water quality sampling was conducted at the paired sites during seasonal high water table (SHWT) and seasonal low water table (SLWT) events. Measured surface water quality during the SHWT showed indications of environmental impacts from OSTDS in terms of nutrients, microbial pathogen indicators, and other water quality measures, such as turbidity and conductivity. However, during the SLWT events, no obvious impacts attributable to OSTDS were detected. The water quality results indicate that OSTDS impacts may be measureable in rural areas. Other factors, such as microbial indicator survival and regrowth potential, may confound the understanding of water quality impacts of sewer projects. For example, the microbial indicators Escherichia coli and enterococci were found to persist over time and therefore did not always represent true comparisons of OSTDS and sewered areas between seasons. The timeframe for evaluating the effects of sewer projects may be longer than anticipated because of this survival and regrowth phenomenon.

76 FR 51397 - Notice of Lodging of Consent Decree Under the Clean Water Act

Federal Register 2010, 2011, 2012, 2013, 2014

2011-08-18

... the Clean Water Act, 33 U.S.C. 1251 et seq., at its sewer system and water pollution control plant. To... extensive work to its sewer system and water pollution control plant to eliminate violations of the Clean... DEPARTMENT OF JUSTICE Notice of Lodging of Consent Decree Under the Clean Water Act Notice is...

Fault detection on a sewer network by a combination of a Kalman filter and a binary sequential probability ratio test

NASA Astrophysics Data System (ADS)

Piatyszek, E.; Voignier, P.; Graillot, D.

2000-05-01

One of the aims of sewer networks is the protection of population against floods and the reduction of pollution rejected to the receiving water during rainy events. To meet these goals, managers have to equip the sewer networks with and to set up real-time control systems. Unfortunately, a component fault (leading to intolerable behaviour of the system) or sensor fault (deteriorating the process view and disturbing the local automatism) makes the sewer network supervision delicate. In order to ensure an adequate flow management during rainy events it is essential to set up procedures capable of detecting and diagnosing these anomalies. This article introduces a real-time fault detection method, applicable to sewer networks, for the follow-up of rainy events. This method consists in comparing the sensor response with a forecast of this response. This forecast is provided by a model and more precisely by a state estimator: a Kalman filter. This Kalman filter provides not only a flow estimate but also an entity called 'innovation'. In order to detect abnormal operations within the network, this innovation is analysed with the binary sequential probability ratio test of Wald. Moreover, by crossing available information on several nodes of the network, a diagnosis of the detected anomalies is carried out. This method provided encouraging results during the analysis of several rains, on the sewer network of Seine-Saint-Denis County, France.

A risk-based approach to sanitary sewer pipe asset management.

PubMed

Baah, Kelly; Dubey, Brajesh; Harvey, Richard; McBean, Edward

2015-02-01

Wastewater collection systems are an important component of proper management of wastewater to prevent environmental and human health implications from mismanagement of anthropogenic waste. Due to aging and inadequate asset management practices, the wastewater collection assets of many cities around the globe are in a state of rapid decline and in need of urgent attention. Risk management is a tool which can help prioritize resources to better manage and rehabilitate wastewater collection systems. In this study, a risk matrix and a weighted sum multi-criteria decision-matrix are used to assess the consequence and risk of sewer pipe failure for a mid-sized city, using ArcGIS. The methodology shows that six percent of the uninspected sewer pipe assets of the case study have a high consequence of failure while four percent of the assets have a high risk of failure and hence provide priorities for inspection. A map incorporating risk of sewer pipe failure and consequence is developed to facilitate future planning, rehabilitation and maintenance programs. The consequence of failure assessment also includes a novel failure impact factor which captures the effect of structurally defective stormwater pipes on the failure assessment. The methodology recommended in this study can serve as a basis for future planning and decision making and has the potential to be universally applied by municipal sewer pipe asset managers globally to effectively manage the sanitary sewer pipe infrastructure within their jurisdiction. Copyright © 2014 Elsevier B.V. All rights reserved.

APPROACH TO "FURTHER-REASONABLE-PROGRESS" TO ATTAIN WATER QUALITY STANDARDS

EPA Science Inventory

Watershed managers in urban areas in the US are pursuing optimum strategies or plans for managing wastewater treatment plants, stormwater systems, sanitary sewer overflows (SSO) and combined sewer overflows (CSO). Often these strategies are based on an iterative process or a "fur...

APPROACH TO "FURTHER-REASONABLE-PROGRESS" TO ATTAIN WATER QUALITY STANDARDS

EPA Science Inventory

Watershed managers in urban areas in the US are pursuing optimum strategies or plans for managing wastewater treatment plants, stormwater systems, sanitary sewer overflows (SSO) and combined sewer overflows (CSO). Often thes strategies are based on an iterative process or a "furt...

Enforcement to Address Sewer Overflows | Eliminating ...

EPA Pesticide Factsheets

2017-04-10

EPA's compliance goal is to eliminate sanitary sewer overflows (SSOs) from municipal collection systems and to ensure that wastewater is being conveyed to treatment plants in accordance with the requirements of the Clean Water Act. To eliminate SSOs, EPA uses a mix of compliance and enforcement tools.

LAND USE AND SEASONAL EFFECTS ON URBAN STORMWATER RUNOFF MICROORGANISM CONCENTRATIONS

EPA Science Inventory

Stormwater samples collected from storm sewers draining small municipal separate storm sewer systems shown to be free of cross connections within an urban watershed dominated by a single land use were analyzed for pathogens (Pseudomonas aeruginosa and Staphylococcus aureus) and i...

EFFECTS OF LAND USE AND SEASON ON MICROORGANISM CONCENTRATIONS IN URBAN STORMWATER RUNOFF

EPA Science Inventory

This study investigated differences in pathogen and indicator organism concentrations in stormwater runoff between different urban land uses and seasons. Stormwater samples collected from storm sewers draining small municipal separate storm sewer systems shown to be free of cros...

MODELS TO ESTIMATE VOLATILE ORGANIC HAZARDOUS AIR POLLUTANT EMISSIONS FROM MUNICIPAL SEWER SYSTEMS

EPA Science Inventory

Emissions from municipal sewers are usually omitted from hazardous air pollutant (HAP) emission inventories. This omission may result from a lack of appreciation for the potential emission impact and/or from inadequate emission estimation procedures. This paper presents an analys...

A microcomputer model for simulating pressurized flow in a storm sewer system : interim report.

DOT National Transportation Integrated Search

1988-01-01

A study is being conducted on the development of a microcomputer model for simulating storm sewer flow under surcharged or pressurized conditions. Several existing models, including the EPA Storm Water Management Hodel (SYMM) and the Illinois Urban D...

Effects of sanitary sewers on ground-water levels and streams in Nassau and Suffolk Counties, New York; Part 3, development and application of southern Nassau County model

USGS Publications Warehouse

Reilly, T.E.; Buxton, H.T.

1985-01-01

By 1990, sanitary sewers in Nassau County Sewage Disposal Districts 2 and 3 and Suffolk County Southwest Sewer District will discharge to the ocean 140 cu ft of water per second that would otherwise be returned to the groundwater system through septic tanks and similar systems. To evaluate the effects of this loss on groundwater levels and streamflow, the U.S. Geological Survey developed a groundwater flow model that couples a fine-scale subregional model to a regional model of a larger scale. The regional model generates flux boundary conditions for the subregional model, and the subregional model provides detail in the area of concern. Results indicate that the water table will decline by as much as 90% from conditions in the early 1970's. This report is one of a three-part series describing the predicted hydrologic effects of sewers in southern Nassau and southwestern Suffolk Counties. (USGS)

Fuzzy neural network for flow estimation in sewer systems during wet weather.

PubMed

Shen, Jun; Shen, Wei; Chang, Jian; Gong, Ning

2006-02-01

Estimation of the water flow from rainfall intensity during storm events is important in hydrology, sewer system control, and environmental protection. The runoff-producing behavior of a sewer system changes from one storm event to another because rainfall loss depends not only on rainfall intensities, but also on the state of the soil and vegetation, the general condition of the climate, and so on. As such, it would be difficult to obtain a precise flowrate estimation without sufficient a priori knowledge of these factors. To establish a model for flow estimation, one can also use statistical methods, such as the neural network STORMNET, software developed at Lyonnaise des Eaux, France, analyzing the relation between rainfall intensity and flowrate data of the known storm events registered in the past for a given sewer system. In this study, the authors propose a fuzzy neural network to estimate the flowrate from rainfall intensity. The fuzzy neural network combines four STORMNETs and fuzzy deduction to better estimate the flowrates. This study's system for flow estimation can be calibrated automatically by using known storm events; no data regarding the physical characteristics of the drainage basins are required. Compared with the neural network STORMNET, this method reduces the mean square error of the flow estimates by approximately 20%. Experimental results are reported herein.

Output-feedback control of combined sewer networks through receding horizon control with moving horizon estimation

NASA Astrophysics Data System (ADS)

Joseph-Duran, Bernat; Ocampo-Martinez, Carlos; Cembrano, Gabriela

2015-10-01

An output-feedback control strategy for pollution mitigation in combined sewer networks is presented. The proposed strategy provides means to apply model-based predictive control to large-scale sewer networks, in-spite of the lack of measurements at most of the network sewers. In previous works, the authors presented a hybrid linear control-oriented model for sewer networks together with the formulation of Optimal Control Problems (OCP) and State Estimation Problems (SEP). By iteratively solving these problems, preliminary Receding Horizon Control with Moving Horizon Estimation (RHC/MHE) results, based on flow measurements, were also obtained. In this work, the RHC/MHE algorithm has been extended to take into account both flow and water level measurements and the resulting control loop has been extensively simulated to assess the system performance according different measurement availability scenarios and rain events. All simulations have been carried out using a detailed physically based model of a real case-study network as virtual reality.

Association between Gastrointestinal Illness and Precipitation in Areas Impacted by Combined Sewer Facilities: Analysis of Massachusetts Data, 2003-2007

EPA Science Inventory

Background: Combined sewer systems (CSS) collect rainwater runoff, sewage, and industrial wastewater for transit to treatment facilities. With heavy precipitation, volumes can exceed capacity of treatment facilities, and wastewater discharges directly to receiving waters. These c...

NPDES Permit for NIST Boulder Laboratories Municipal Separate Storm Sewer System in Colorado

EPA Pesticide Factsheets

Under NPDES permit CO-R042002,NIST is authorized to discharge from all municipal separate storm sewer outfalls existing as of the effective date of this permit to receiving waters within the exterior boundaries of the Boulder Laboratories in Boulder, Colo.

A microcomputer model for simulating pressurized flow in a storm sewer system : final report.

DOT National Transportation Integrated Search

1989-01-01

A review was made of several computer programs capable of simulating sewer flows under surcharge or pressurized flow conditions. A modified version of the EXTRAN module of the SYMM model, called PFSM, was developed and attached to the FHYA Pooled Fun...

pH dynamics in sewers and its modeling.

PubMed

Sharma, Keshab; Ganigue, Ramon; Yuan, Zhiguo

2013-10-15

pH variation in sewers has a significant effect on hydrogen sulfide production and emissions, and hence its accurate prediction is critical for the optimization of mitigation strategies. In this study, the nature and dynamics of pH variation in a sewer system is examined. Three sewer systems collecting domestic wastewater were monitored, with pH in all cases showing large diurnal variations. pH in fresh sewage in all three cases had a very similar trend with maximum pH in the range of 8.5-8.7. pH variation in fresh sewage followed the same pattern as the sewage flow rate, suggesting that sewage pH is influenced by household water use. Nitrogen content of the wastewater was found to be the most influential factor causing pH variation in fresh sewage, with the total ammonium concentration variation well correlated with the pH variation. A methodology for predicting pH variation in sewers is developed and calibration protocols proposed. The methodology, which is based on the concept of charge balance, was validated using titration curves and field pH data. Measurement of the total ammonium concentration in fresh sewage was found necessary and adequate for the calibration of the charge balance-based pH model. Copyright © 2013 Elsevier Ltd. All rights reserved.

Public Infrastructure Disparities and the Microbiological and Chemical Safety of Drinking and Surface Water Supplies in a Community Bordering a Landfill

PubMed Central

Heaney, Christopher D.; Wing, Steve; Wilson, Sacoby M.; Campbell, Robert L.; Caldwell, David; Hopkins, Barbara; O’Shea, Shannon; Yeatts, Karin

2015-01-01

The historically African-American Rogers-Eubanks community straddles unincorporated boundaries of two municipalities in Orange County, North Carolina, and predates a regional landfill sited along its border in 1972. Community members from the Rogers-Eubanks Neighborhood Association (RENA), concerned about deterioration of private wells and septic systems and a lack of public drinking water and sewer services, implemented a community-driven research partnership with university scientists and community-based organizations to investigate water and sewer infrastructure disparities and the safety of drinking and surface water supplies. RENA drafted memoranda of agreement with partners and trained community monitors to collect data (inventory households, map water and sewer infrastructure, administer household water and sewer infrastructure surveys, and collect drinking and surface water samples). Respondents to the surveys reported pervasive signs of well vulnerability (100%) and septic system failure (68%). Each 100-m increase in distance from the landfill was associated with a 600 most probable number/100 mL decrease in enterococci concentrations in surface water (95% confidence interval = −1106, −93). Pervasive private household water and sewer infrastructure failures and poor water quality were identified in this community bordering a regional landfill, providing evidence of a need for improved water and sanitation services. PMID:23858663

Assessment of pollutant load emission from combined sewer overflows based on the online monitoring.

PubMed

Brzezińska, Agnieszka; Zawilski, Marek; Sakson, Grażyna

2016-09-01

Cities equipped with combined sewer systems discharge during wet weather a lot of pollutants into receiving waters by combined storm overflows (CSOs). According to the Polish legislation, CSOs should be activated no more than ten times per year, but in Lodz, most of the 18 existing CSOs operate much more frequently. To assess the pollutant load emitted by one of the existing CSOs, the sensors for measuring the concentration of total suspended solids (SOLITAX sc) and dissolved chemical oxygen demand (UVAS plus) installed in the overflow chamber as well as two flowmeters placed in the outflow sewer were used. In order to check the data from sensors, laboratory tests of combined wastewater quality were conducted simultaneously. For the analysis of the total pollutant load emitted from the overflow, the raw data was denoised using the Savitzky-Golay method. Comparing the load calculated from the analytical results to online smoothed measurements, negligible differences were found, which confirms the usefulness of applying the sensors in the combined sewer system. Online monitoring of the quantity and quality of wastewater emitted by the combined sewer overflows to water receivers, provides a considerable amount of data very useful for combined sewerage upgrading based on computer modelling, and allows for a significant reduction of laboratory analysis.

Loads of suspended sediment and nutrients from local nonpoint sources to the tidal Potomac River and Estuary, Maryland and Virginia, 1979-81 water years

USGS Publications Warehouse

Hickman, R. Edward

1987-01-01

Loads of suspended sediment, phosphorus, nitrogen, biochemical oxygen demand, and dissolved silica discharged to the tidal Potomac River and Estuary during the !979-81 water years from three local nonpoint sources have been calculated. The loads in rain falling directly upon the tidal water surface and from overflows of the combined sewer system of the District of Columbia were determined from available information. Loads of materials in the streamflow from local watersheds draining directly to the tidal Potomac River and Estuary downstream from Chain Bridge in Washington, D.C., were calculated from samples of streamflow leaving five monitored watersheds. Average annual yields of substances leaving three urban watersheds (Rock Creek and the Northwest and Northeast Branches of the Anacostia River) and the rural Saint Clements Creek watershed were calculated either by developing relationships between concentration and streamflow or by using the mean of measured concentrations. Yields calculated for the 1979-81 water years are up to 2.3 times period-of-record yields because of greater than average streamflow and stormflow during this 3-year period. Period-of-record yields of suspended sediment from the three urban watersheds and the Saint Clements Creek watershed do not agree with yields reported by other studies. The yields from the urban watersheds are 17 to 51 percent of yields calculated using sediment-concentration data collected during the 1960-62 water years. Previous studies suggest that this decrease is at least partly due to the imposition of effective sediment controls at construction sites and to the construction of two multipurpose reservoirs. The yield calculated for the rural Saint Clements Creek watershed is at least twice the yields calculated for other rural watersheds, a result that may be due to most of the samples of this stream being taken during the summer of the 1981 water year, a very dry period. Loads discharged from all local tributary watersheds to the tidal Potomac River and Estuary during the 1979-81 water years were calculated by applying to the unsampled watersheds the yields determined for the monitored watersheds. The resulting loads are 2.7 million megagrams of suspended sedi- ment, 3,100 megagrams of phosphorus, 14,000 megagrams of nitrogen, 74,000 megagrams of ultimate biochemical oxygen demand, and 68,000 megagrams of dissolved silica. The value for the load of sediment is probably an overestimate because the sediment yield calculated for the Saint Clements Creek watershed does not appear to be representative of rural watersheds. Summed, the loads discharged from all local nonpoint sources (local tributary watersheds, rainfall, and combined sewer overflows) to the tidal Potomac River and Estuary during the 1979-81 water years are 2.7 million megagrams of suspended sediment, 3,300 megagrams of phosphorus, 18,000 megagrams of nitrogen, 78,000 megagrams of ultimate biochemical oxygen demand, and 69,000 megagrams of dissolved silica. These loads accounted for 17 to 38 percent of the loads discharged by major sources during this period.

Final Environmental Assessment for Proposed Additional Development, Testing Use, and Associated Training at the Technical Evaluation Assessment Monitor Site (TEAMS) at Kirtland Air Force Base, New Mexico

DTIC Science & Technology

2015-02-01

supply, sanitary sewage/wastewater, storm water handling, and communications systems. Solid waste TEAMS Final Environmental Assessment Kirtland...appropriately sanitized prior to being placed back into service. This will ensure safety of the water system. Sanitary Sewer/Wastewater System. Kirtland...AFB does not have its own sewage treatment plant. Instead, the sanitary sewer system of Kirtland AFB transports wastewater to the city of

Sewage Monitors

NASA Technical Reports Server (NTRS)

1987-01-01

Every U.S. municipality must determine how much waste water it is processing and more importantly, how much is going unprocessed into lakes and streams either because of leaks in the sewer system or because the city's sewage facilities were getting more sewer flow than they were designed to handle. ADS Environmental Services, Inc.'s development of the Quadrascan Flow Monitoring System met the need for an accurate method of data collection. The system consists of a series of monitoring sensors and microcomputers that continually measure water depth at particular sewer locations and report their findings to a central computer. This provides precise information to city managers on overall flow, flow in any section of the city, location and severity of leaks and warnings of potential overload. The core technology has been expanded upon in terms of both technical improvements, and functionality for new applications, including event alarming and control for critical collection system management problems.

Effects of real time control of sewer systems on treatment plant performance and receiving water quality.

PubMed

Frehmann, T; Niemann, A; Ustohal, P; Geiger, W F

2002-01-01

Four individual mathematical submodels simulating different subsystems of urban drainage were intercoupled to an integral model. The submodels (for surface runoff, flow in sewer system, wastewater treatment plant and receiving water) were calibrated on the basis of field data measured in an existing urban catchment investigation. Three different strategies for controlling the discharge in the sewer network were defined and implemented in the integral model. The impact of these control measures was quantified by representative immission state-parameters of the receiving water. The results reveal that the effect of a control measure may be ambivalent, depending on the referred component of a complex drainage system. Furthermore, it is demonstrated that the drainage system in the catchment investigation can be considerably optimised towards environmental protection and operation efficiency if an appropriate real time control on the integral scale is applied.

Fecal-indicator bacteria in streams alonga gradient of residential development

USGS Publications Warehouse

Frenzel, Steven A.; Couvillion, Charles S.

2002-01-01

Fecal-indicator bacteria were sampled at 14 stream sites in Anchorage, Alaska, USA, as part of a study to determine the effects of urbanization on water quality. Population density in the subbasins sampled ranged from zero to 1,750 persons per square kilometer. Higher concentrations of fecal-coliform, E. coli, and enterococci bacteria were measured at the most urbanized sites. Although fecal-indicator bacteria concentrations were higher in summer than in winter, seasonal differences in bacteria concentrations generally were not significant. Areas served by sewer systems had significantly higher fecal-indicator bacteria concentrations than did areas served by septic systems. The areas served by sewer systems also had storm drains that discharged directly to the streams, whereas storm sewers were not present in the areas served by septic systems. Fecal-indicator bacteria concentrations were highly variable over a two-day period of stable streamflow, which may have implications for testing of compliance to water-quality standards.

Risk assessment of sewer condition using artificial intelligence tools: application to the SANEST sewer system.

PubMed

Sousa, V; Matos, J P; Almeida, N; Saldanha Matos, J

2014-01-01

Operation, maintenance and rehabilitation comprise the main concerns of wastewater infrastructure asset management. Given the nature of the service provided by a wastewater system and the characteristics of the supporting infrastructure, technical issues are relevant to support asset management decisions. In particular, in densely urbanized areas served by large, complex and aging sewer networks, the sustainability of the infrastructures largely depends on the implementation of an efficient asset management system. The efficiency of such a system may be enhanced with technical decision support tools. This paper describes the role of artificial intelligence tools such as artificial neural networks and support vector machines for assisting the planning of operation and maintenance activities of wastewater infrastructures. A case study of the application of this type of tool to the wastewater infrastructures of Sistema de Saneamento da Costa do Estoril is presented.

Hydrologic and Water-Quality Characterization and Modeling of the Onondaga Lake Basin, Onondaga County, New York

USGS Publications Warehouse

Coon, William F.; Reddy, James E.

2008-01-01

Onondaga Lake in Onondaga County, New York, has been identified as one of the Nation?s most contaminated lakes as a result of industrial and sanitary-sewer discharges and stormwater nonpoint sources, and has received priority cleanup status under the national Water Resources Development Act of 1990. A basin-scale precipitation-runoff model of the Onondaga Lake basin was identified as a desirable water-resources management tool to better understand the processes responsible for the generation of loads of sediment and nutrients that are transported to Onondaga Lake. During 2003?07, the U.S. Geological Survey (USGS) developed a model based on the computer program, Hydrological Simulation Program?FORTRAN (HSPF), which simulated overland flow to, and streamflow in, the major tributaries of Onondaga Lake, and loads of sediment, phosphorus, and nitrogen transported to the lake. The simulation period extends from October 1997 through September 2003. The Onondaga Lake basin was divided into 107 subbasins and within these subbasins, the land area was apportioned among 19 pervious and impervious land types on the basis of land use and land cover, hydrologic soil group (HSG), and aspect. Precipitation data were available from three sources as input to the model. The model simulated streamflow, water temperature, concentrations of dissolved oxygen, and concentrations and loads of sediment, orthophosphate, total phosphorus, nitrate, ammonia, and organic nitrogen in the four major tributaries to Onondaga Lake?Onondaga Creek, Harbor Brook, Ley Creek, and Ninemile Creek. Simulated flows were calibrated to data from nine USGS streamflow-monitoring sites; simulated nutrient concentrations and loads were calibrated to data collected at six of the nine streamflow-monitoring sites. Water-quality samples were collected, processed, and analyzed by personnel from the Onondaga County Department of Water Environment Protection. Several time series of flow, and sediment and nutrient loads were generated for known sources of these constituents, including the Tully Valley mudboils (flow and sediment), Otisco Lake (flow and nutrients), the Marcellus wastewater-treatment plant (flow and nutrients), and springs from carbonate bedrock (flow). Runoff from the impervious sewered areas of the City of Syracuse was adjusted for the quantity that was treatable at the county wastewater-treatment plant; the excess flows were routed to nearby streams through combined-sanitary-and-storm-sewer overflows. The mitigative effects that the Onondaga Reservoir and Otisco Lake were presumed to have on loads of sediment and particulate constituents were simulated by adjustment of parameter values that controlled sediment settling rates, deposition, and scour in the reservoir and lake. Graphical representations of observed and simulated data, and relevant statistics, were compared to assess model performance. Simulated daily and monthly streamflows were rated ?very good? (within 10 percent of observed flows) at all calibration sites, except Onondaga Creek at Cardiff, which was rated ?fair? (10?15 percent difference). Simulations of monthly average water temperatures were rated ?very good? (within 7 percent of observed temperatures) at all sites. No observed data were available by which to directly assess the model?s simulation of suspended sediment loads. Available measured total suspended solids data provided an indirect means of comparison but, not surprisingly, yielded only ?fair? to ?poor? ratings (greater than 30 percent difference) for simulated monthly sediment loads at half the water-quality calibration sites. Simulations of monthly orthophosphate loads ranged from ?very good? (within 15 percent of measured loads) at three sites to ?poor? (greater than 35 percent difference) at one site; simulations of ammonia nitrogen loads ranged from ?very good? at one site to ?fair? (25?35 percent difference) at two sites. Simulations of monthly total phosphorus, nitrate, and or

Sedimentation Survey of Lago Toa Vaca, Puerto Rico, June-July 2002

USGS Publications Warehouse

Soler-López, Luis R.

2004-01-01

The Lago Toa Vaca dam is located in the municipality of Villalba in southern Puerto Rico, and is owned and operated by the Puerto Rico Aqueduct and Sewer Authority. Construction was completed in 1972 as the first phase of a multi-purpose project that contemplated four possible diversions from other basins to mitigate the rapid storage capacity loss of Lago Guayabal, located immediately downstream of the Toa Vaca dam. The latter phases of the intra-basin diversions were cancelled, and currently, the reservoir receives runoff from only 56.8 square kilometers of its drainage area. Lago Toa Vaca reservoir when constructed was to be used for irrigation of croplands in the southern coastal plain. The reservoir had an original storage capacity of 68.94 million cubic meters. Sedimentation has reduced the storage capacity by only 7 percent between 1972 and 2002 to 64.08 million cubic meters. This represents a long-term sedimentation rate of about 162,000 cubic meters per year. Based on the 2002 sedimentation survey, Lago Toa Vaca has a sediment trapping efficiency of about 98 percent and a drainage area-normalized sedimentation rate of about 3,086 cubic meters per square kilometer per year between 1972 and 2002. At the current long-term sedimentation rate the reservoir would lose its storage capacity by the year 2400.

COLLECTION SYSTEM SOLIDS CONTROL: OVERVIEW OF AN EPA WET-WEATHER FLOW RESEARCH PROGRAM

EPA Science Inventory

This paper presents an historical overview of the sewer-solids control projects conducted by the Wet-Weather Flow Research Program of the US EPA. Research includes studies of the causes of sewer-solids deposition and development/evaluation of control methods that can prevent sewe...

Measuring Flow Reductions in a Combined Sewer System Using Green Infrastructure

EPA Science Inventory

A green infrastructure (GI) design approach was used in CSO Basin #130, a 17-acre sewershed in the Butchertown section of Louisville, Kentucky, to reduce combined sewer overflows (CSOs). For the design year, the modeled design was expected to reduce the CSO frequency from 34 to ...

Green Infrastructure in the Mix to Reduce District of Columbia Sewer Overflows

EPA Pesticide Factsheets

District of Columbia's Long Term Control Plan to keep sewage out of the city’s rivers is being modified to include a substantial greening component for the first time, making it a dominant feature of 2 of the 3 drainage areas of the combined sewer system.

RATES OF GASTROINTESTINAL ILLNESS AMONG AREAS IMPACTED BY COMBINED SEWER FACILITIES: ANALYSIS OF MASSACHUSETTS DATA, 2003-2007

EPA Science Inventory

Previous studies have reported a temporal association between heavy rainfall and gastrointestinal infection (GI). Combined sewer systems (CSSs), which are present in many urban areas in the US, were designed to collect rainwater runoff, domestic sewage, and industrial wastewater ...

Statistically based sustainable re-design of stormwater overflow control systems in urban catchments

NASA Astrophysics Data System (ADS)

Ganora, Daniele; Isacco, Silvia; Claps, Pierluigi

2017-04-01

Control and reduction of pollution from stormwater overflow is a major concern for municipalities to manage the quality of the receiving water bodies according to the Framework Water Directive 2000/60/CE. In this regard, assessment studies of the potential pollution load from sewer networks recognize the need for adaptation and upgrade of existing drainage systems, which can be achieved with either traditional water works (detention tanks, increase of wastewater treatment plant capacity, etc.) or even Nature-based solutions (constructed wetlands, restored floodplains, etc.) sometimes used in combination. Nature-based solutions are recently receiving consistent attentions as they are able to enhance urban and degraded environments being, in the same time, more resilient and adaptable to climatic and anthropic changes than most traditional engineering works. On the other hand, restoration of the urban environment using natural absorbing surfaces requires diffuse interventions, high costs and a considerable amount of time. In this work we investigate how simple, economically-sustainable and quick solutions to the problem at hand can be addressed by changes in the management rules when pumping stations play a role in sewer systems. In particular, we provide a statistically-based framework to be used in the calibration of the management rules, facing improved quality of overflows from sewer systems. Typical pumping rules favor a massive delivery of stormwater volumes to the wastewater treatment plans, requiring large storage tanks in the sewer network, heavy pumping power and reducing the efficiency of the treatment plant due to pollutant dilution. In this study we show that it is possible to optimize the pumping rule in order to reduce pumped volumes to the plant (thus saving energy), while simultaneously keeping high pollutant concentration. On the other hand, larger low-concentration overflow volumes are released outside the sewer network with respect to the standard pumping rules. Such released volumes could be efficiently processed by nature-based solutions, like for instance constructed wetlands, to reduce the final pollutant impact on the environment. The proposed procedure is based on the previous knowledge of the precipitation forcing and of a quantity/quality model of the sewer network. The method provides marginal and joint probability distributions of water volumes and pollutant concentration (or mass) delivered toward the wastewater treatment plant and the Nature-based system, with the aim of supporting a more efficient design of the whole sewer system. A practical example of application is provided for illustrative purposes.

Assessment on inflow and infiltration in sewerage systems of Kuantan, Pahang.

PubMed

Yap, Hiew Thong; Ngien, Su Kong

2017-12-01

Inflow and infiltration are important aspects of sewerage systems that need to be considered during the design stage and constantly monitored once the sewerage system is in operation. The aim of this research is to analyse the relationship of rainfall as well as inflow infiltration with sewage flow patterns through data collected from fieldwork. Three sewer pipelines were selected at the residential areas of Taman Lepar Hilir Saujana, Bandar Putra and Kota Sas for data collection. Sewage flow data were collected in terms of flowrate, velocity and depth of flow using flowmeters with ultrasonic sensors that utilize the continuous Doppler effect in the sewer pipelines, while rainfall intensity data were collected using rain gauges installed at the study locations. Based on the result, the average infiltration rates of Q peak and Q ave for the locations were 17% and 21%, which exceeded the respective values of 5% and 10% stated in Hammer and Hammer. The flowrate of wastewater in the sewer pipelines was found to be directly proportional to rainfall. These findings indicate that the sewer pipelines in the study areas may have been affected by capacity reduction, whereas the sewerage treatment plants receiving the wastewater influent may have been overloaded.

Hydrogeology and groundwater quality at monitoring wells installed for the Tunnel and Reservoir Plan System and nearby water-supply wells, Cook County, Illinois, 1995–2013

USGS Publications Warehouse

Kay, Robert T.

2016-04-04

Groundwater-quality data collected from 1995 through 2013 from 106 monitoring wells open to the base of the Silurian aquifer surrounding the Tunnel and Reservoir Plan (TARP) System in Cook County, Illinois, were analyzed by the U.S. Geological Survey, in cooperation with the Metropolitan Water Reclamation District of Greater Chicago, to assess the efficacy of the monitoring network and the effects of water movement from the tunnel system to the surrounding aquifer. Groundwater from the Silurian aquifer typically drains to the tunnel system so that analyte concentrations in most of the samples from most of the monitoring wells primarily reflect the concentration of the analyte in the nearby Silurian aquifer. Water quality in the Silurian aquifer is spatially variable because of a variety of natural and non-TARP anthropogenic processes. Therefore, the trends in analyte values at a given well from 1995 through 2013 are primarily a reflection of the spatial variation in the value of the analyte in groundwater within that part of the Silurian aquifer draining to the tunnels. Intermittent drainage of combined sewer flow from the tunnel system to the Silurian aquifer when flow in the tunnel systemis greater than 80 million gallons per day may affect water quality in some nearby monitoring wells. Intermittent drainage of combined sewer flow from the tunnel system to the Silurian aquifer appears to affect the values of electrical conductivity, hardness, sulfate, chloride, dissolved organic carbon, ammonia, and fecal coliform in samples from many wells but typically during less than 5 percent of the sampling events. Drainage of combined sewer flow into the aquifer is most prevalent in the downstream parts of the tunnel systems because of the hydraulic pressures elevated above background values and long residence time of combined sewer flow in those areas. Elevated values of the analytes emplaced during intermittent migration of combined sewer flow into the Silurian aquifer decrease through time as water from the aquifer drains back into the tunnels in response to typical hydraulic conditions. Of the analytes sampled, fecal coliform provides the clearest indication of the location and timing of combined sewer flow into the Silurian aquifer surrounding the tunnel system.

Comparison of different synthetic 5-min rainfall time series on the results of rainfall runoff simulations in urban drainage modelling

NASA Astrophysics Data System (ADS)

Krämer, Stefan; Rohde, Sophia; Schröder, Kai; Belli, Aslan; Maßmann, Stefanie; Schönfeld, Martin; Henkel, Erik; Fuchs, Lothar

2015-04-01

The design of urban drainage systems with numerical simulation models requires long, continuous rainfall time series with high temporal resolution. However, suitable observed time series are rare. As a result, usual design concepts often use uncertain or unsuitable rainfall data, which renders them uneconomic or unsustainable. An expedient alternative to observed data is the use of long, synthetic rainfall time series as input for the simulation models. Within the project SYNOPSE, several different methods to generate synthetic rainfall data as input for urban drainage modelling are advanced, tested, and compared. Synthetic rainfall time series of three different precipitation model approaches, - one parametric stochastic model (alternating renewal approach), one non-parametric stochastic model (resampling approach), one downscaling approach from a regional climate model-, are provided for three catchments with different sewer system characteristics in different climate regions in Germany: - Hamburg (northern Germany): maritime climate, mean annual rainfall: 770 mm; combined sewer system length: 1.729 km (City center of Hamburg), storm water sewer system length (Hamburg Harburg): 168 km - Brunswick (Lower Saxony, northern Germany): transitional climate from maritime to continental, mean annual rainfall: 618 mm; sewer system length: 278 km, connected impervious area: 379 ha, height difference: 27 m - Friburg in Brisgau (southern Germany): Central European transitional climate, mean annual rainfall: 908 mm; sewer system length: 794 km, connected impervious area: 1 546 ha, height difference 284 m Hydrodynamic models are set up for each catchment to simulate rainfall runoff processes in the sewer systems. Long term event time series are extracted from the - three different synthetic rainfall time series (comprising up to 600 years continuous rainfall) provided for each catchment and - observed gauge rainfall (reference rainfall) according national hydraulic design standards. The synthetic and reference long term event time series are used as rainfall input for the hydrodynamic sewer models. For comparison of the synthetic rainfall time series against the reference rainfall and against each other the number of - surcharged manholes, - surcharges per manhole, - and the average surcharge volume per manhole are applied as hydraulic performance criteria. The results are discussed and assessed to answer the following questions: - Are the synthetic rainfall approaches suitable to generate high resolution rainfall series and do they produce, - in combination with numerical rainfall runoff models - valid results for design of urban drainage systems? - What are the bounds of uncertainty in the runoff results depending on the synthetic rainfall model and on the climate region? The work is carried out within the SYNOPSE project, funded by the German Federal Ministry of Education and Research (BMBF).

Final Environmental Assessment (EA) for Replacement of the Wastewater Lift Station (Building 510)

DTIC Science & Technology

2013-03-01

ensure that wastewater from FEW continues to be safely and efficiently moved to the City of Cheyenne sanitary sewer system. The lift station is...from four to six inches. The subsoil is primarily alluvial clay that extends from a depth of approximately 6 to 36 inches. 8.4. Air Quality. Under...Disposal 8.6.1. Sanitary Sewer System A National Pollutant Discharge Elimination System (NPDES) permit issued by the WYDEQ is in place to allow discharge

Environmental Assessment (EA) for Replacement of the Wastewater Lift Station (Building 510)

DTIC Science & Technology

2013-04-13

ensure that wastewater from FEW continues to be safely and efficiently moved to the City of Cheyenne sanitary sewer system. The lift station is...from four to six inches. The subsoil is primarily alluvial clay that extends from a depth of approximately 6 to 36 inches. 8.4. Air Quality. Under...Disposal 8.6.1. Sanitary Sewer System A National Pollutant Discharge Elimination System (NPDES) permit issued by the WYDEQ is in place to allow discharge

Vapor Intrusion from Entrapped NAPL Sources and Groundwater Plumes: Process Understanding and Improved Modeling Tools for Pathway Assessment

DTIC Science & Technology

2014-07-01

into a building ....149 Figure 5.52: Effect of infiltration at 1 mm/hr for 24 hours on vapor signals in sandy clay loam scenario...shown above, there will also likely be large diameter sanitary sewers running the length of each street. Each house on the street will have a sewer...permeability, a discontinuous clay layer system, and a system with scattered obstacles (e.g. utilities). The layered systems indicated that the sequence of

A hydrogeological conceptual approach to study urban groundwater flow in Bucharest city, Romania

NASA Astrophysics Data System (ADS)

Boukhemacha, Mohamed Amine; Gogu, Constantin Radu; Serpescu, Irina; Gaitanaru, Dragos; Bica, Ioan

2015-05-01

Management of groundwater systems in urban areas is necessary and can be reliably performed by means of mathematical modeling combined with geospatial analysis. A conceptual approach for the study of urban hydrogeological systems is presented. The proposed approach is based on the features of Bucharest city (Romania) and can be adapted to other urban areas showing similar characteristics. It takes into account the interaction between groundwater and significant urban infrastructure elements that can be encountered in modern cities such as subway tunnels and water-supply networks, and gives special attention to the sewer system. In this respect, an adaptation of the leakage factor approach is proposed, which uses a sewer-system zoning function related to the conduits' location in the aquifer system and a sewer-conduits classification function related to their structural and/or hydraulic properties. The approach was used to elaborate a single-layered steady state groundwater flow model for a pilot zone of Bucharest city.

NORTH PORTAL-SANITARY SEWER CALCULATION-SHOP BUILDING #5006

DOE Office of Scientific and Technical Information (OSTI.GOV)

S. Blackstone

1996-01-24

The purpose of this design calculation is to determine the demand on the waste system and to size the sanitary sewer line serving the Shop Building No.5006 in accordance with the Uniform Plumbing Code (Section 4.4.1) and US Department of Energy Order 6430.1A-1540 (Section 4.4.2).

Interim Significant Noncompliance Policy for Clean Water Act Violations Associated with CSOs, SSOs, CAFOs, and Storm Water Point Sources

EPA Pesticide Factsheets

This policy addresses significant noncompliance (SNC) violations associated with combined sewer overflows (CSOs), sanitary sewer overflows (SSOs), concentrated animal feeding operations (CAFOs), and storm water point source discharges covered by the National Pollutant Discharge Elimination System (NPDES) program under the Clean Water Act (CWA).

76 FR 35215 - Notice of EPA Workshop on Sanitary Sewer Overflows and Peak Wet Weather Discharges

Federal Register 2010, 2011, 2012, 2013, 2014

2011-06-16

... draft Peak Flows Policy. The workshop will include a facilitated discussion with representatives of organizations that represent POTWs, state NPDES permitting authorities, and non-for-profit environmental groups... maintained sanitary sewer systems are meant to collect and transport all of the sewage that flows into them...

76 FR 45617 - Notice of Lodging of the Consent Decree Under the Clean Water Act

Federal Register 2010, 2011, 2012, 2013, 2014

2011-07-29

...) violations stemming from its failure to properly operate and maintain its Combined Sewer Collection System..., implement approved operation and maintenance schedules of its sewers, conduct a pump station evaluation, as... from the Consent Decree Library, P.O. Box 7611, U.S. Department of Justice, Washington, DC 20044-7611...

Predictive optimal control of sewer networks using CORAL tool: application to Riera Blanca catchment in Barcelona.

PubMed

Puig, V; Cembrano, G; Romera, J; Quevedo, J; Aznar, B; Ramón, G; Cabot, J

2009-01-01

This paper deals with the global control of the Riera Blanca catchment in the Barcelona sewer network using a predictive optimal control approach. This catchment has been modelled using a conceptual modelling approach based on decomposing the catchments in subcatchments and representing them as virtual tanks. This conceptual modelling approach allows real-time model calibration and control of the sewer network. The global control problem of the Riera Blanca catchment is solved using a optimal/predictive control algorithm. To implement the predictive optimal control of the Riera Blanca catchment, a software tool named CORAL is used. The on-line control is simulated by interfacing CORAL with a high fidelity simulator of sewer networks (MOUSE). CORAL interchanges readings from the limnimeters and gate commands with MOUSE as if it was connected with the real SCADA system. Finally, the global control results obtained using the predictive optimal control are presented and compared against the results obtained using current local control system. The results obtained using the global control are very satisfactory compared to those obtained using the local control.

Variability estimation of urban wastewater biodegradable fractions by respirometry.

PubMed

Lagarde, Fabienne; Tusseau-Vuillemin, Marie-Hélène; Lessard, Paul; Héduit, Alain; Dutrop, François; Mouchel, Jean-Marie

2005-11-01

This paper presents a methodology for assessing the variability of biodegradable chemical oxygen demand (COD) fractions in urban wastewaters. Thirteen raw wastewater samples from combined and separate sewers feeding the same plant were characterised, and two optimisation procedures were applied in order to evaluate the variability in biodegradable fractions and related kinetic parameters. Through an overall optimisation on all the samples, a unique kinetic parameter set was obtained with a three-substrate model including an adsorption stage. This method required powerful numerical treatment, but improved the identifiability problem compared to the usual sample-to-sample optimisation. The results showed that the fractionation of samples collected in the combined sewer was much more variable (standard deviation of 70% of the mean values) than the fractionation of the separate sewer samples, and the slowly biodegradable COD fraction was the most significant fraction (45% of the total COD on average). Because these samples were collected under various rain conditions, the standard deviations obtained here on the combined sewer biodegradable fractions could be used as a first estimation of the variability of this type of sewer system.

Fractal analysis of urban catchments and their representation in semi-distributed models: imperviousness and sewer system

NASA Astrophysics Data System (ADS)

Gires, Auguste; Tchiguirinskaia, Ioulia; Schertzer, Daniel; Ochoa-Rodriguez, Susana; Willems, Patrick; Ichiba, Abdellah; Wang, Lipen; Pina, Rui; Van Assel, Johan; Bruni, Guendalina; Murla Tuyls, Damian; ten Veldhuis, Marie-Claire

2017-04-01

Land use distribution and sewer system geometry exhibit complex scale dependent patterns in urban environment. This scale dependency is even more visible in a rasterized representation where only a unique class is affected to each pixel. Such features are well grasped with fractal tools, which are based scale invariance and intrinsically designed to characterise and quantify the space filled by a geometrical set exhibiting complex and tortuous patterns. Fractal tools have been widely used in hydrology but seldom in the specific context of urban hydrology. In this paper, they are used to analyse surface and sewer data from 10 urban or peri-urban catchments located in 5 European countries in the framework of the NWE Interreg RainGain project (www.raingain.eu). The aim was to characterise urban catchment properties accounting for the complexity and inhomogeneity typical of urban water systems. Sewer system density and imperviousness (roads or buildings), represented in rasterized maps of 2 m x 2 m pixels, were analysed to quantify their fractal dimension, characteristic of scaling invariance. It appears that both sewer density and imperviousness exhibit scale invariant features that can be characterized with the help of fractal dimensions ranging from 1.6 to 2, depending on the catchment. In a given area, consistent results were found for the two geometrical features, yielding a robust and innovative way of quantifying the level of urbanization. The representation of imperviousness in operational semi-distributed hydrological models for these catchments was also investigated by computing fractal dimensions of the geometrical sets made up of the sub-catchments with coefficients of imperviousness greater than a range of thresholds. It enables to quantify how well spatial structures of imperviousness are represented in the urban hydrological models.

Transfer of glyphosate and its degradate AMPA to surface waters through urban sewerage systems.

PubMed

Botta, Fabrizio; Lavison, Gwenaëlle; Couturier, Guillaume; Alliot, Fabrice; Moreau-Guigon, Elodie; Fauchon, Nils; Guery, Bénédicte; Chevreuil, Marc; Blanchoud, Hélène

2009-09-01

A study of glyphosate and aminomethyl phosphonic acid (AMPA) transfer in the Orge watershed (France) was carried out during 2007 and 2008. Water samples were collected in surface water, wastewater sewer, storm sewer and wastewater treatment plant (WWTP). These two molecules appeared to be the most frequently detected ones in the rivers and usually exceeded the European quality standard concentrations of 0.1microg L(-1) for drinking water. The annual glyphosate estimated load was 1.9 kg year(-1) upstream (agricultural zone) and 179.5 kg year(-1) at the catchment outlet (urban zone). This result suggests that the contamination of this basin by glyphosate is essentially from urban origin (road and railway applications). Glyphosate reached surface water prevalently through storm sewer during rainfall event. Maximum concentrations were detected in storm sewer just after a rainfall event (75-90 microg L(-1)). High concentrations of glyphosate in surface water during rainfall events reflected urban runoff impact. AMPA was always detected in the sewerage system. This molecule reached surface water mainly via WWTP effluent and also through storm sewer. Variations in concentrations of AMPA during hydrological episodes were minor compared to glyphosate variations. Our study highlights that AMPA and glyphosate origins in urban area are different. During dry period, detergent degradation seemed to be the major AMPA source in wastewater.

Identification of sewer pipes to be cleaned for reduction of CSO pollutant load.

PubMed

Nagaiwa, Akihiro; Settsu, Katsushi; Nakajima, Fumiyuki; Furumai, Hiroaki

2007-01-01

To reduce the CSO (Combined Sewer Overflow) pollutant discharge, one of the effective options is cleaning of sewer pipes before rainfall events. To maximize the efficiency, identification of pipes to be cleaned is necessary. In this study, we discussed the location of pipe deposit in dry weather in a combined sewer system using a distributed model and investigated the effect of pipe cleaning to reduce the pollutant load from the CSO. First we simulated the dry weather flow in a combined sewer system. The pipe deposit distribution in the network was estimated after 3 days of dry weather period. Several specific pipes with structural defect and upper end pipes tend to have an accumulation of deposit. Wet weather simulations were conducted with and without pipe cleaning in rainfall events with different patterns. The SS loads in CSO with and without the pipe cleaning were compared. The difference in the estimated loads was interpreted as the contribution of wash-off in the cleaned pipe. The effect of pipe cleaning on reduction of the CSO pollutant load was quantitatively evaluated (e.g. the cleaning of one specific pipe could reduce 22% of total CSO load). The CSO simulations containing pipe cleaning options revealed that identification of pipes with accumulated deposit using the distributed model is very useful and informative to evaluate the applicability of pipe cleaning option for CSO pollutant reduction.

Effect of inlet modelling on surface drainage in coupled urban flood simulation

NASA Astrophysics Data System (ADS)

Jang, Jiun-Huei; Chang, Tien-Hao; Chen, Wei-Bo

2018-07-01

For a highly developed urban area with complete drainage systems, flood simulation is necessary for describing the flow dynamics from rainfall, to surface runoff, and to sewer flow. In this study, a coupled flood model based on diffusion wave equations was proposed to simulate one-dimensional sewer flow and two-dimensional overland flow simultaneously. The overland flow model provides details on the rainfall-runoff process to estimate the excess runoff that enters the sewer system through street inlets for sewer flow routing. Three types of inlet modelling are considered in this study, including the manhole-based approach that ignores the street inlets by draining surface water directly into manholes, the inlet-manhole approach that drains surface water into manholes that are each connected to multiple inlets, and the inlet-node approach that drains surface water into sewer nodes that are connected to individual inlets. The simulation results were compared with a high-intensity rainstorm event that occurred in 2015 in Taipei City. In the verification of the maximum flood extent, the two approaches that considered street inlets performed considerably better than that without street inlets. When considering the aforementioned models in terms of temporal flood variation, using manholes as receivers leads to an overall inefficient draining of the surface water either by the manhole-based approach or by the inlet-manhole approach. Using the inlet-node approach is more reasonable than using the inlet-manhole approach because the inlet-node approach greatly reduces the fluctuation of the sewer water level. The inlet-node approach is more efficient in draining surface water by reducing flood volume by 13% compared with the inlet-manhole approach and by 41% compared with the manhole-based approach. The results show that inlet modeling has a strong influence on drainage efficiency in coupled flood simulation.

Selective inspection planning with ageing forecast for sewer types.

PubMed

Baur, R; Herz, R

2002-01-01

Investments in sewer rehabilitation must be based on inspection and evaluation of sewer conditions with respect to the severity of sewer damage and to environmental risks. This paper deals with the problems of forecasting the condition of sewers in a network from a small sample of inspected sewers. Transition functions from one into the next poorer condition class, which were empirically derived from this sample, are used to forecast the condition of sewers. By the same procedure, transition functions were subsequently calibrated for sub-samples of different types of sewers. With these transition functions, the most probable date of entering a critical condition class can be forecast from sewer characteristics, such as material, period of construction, location, use for waste and/or storm water, profile, diameter and gradient. Results are shown for the estimates about the actual condition of the Dresden sewer network and its deterioration in case of doing nothing about it. A procedure is proposed for scheduling the inspection dates for sewers which have not yet been inspected and for those which have been inspected before.

Web Based Decision Support Tools for Selection of Condition ...

EPA Pesticide Factsheets

Abstract: It has been observed that the majority of older sewer laterals made of concrete or terracotta pipe are deteriorating rapidly. Wastewater agencies, typically responsible for maintaining the portion of the sewer lateral located in the public right-of-way, and property owners, typically responsible for the portion of the lateral located within the private property,face the dilemma of whether to replace or rehabilitate deteriorated laterals at significant expense. Deferment of needed rehabilitation translates to increase in the wastewater agency annual operation and maintenance budget and increased risk to the property owner. Sewer lateral deterioration leads to pipe collapse and costly sewer backup. Increase in transmission and treatment costs due to inflow and infiltration (I/I) into the public sewer system is inevitably borne by the ratepayer. [NOTE: The link below connects to a WERF site where the Final Report can be downloaded for free, after registering at the WERF site. For some projects the Executive Summary is available and can be downloaded for free without registering on the WERF site.] A new web portal has been developed that provides wastewater agencies and property owners with up to date information on sewer lateral inspection techniques, repair and rehabilitation methods, as well as relevant legal and financial issues. The site also offers a discussion forum for sharing knowledge and experiences on this topic. The portal is hosted on

Transformation and Sorption of Illicit Drug Biomarkers in Sewer Systems: Understanding the Role of Suspended Solids in Raw Wastewater.

PubMed

Ramin, Pedram; Libonati Brock, Andreas; Polesel, Fabio; Causanilles, Ana; Emke, Erik; de Voogt, Pim; Plósz, Benedek Gy

2016-12-20

Sewer pipelines, although primarily designed for sewage transport, can also be considered as bioreactors. In-sewer processes may lead to significant variations of chemical loadings from source release points to the treatment plant influent. In this study, we assessed in-sewer utilization of growth substrates (primary metabolic processes) and transformation of illicit drug biomarkers (secondary metabolic processes) by suspended biomass. Sixteen drug biomarkers were targeted, including mephedrone, methadone, cocaine, heroin, codeine, and tetrahydrocannabinol (THC) and their major human metabolites. Batch experiments were performed under aerobic and anaerobic conditions using raw wastewater. Abiotic biomarker transformation and partitioning to suspended solids and reactor wall were separately investigated under both redox conditions. A process model was identified by combining and extending the Wastewater Aerobic/anaerobic Transformations in Sewers (WATS) model and Activated Sludge Model for Xenobiotics (ASM-X). Kinetic and stoichiometric model parameters were estimated using experimental data via the Bayesian optimization method DREAM (ZS) . Results suggest that biomarker transformation significantly differs from aerobic to anaerobic conditions, and abiotic conversion is the dominant mechanism for many of the selected substances. Notably, an explicit description of biomass growth during batch experiments was crucial to avoid significant overestimation (up to 385%) of aerobic biotransformation rate constants. Predictions of in-sewer transformation provided here can reduce the uncertainty in the estimation of drug consumption as part of wastewater-based epidemiological studies.

Waste-water characterization survey, Whiteman Air Force Base, Missouri. Final report, 28 Oct-7 Nov 91

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fields, M.K.; Davis, R.P.

1992-08-01

A wastewater characterization survey was conducted by members of the Armstrong Laboratory Occupational and Environmental Health directorate Water Quality Function from 28 Oct 91 - 7 Nov 91 at Whiteman AFB, MO. The purpose of the survey was to identify and characterize the wastewater, determine the appropriateness of present disposal methods, determine the need for routine sampling or monitoring and recommend parameters for wastewater analysis. Results of the sampling showed metals and volatile organic discharge in varying concentrations throughout the base. Recommendations are: (1) evaluation of industrial operations and chemical disposal procedures at designated sites; (2) routine monitoring of themore » discharge from the Hospital and Audiovisual for silver; (3) excavation and sediment disposal at the Transportation Washrack and WWTP Effluent discharge point; (4) collection and analyses of sludge at oil water separators, to include the oil and water side; (5) evaluation of the sanitary sewer system for corrosion and sediment buildup by a mobile Reveal and Seal Unit; (6) background soil sample collection and analyses; and (7) pretreatment of Aqueous Film Forming Foam discharge and notification of the Base Bioenvironmental Engineer, Environmental Coordinator, and WWTP personnel when discharge occurs.« less

Predicting concrete corrosion of sewers using artificial neural network.

PubMed

Jiang, Guangming; Keller, Jurg; Bond, Philip L; Yuan, Zhiguo

2016-04-01

Corrosion is often a major failure mechanism for concrete sewers and under such circumstances the sewer service life is largely determined by the progression of microbially induced concrete corrosion. The modelling of sewer processes has become possible due to the improved understanding of in-sewer transformation. Recent systematic studies about the correlation between the corrosion processes and sewer environment factors should be utilized to improve the prediction capability of service life by sewer models. This paper presents an artificial neural network (ANN)-based approach for modelling the concrete corrosion processes in sewers. The approach included predicting the time for the corrosion to initiate and then predicting the corrosion rate after the initiation period. The ANN model was trained and validated with long-term (4.5 years) corrosion data obtained in laboratory corrosion chambers, and further verified with field measurements in real sewers across Australia. The trained model estimated the corrosion initiation time and corrosion rates very close to those measured in Australian sewers. The ANN model performed better than a multiple regression model also developed on the same dataset. Additionally, the ANN model can serve as a prediction framework for sewer service life, which can be progressively improved and expanded by including corrosion rates measured in different sewer conditions. Furthermore, the proposed methodology holds promise to facilitate the construction of analytical models associated with corrosion processes of concrete sewers. Copyright © 2016 Elsevier Ltd. All rights reserved.

A software-based sensor for combined sewer overflows.

PubMed

Leonhardt, G; Fach, S; Engelhard, C; Kinzel, H; Rauch, W

2012-01-01

A new methodology for online estimation of excess flow from combined sewer overflow (CSO) structures based on simulation models is presented. If sufficient flow and water level data from the sewer system is available, no rainfall data are needed to run the model. An inverse rainfall-runoff model was developed to simulate net rainfall based on flow and water level data. Excess flow at all CSO structures in a catchment can then be simulated with a rainfall-runoff model. The method is applied to a case study and results show that the inverse rainfall-runoff model can be used instead of missing rain gauges. Online operation is ensured by software providing an interface to the SCADA-system of the operator and controlling the model. A water quality model could be included to simulate also pollutant concentrations in the excess flow.

Nowcasting of rainfall and of combined sewage flow in urban drainage systems.

PubMed

Achleitner, Stefan; Fach, Stefan; Einfalt, Thomas; Rauch, Wolfgang

2009-01-01

Nowcasting of rainfall may be used additionally to online rain measurements to optimize the operation of urban drainage systems. Uncertainties quoted for the rain volume are in the range of 5% to 10% mean square error (MSE), where for rain intensities 45% to 75% MSE are noted. For larger forecast periods up to 3 hours, the uncertainties will increase up to some hundred percents. Combined with the growing number of real time control concepts in sewer systems, rainfall forecast is used more and more in urban drainage systems. Therefore it is of interest how the uncertainties influence the final evaluation of a defined objective function. Uncertainty levels associated with the forecast itself are not necessarily transferable to resulting uncertainties in the catchment's flow dynamics. The aim of this paper is to analyse forecasts of rainfall and specific sewer output variables. For this study the combined sewer system of the city of Linz in the northern part of Austria located on the Danube has been selected. The city itself represents a total area of 96 km2 with 39 municipalities connected. It was found that the available weather radar data leads to large deviations in the forecast for precipitation at forecast horizons larger than 90 minutes. The same is true for sewer variables such a CSO overflow for small sub-catchments. Although the results improve for larger spatial scales, acceptable levels at forecast horizons larger than 90 minutes are not reached.

Field Observations of Hydrodynamics, Sediment Transport, and Water and Sediment Quality in the Hudson-Raritan Estuary

NASA Astrophysics Data System (ADS)

Bruno, M. S.; Glenn, S.; Chant, R.; Rankin, K.; Korfiatis, G.; Dimou, N.; Creed, E.; Fullerton, B.; Pence, A.; Burke, P.; Haldeman, C.; Hires, R.; Hunter, E.

2002-12-01

The New York-New Jersey Harbor estuary system is of enormous ecological and economic importance to the region. The presence of toxic chemicals in the water and sediments results in reduced water quality, fisheries restrictions/advisories, and general adverse impacts to the estuarine ecosystem. The Port of New York and New Jersey is central to the economy of the region. However, in recent years, problems associated with the management of contaminated dredged material, including high costs and the lack of suitable disposal/use alternatives, have threatened to impact the volume of shipping in the Harbor. Sources of contaminants include atmospheric deposition, municipal and industrial wastewater treatment facilities, combined sewer and stormwater outfalls, and rainfall-induced runoff (non-point sources). In addition, Harbor sediments can act as a continuing source as they are re-suspended and moved throughout the system by both natural and man-made means. As part of the New Jersey Toxics Reduction Workplan, Stevens Institute of Technology and Rutgers University are conducting hydrodynamic, sediment transport, and water and suspended sediment quality measurements in Newark Bay, the Arthur Kill and the Kill van Kull. The goals of the project include: (1) collection of high resolution (event-driven and long-term) hydrodynamic, sediment transport and water and suspended sediment quality measurements for use in the assessment of the dominant physics of the system and in the development of a combined hydrodynamic-sediment transport-water/sediment quality model for the region. (2) identification of those tributaries to NY-NJ Harbor that are significant sources of the chemicals of concern, and evaluation of the importance of non-point sources and existing contaminated bottom sediments as sources of the chemicals of concern. (3) identification of point discharges that represent significant sources of the chemicals of concern. Observations were obtained over a two-year period, during 21 tributary flow "events", each having an approximate duration of 1 week. The measurement program included 3 fixed mooring stations and 5 shipboard locations. Each mooring consisted of an acoustic Doppler current profiler; a high-resolution pressure sensor; an OBS; a CTD; and a laser-based scatterometer. The ship-board measurements included vertical current profiles using a towed acoustic Doppler current profiler; CTD measurements; OBS measurements; suspended sediment concentration and particle size spectrum using a laser-based scatterometer; and chemical characterization of water and suspended sediment samples. The water and sediment quality measurements were obtained using a specially designed Trace Organics Platform Sampler. This sampler allowed for the measurement of low-level concentrations of PCBs (108 congeners), dioxins/furans, Pesticides, PAHs and metals (Hg, Cd, Pb). Preliminary analysis of the data has improved our understanding of the circulation and sediment transport patterns in this region of the estuary, including the influence of extreme tributary flow events, local winds, and anthropogenic effects such as port structures, vessels, and the navigation channels, and has identified the most highly contaminated reaches of the tributaries.

On the occurrence of rainstorm damage based on home insurance and weather data

NASA Astrophysics Data System (ADS)

Spekkers, M. H.; Clemens, F. H. L. R.; ten Veldhuis, J. A. E.

2014-08-01

Rainstorm damage caused by malfunctioning of urban drainage systems and water intrusion due to defects in the building envelope can be considerable. Little research on this topic focused on the collection of damage data, the understanding of damage mechanisms and the deepening of data analysis methods. In this paper, the relative contribution of different failure mechanisms to the occurrence of rainstorm damage are investigated, as well as the extent to which these mechanisms relate to weather variables. For a case study in Rotterdam, the Netherlands, a property level home insurance database of around 3100 water-related damage claims was analysed. Records include comprehensive transcripts of communication between insurer, insured and damage assessment experts, which allowed claims to be classified according to their actual damage cause. Results show that roof and wall leakage is the most frequent failure mechanism causing precipitation-related claims, followed by blocked roof gutters, melting snow and sewer flooding. Claims related to sewer flooding were less present in the data, but are associated with significantly larger claim sizes than claims in the majority class, i.e. roof and wall leakages. Rare events logistic regression analysis revealed that maximum rainfall intensity and rainfall volume are significant predictors for the occurrence probability of precipitation-related claims. Moreover, it was found that claims associated with rainfall intensities smaller than 7-8 mm in a 60 min window are mainly related to failures processes in the private domain, such as roof and wall leakages. For rainfall events that exceed the 7-8 mm h-1 threshold, failure of systems in the public domain, such as sewer systems, start to contribute considerably to the overall occurrence probability of claims. The communication transcripts, however, lacked information to be conclusive about to extent to which sewer-related claims were caused by overloading of sewer systems or failure of system components.

On the occurrence of rainstorm damage based on home insurance and weather data

NASA Astrophysics Data System (ADS)

Spekkers, M. H.; Clemens, F. H. L. R.; ten Veldhuis, J. A. E.

2015-02-01

Rainstorm damage caused by the malfunction of urban drainage systems and water intrusion due to defects in the building envelope can be considerable. Little research on this topic focused on the collection of damage data, the understanding of damage mechanisms and the deepening of data analysis methods. In this paper, the relative contribution of different failure mechanisms to the occurrence of rainstorm damage is investigated, as well as the extent to which these mechanisms relate to weather variables. For a case study in Rotterdam, the Netherlands, a property level home insurance database of around 3100 water-related damage claims was analysed. The records include comprehensive transcripts of communication between insurer, insured and damage assessment experts, which allowed claims to be classified according to their actual damage cause. The results show that roof and wall leakage is the most frequent failure mechanism causing precipitation-related claims, followed by blocked roof gutters, melting snow and sewer flooding. Claims related to sewer flooding were less present in the data, but are associated with significantly larger claim sizes than claims in the majority class, i.e. roof and wall leakages. Rare events logistic regression analysis revealed that maximum rainfall intensity and rainfall volume are significant predictors for the occurrence probability of precipitation-related claims. Moreover, it was found that claims associated with rainfall intensities smaller than 7-8 mm in a 60-min window are mainly related to failure processes in the private domain, such as roof and wall leakages. For rainfall events that exceed the 7-8 mm h-1 threshold, the failure of systems in the public domain, such as sewer systems, start to contribute considerably to the overall occurrence probability of claims. The communication transcripts, however, lacked information to be conclusive about to which extent sewer-related claims were caused by overloading of sewer systems or failure of system components.

Research of trace metals as markers of entry pathways in combined sewers.

PubMed

Gounou, C; Varrault, G; Amedzro, K; Gasperi, J; Moilleron, R; Garnaud, S; Chebbo, G

2011-01-01

Combined sewers receive high toxic trace metal loads emitted by various sources, such as traffic, industry, urban heating and building materials. During heavy rain events, Combined Sewer Overflows (CSO) can occur and, if so, are discharged directly into the aquatic system and therefore could have an acute impact on receiving waters. In this study, the concentrations of 18 metals have been measured in 89 samples drawn from the three pollutant Entry Pathways in Combined Sewers (EPCS): i) roof runoff, ii) street runoff, and iii) industrial and domestic effluents and also drawn from sewer deposits (SD). The aim of this research is to identify metallic markers for each EPCS; the data matrix was submitted to principal component analysis in order to determine metallic markers for the three EPCS and SD. This study highlights the fact that metallic content variability across samples from different EPCS and SD exceeds the spatio-temporal variability of samples from the same EPCS. In the catchment studied here, the most valuable EPCS and SD markers are lead, sodium, boron, antimony and zinc; these markers could be used in future studies to identify the contributions of each EPCS to CSO metallic loads.

Tertiary Treatment and Recycling of Wastewater

DTIC Science & Technology

2015-05-18

of the Worrell design (Figure 2.1) illustrates the modular treatment cells filled with vitrified expanded clay (or similar media) and planted with...General Construction Storm Water permit Sanitary / Storm Drainage Restriction: Absolutely no materials are to be disposed of via the sanitary ...sewer or storm water systems without consulting the Environmental Office. Exception: Water may be discharged down the sanitary sewer when:  The

High-Throughput Amplicon Sequencing Reveals Distinct Communities within a Corroding Concrete Sewer System

PubMed Central

Dennis, Paul G.; Keller, Jurg; Tyson, Gene W.

2012-01-01

Microbially induced concrete corrosion (MICC) is an important problem in sewers. Here, small-subunit (SSU) rRNA gene amplicon pyrosequencing was used to characterize MICC communities. Microbial community composition differed between wall- and ceiling-associated MICC layers. Acidithiobacillus spp. were present at low abundances, and the communities were dominated by other sulfur-oxidizing-associated lineages. PMID:22843532

QUANTIFICATION OF METHANE EMISSIONS AND DISCUSSON OF NITROUS OXIDE, AND AMMONIA EMISSIONS FROM SEPTIC TANKS, LATRINES, AND STAGNANT OPEN SEWERS OF THE WORLD

EPA Science Inventory

The report gives results of a first attempt to estimate global and country-specific methane (CH4) emissons from sewers and on-site wastewater treatment systems, including latrines and septic sewage tanks. It follows a report that includes CH4 and nitrous oxide (N2O) estimates fro...

Forensic applications of nitrogen and oxygen isotopes in tracing nitrate sources in urban environments

USGS Publications Warehouse

Silva, S.R.; Ging, P.B.; Lee, R.W.; Ebbert, J.C.; Tesoriero, A.J.; Inkpen, E.L.

2002-01-01

Ground and surface waters in urban areas are susceptible to nitrate contamination from septic systems, leaking sewer lines, and fertilizer applications. Source identification is a primary step toward a successful remediation plan in affected areas. In this respect, nitrogen and oxygen isotope ratios of nitrate, in conjunction with hydrologic data and water chemistry, have proven valuable in urban studies from Austin, Texas, and Tacoma, Washington. In Austin, stream water was sampled during stremflow and baseflow conditions to assess surface and subsurface sources of nitrate, respectively. In Tacoma, well waters were sampled in adjacent sewered and un-sewered areas to determine if locally high nitrate concentrations were caused by septic systems in the un-sewered areas. In both studies, sewage was identified as a nitrate source and mixing between sewage and other sources of nitrate was apparent. In addition to source identification, combined nitrogen and oxygen isotopes were important in determining the significance of denitrification, which can complicate source assessment by reducing nitrate concentrations and increasing ??15N values. The two studies illustrate the value of nitrogen and oxygen isotopes of nitrate for forensic applications in urban areas. ?? Published by Elsevier Science Ltd. on behalf of AEHS.

Environmental Impact Statement For the Disposal and Reuse of Hunters Point Shipyard Volume 2: Response to Comments

DTIC Science & Technology

2000-03-01

discussed. There are two requirements of the permit designed to meet the goals of the program: 1) design and implementation of BMPs to control runoff...affect these species. NMFS is aware that specific upgrades to the sanitary sewer and storm drainage systems have yet to be designed and the proposed...Specific 8 upgrades to the sanitary sewer and storm drainage systems, though not yet designed , 9 will meet both City and County of San Francisco and

Evidence of a sewer vapor transport pathway at the USEPA ...

EPA Pesticide Factsheets

The role of sewer lines as preferential pathways for vapor intrusion is poorly understood. Although the importance of sewer lines for volatile organic compound (VOC) transport has been documented at a small number of sites with vapor intrusion, sewer lines are not routinely sampled during most vapor intrusion investigations. We have used a tracer study and VOC concentration measurements to evaluate the role of the combined sanitary/storm sewer line in VOC transport at the USEPA vapor intrusion research duplex in Indianapolis, Indiana. The results from the tracer study demonstrated gas migration from the sewer main line into the duplex. The migration pathway appears to be complex and may include leakage from the sewer lateral at a location below the building foundation. Vapor samples collected from the sewer line demonstrated the presence of tetrachloroethene (PCE) and chloroform in the sewer main in front of the duplex and at multiple sample locations within the sewer line upstream of the duplex. These test results combined with results from the prior multi-year study of the duplex indicate that the sewer line plays an important role in transport of VOCs from the subsurface source to the immediate vicinity of the duplex building envelope. Highlights • The sewer line is an important pathway for VOC transport at the USEPA duplex. • The importance of this pathway was not identified during prior study of the duplex. • Sewer lines should be routinely evaluated

Development and evaluation of a decision-supporting model for identifying the source location of microbial intrusions in real gravity sewer systems.

PubMed

Kim, Minyoung; Choi, Christopher Y; Gerba, Charles P

2013-09-01

Assuming a scenario of a hypothetical pathogenic outbreak, we aimed this study at developing a decision-support model for identifying the location of the pathogenic intrusion as a means of facilitating rapid detection and efficient containment. The developed model was applied to a real sewer system (the Campbell wash basin in Tucson, AZ) in order to validate its feasibility. The basin under investigation was divided into 14 sub-basins. The geometric information associated with the sewer network was digitized using GIS (Geological Information System) and imported into an urban sewer network simulation model to generate microbial breakthrough curves at the outlet. A pre-defined amount of Escherichia coli (E. coli), which is an indicator of fecal coliform bacteria, was hypothetically introduced into 56 manholes (four in each sub-basin, chosen at random), and a total of 56 breakthrough curves of E. coli were generated using the simulation model at the outlet. Transport patterns were classified depending upon the location of the injection site (manhole), various known characteristics (peak concentration and time, pipe length, travel time, etc.) extracted from each E. coli breakthrough curve and the layout of sewer network. Using this information, we back-predicted the injection location once an E. coli intrusion was detected at a monitoring site using Artificial Neural Networks (ANNs). The results showed that ANNs identified the location of the injection sites with 57% accuracy; ANNs correctly recognized eight out of fourteen expressions with relying on data from a single detection sensor. Increasing the available sensors within the basin significantly improved the accuracy of the simulation results (from 57% to 100%). Copyright © 2013 Elsevier Ltd. All rights reserved.

Coupled 1-D sewer and street networks and 2-D flooding model to rapidly evaluate surface inundation

NASA Astrophysics Data System (ADS)

Kao, Hong-Ming; Hsu, Hao-Ming

2017-04-01

Flash floods have occurred frequently in the urban areas around the world and cause the infrastructure and people living to expose continuously in the high risk level of pluvial flooding. According to historical surveys, the major reasons of severe surface inundations in the urban areas can be attributed to heavy rainfall in the short time and/or drainage system failure. In order to obtain real-time flood forecasting with high accuracy and less uncertainty, an appropriate system for predicting floods is necessary. For the reason, this study coupled 1-D sewer and street networks and 2-D flooding model as an operational modelling system for rapidly evaluating surface inundation. The proposed system is constructed by three significant components: (1) all the rainfall-runoff of a sub-catchment collected via gullies is simulated by the RUNOFF module of the Storm Water Management Model (SWMM); (2) and directly drained to the 1-D sewer and street networks via manholes as inflow discharges to conduct flow routing by using the EXTRAN module of SWMM; (3) after the 1-D simulations, the surcharges from manholes are considered as point sources in 2-D overland flow simulations that are executed by the WASH123D model. It can thus be used for urban flood modelling that reflects the rainfall-runoff processes, and the dynamic flow interactions between the storm sewer system and the ground surface in urban areas. In the present study, we adopted the Huwei Science and Technology Park, located in the south-western part of Taiwan, as the demonstration area because of its high industrial values. The region has an area about 1 km2 with approximately 1 km in both length and width. It is as isolated urban drainage area in which there is a complete sewer system that collects the runoff and drains to the detention pond. Based on the simulated results, the proposed modelling system was found that the simulated floods fit to the survey records because the physical rainfall-runoff phenomena in urban environment were better reflected. Keywords: SWMM, WASH123D, surface inundation, real-time.

From mess to mass: a methodology for calculating storm event pollutant loads with their uncertainties, from continuous raw data time series.

PubMed

Métadier, M; Bertrand-Krajewski, J-L

2011-01-01

With the increasing implementation of continuous monitoring of both discharge and water quality in sewer systems, large data bases are now available. In order to manage large amounts of data and calculate various variables and indicators of interest it is necessary to apply automated methods for data processing. This paper deals with the processing of short time step turbidity time series to estimate TSS (Total Suspended Solids) and COD (Chemical Oxygen Demand) event loads in sewer systems during storm events and their associated uncertainties. The following steps are described: (i) sensor calibration, (ii) estimation of data uncertainties, (iii) correction of raw data, (iv) data pre-validation tests, (v) final validation, and (vi) calculation of TSS and COD event loads and estimation of their uncertainties. These steps have been implemented in an integrated software tool. Examples of results are given for a set of 33 storm events monitored in a stormwater separate sewer system.

Rainwater drainage management for urban development based on public-private partnership.

PubMed

Matsushita, J; Ozaki, M; Nishimura, S; Ohgaki, S

2001-01-01

The Urban Development Corporation (UDC) is one of the biggest implementation bodies for urban development in Japan. UDC has developed rainwater infiltration technology since 1975. This technology has effectively reduced runoff to a river and sewer system in the new town project areas. Recently, UDC has developed a new system which is defined as a "Rainwater Recycle Sewer System", which is supported by "Rainwater Storage and Infiltration Technology (RSIT)" applicable to new town creation and urban renewal. The new system consists of two elements: RSIT components based on Public-Private Partnership (PPP) and a stormwater drainage system. Herein, the private sector is responsible for the main part of RSIT, and the public sector is responsible for the stormwater drainage from the development area. As a result, the capacity of public facilities, such as rainwater sewers and stormwater reservoirs, can be reduced effectively. In parallel, the initial/running cost of public facilities is expected to be reduced. In conclusion, the authors would stress the importance of a co-maintenance system also based on PPP, which will be required especially in order to properly operate the whole system for the long term.

CHARACTERIZING THE ORGANIC MATTER IN SURFACE ...

EPA Pesticide Factsheets

The San Juan Bay Estuary (SJBE) is located on the north coast of Puerto Rico and includes the San Juan Bay, San José Lagoon, La Torrecilla Lagoon and Piñones Lagoon, as well as the Martín Peña and the Suárez Canals. The SJBE watershed has the highest density of inhabitants and major industrial activities in Puerto Rico. As a result, the SJBE is impacted by wastewater from combined-sewer overflows, faulty sewer lines, and storm water runoff; these factors combined with trash accumulation and infilling of the Martín Peña canal, contribute to decreased tidal exchange and reduced flushing in the estuary. To quantify the impact of the obstruction of the Martín Peña canal on anthropogenic nutrient distribution in the SJBE, over 200 sediment grab samples were collected throughout the estuary in 2015. The samples were analyzed for carbonate content, organic matter, grain size, bulk density, percent phosphorus, percent nitrogen (%N), and stable isotopes (δ15N and δ13C). The %N values were highest in the surface sediments from the western portion of the Martín Peña canal, where %N was >0.86%. In contrast, %N from the adjacent San José lagoon averaged <0.2%. Grain size distributions across the SJBE were consistent with low flushing in the inner portions of the SJBE. While the Martín Peña canal remains phosphorus limited, N:P ratios suggest the San Juna Bay and San José Lagoon have undergone major ecological shifts in the past two decades. Our

The Geochemical Record of Cultural Eutrophication and Remediation Efforts in Three Connecticut Lakes

NASA Astrophysics Data System (ADS)

Ku, T.; Bourne, H. L.; Tirtajana, S.; Nahar, M.; Kading, T.

2009-12-01

Cultural eutrophication is the process whereby human activity increases the amount of nutrients, primarily nitrogen and phosphorous, entering an aquatic ecosystem causing excessive biological growth. To reverse or decelerate cultural eutrophication, many regulatory agencies have implemented stringent laws intended to lower the flux of nutrients into impacted water bodies or have emplaced internal remediation systems designed to decrease primary productivity. To quantify the effects of cultural eutrophication and remediation efforts, we examined sedimentary histories of three eutrophic Connecticut lakes that record the transition from pre-anthropogenic conditions into eutrophication and through recent remediation. The three Connecticut lakes (Lake Waramaug, Beseck Lake, and Amos Lake) represent a range of remediation activities. Since 1983, Lake Waramaug has been the focus of significant remediation efforts including the installation of three hypolimnetic withdrawal / layer aeration systems, zoning regulations to limit runoff, and the stocking and seeding of fish and zooplankton. Beseck Lake has experienced episodic eutrophic conditions, in part due to failing septic systems, and in 2001, 433 residences were converted from septic systems to a city sewer system. Amos Lake serves as a cultural eutrophication end member as it has not has received any major remediation. Multiple freeze and gravity cores were collected from 2005-2008. Radiocarbon, Pb-210, Cs-137, Hg, and Pb measurements determined sediment ages. Organic C accumulation rates, C/N ratios, organic matter delta-15N, bulk sediment Fe and Al concentrations, and P speciation (labile, iron-bound, aluminum-bound, organic, and total) determined sediment and nutrient sources and accumulations. Dithionite-extractable iron, pyrite S, and pyrite delta-34S provided insight into changes in P-Fe-S cycling. The sediment cores represent the last few hundreds of years of lake history and, importantly, some Lake Waramaug freeze cores preserved the sediments deposited after remediation efforts began. European settlement beginning in the 1700s caused an increase in total P and organic C sedimentation rates, a decrease in C/N, an increase in delta-15N, and an increase in allochthonous aluminosilicate sedimentation. The increase in delta-15N since the 1700s was caused the influx of high delta-15N sources such as agricultural fertilizers. In some Lake Waramaug cores, delta-15N has decreased in the last few decades, likely in response to new zoning laws, and demonstrates that remediation efforts have successfully altered nutrient inputs into the lake. Increased nutrient and aluminosilicate inputs during the 1800 and 1900s caused the dominant sediment P reservoir to shift from organic-P to Fe- or Al- bound P. In some cases, Fe-bound P decreased when pyrite S concentrations increased and d34S values decreased, suggesting that increased atmospheric sulfur inputs and subsequent pyritization has decreased the iron available to bind phosphorus. This work expands our knowledge of recovering aquatic systems and shows that recent sediment records may be used to measure the success of remediation strategies.

Evidence of a sewer vapor transport pathway at the USEPA vapor intrusion research duplex.

PubMed

McHugh, Thomas; Beckley, Lila; Sullivan, Terry; Lutes, Chris; Truesdale, Robert; Uppencamp, Rob; Cosky, Brian; Zimmerman, John; Schumacher, Brian

2017-11-15

The role of sewer lines as preferential pathways for vapor intrusion is poorly understood. Although the importance of sewer lines for volatile organic compound (VOC) transport has been documented at a small number of sites with vapor intrusion, sewer lines are not routinely sampled during most vapor intrusion investigations. We have used a tracer study and VOC concentration measurements to evaluate the role of the combined sanitary/storm sewer line in VOC transport at the USEPA vapor intrusion research duplex in Indianapolis, Indiana. The results from the tracer study demonstrated gas migration from the sewer main line into the duplex. The migration pathway appears to be complex and may include leakage from the sewer lateral at a location below the building foundation. Vapor samples collected from the sewer line demonstrated the presence of tetrachloroethene (PCE) and chloroform in the sewer main in front of the duplex and at multiple sample locations within the sewer line upstream of the duplex. These test results combined with results from the prior multi-year study of the duplex indicate that the sewer line plays an important role in transport of VOCs from the subsurface source to the immediate vicinity of the duplex building envelope. Copyright © 2017 Elsevier B.V. All rights reserved.

Evidence of a sewer vapor transport pathway at the USEPA vapor intrusion research duplex

DOE PAGES

McHugh, Thomas; Beckley, Lila; Sullivan, Terry; ...

2017-04-26

We report the role of sewer lines as preferential pathways for vapor intrusion is poorly understood. Although the importance of sewer lines for volatile organic compound (VOC) transport has been documented at a small number of sites with vapor intrusion, sewer lines are not routinely sampled during most vapor intrusion investigations. We have used a tracer study and VOC concentration measurements to evaluate the role of the combined sanitary/storm sewer line in VOC transport at the USEPA vapor intrusion research duplex in Indianapolis, Indiana. The results from the tracer study demonstrated gas migration from the sewer main line into themore » duplex. The migration pathway appears to be complex and may include leakage from the sewer lateral at a location below the building foundation. Vapor samples collected from the sewer line demonstrated the presence of tetrachloroethene (PCE) and chloroform in the sewer main in front of the duplex and at multiple sample locations within the sewer line upstream of the duplex. Finally, these test results combined with results from the prior multi-year study of the duplex indicate that the sewer line plays an important role in transport of VOCs from the subsurface source to the immediate vicinity of the duplex building envelope.« less

Evidence of a sewer vapor transport pathway at the USEPA vapor intrusion research duplex

DOE Office of Scientific and Technical Information (OSTI.GOV)

McHugh, Thomas; Beckley, Lila; Sullivan, Terry

We report the role of sewer lines as preferential pathways for vapor intrusion is poorly understood. Although the importance of sewer lines for volatile organic compound (VOC) transport has been documented at a small number of sites with vapor intrusion, sewer lines are not routinely sampled during most vapor intrusion investigations. We have used a tracer study and VOC concentration measurements to evaluate the role of the combined sanitary/storm sewer line in VOC transport at the USEPA vapor intrusion research duplex in Indianapolis, Indiana. The results from the tracer study demonstrated gas migration from the sewer main line into themore » duplex. The migration pathway appears to be complex and may include leakage from the sewer lateral at a location below the building foundation. Vapor samples collected from the sewer line demonstrated the presence of tetrachloroethene (PCE) and chloroform in the sewer main in front of the duplex and at multiple sample locations within the sewer line upstream of the duplex. Finally, these test results combined with results from the prior multi-year study of the duplex indicate that the sewer line plays an important role in transport of VOCs from the subsurface source to the immediate vicinity of the duplex building envelope.« less

Evaluation of effectiveness of combined sewer overflow control measures by operational data.

PubMed

Schroeder, K; Riechel, M; Matzinger, A; Rouault, P; Sonnenberg, H; Pawlowsky-Reusing, E; Gnirss, R

2011-01-01

The effect of combined sewer overflow (CSO) control measures should be validated during operation based on monitoring of CSO activity and subsequent comparison with (legal) requirements. However, most CSO monitoring programs have been started only recently and therefore no long-term data is available for reliable efficiency control. A method is proposed that focuses on rainfall data for evaluating the effectiveness of CSO control measures. It is applicable if a sufficient time-series of rainfall data and a limited set of data on CSO discharges are available. The method is demonstrated for four catchments of the Berlin combined sewer system. The analysis of the 2000-2007 data shows the effect of CSO control measures, such as activation of in-pipe storage capacities within the Berlin system. The catchment, where measures are fully implemented shows less than 40% of the CSO activity of those catchments, where measures have not yet or not yet completely been realised.

Programmatic Environmental Assessment, Francis E. Warren Air Force Base, Wyoming

DTIC Science & Technology

2005-12-17

disturbance negatively affected wetlands along these drainages: old refuse dumps were established and remain along portions of Crow Creek, and growth of...avense), common hound’s tongue (Cynoglossum officinale ), field Programmatic Environmental Assessment F. E. Warren AFB 68 bindweed (Convolvulus...finding its way into the sewer through inflow and infiltration. In terms of total flow capacity, the sanitary sewer system can support moderate growth

Application of Morphological Segmentation to Leaking Defect Detection in Sewer Pipelines

PubMed Central

Su, Tung-Ching; Yang, Ming-Der

2014-01-01

As one of major underground pipelines, sewerage is an important infrastructure in any modern city. The most common problem occurring in sewerage is leaking, whose position and failure level is typically idengified through closed circuit television (CCTV) inspection in order to facilitate rehabilitation process. This paper proposes a novel method of computer vision, morphological segmentation based on edge detection (MSED), to assist inspectors in detecting pipeline defects in CCTV inspection images. In addition to MSED, other mathematical morphology-based image segmentation methods, including opening top-hat operation (OTHO) and closing bottom-hat operation (CBHO), were also applied to the defect detection in vitrified clay sewer pipelines. The CCTV inspection images of the sewer system in the 9th district, Taichung City, Taiwan were selected as the experimental materials. The segmentation results demonstrate that MSED and OTHO are useful for the detection of cracks and open joints, respectively, which are the typical leakage defects found in sewer pipelines. PMID:24841247

Bayesian decision analysis as a tool for defining monitoring needs in the field of effects of CSOs on receiving waters.

PubMed

Korving, H; Clemens, F

2002-01-01

In recent years, decision analysis has become an important technique in many disciplines. It provides a methodology for rational decision-making allowing for uncertainties in the outcome of several possible actions to be undertaken. An example in urban drainage is the situation in which an engineer has to decide upon a major reconstruction of a system in order to prevent pollution of receiving waters due to CSOs. This paper describes the possibilities of Bayesian decision-making in urban drainage. In particular, the utility of monitoring prior to deciding on the reconstruction of a sewer system to reduce CSO emissions is studied. Our concern is with deciding whether a price should be paid for new information and which source of information is the best choice given the expected uncertainties in the outcome. The influence of specific uncertainties (sewer system data and model parameters) on the probability of CSO volumes is shown to be significant. Using Bayes' rule, to combine prior impressions with new observations, reduces the risks linked with the planning of sewer system reconstructions.

Stable isotopes of water as a natural tracer for infiltration into urban sewer systems

NASA Astrophysics Data System (ADS)

Kracht, O.; Gresch, M.; de Bénédittis, J.; Prigiobbe, V.; Gujer, W.

2003-04-01

An adequate understanding of the hydraulic interaction between leaky sewers and groundwater is essential for the sustainable management of both sewer systems and aquifers in urbanized areas. Undesirable infiltration of groundwater into sewers can contribute over 50% of the total discharge and is detrimental to treatment plant efficiency. On the other hand, in many European cities groundwater surface levels seem to be particularly controlled by the drainage effect of permeable sewer systems. However, nowadays methods for the quantification of these exchange processes are still subject to considerable uncertainties due to their underlying assumptions. The frequently used assumption that the night time minimum in the diurnal wastewater hydrograph is equal to the "parasitic discharge" has to be reconsidered to today's patterns of human life as well as to the long residence time of wastewater in the sewer networks of modern cities. The suitability of stable water isotopes as a natural tracer to differentiate the origin of water in the sewer ("real" wastewater or infiltrating groundwater) is currently investigated in three different catchment areas. The studies are carried out within the framework of the European research project APUSS (Assessing Infiltration and Exfiltration on the Performance of Urban Sewer Systems): 1) The village of Rümlang (Zürich, Switzerland) is predominantly served with drinking water from the Lake Zürich. A large fraction of the lakes water is derived from precipitation in the Alps. This drinking water represents the intrinsic provenience of the wastewater with an δ18O value around -11,5 per mill and δ^2H value around -82 per mill vs. SMOW. In contrast, the local groundwater is originating from precipitation in a moderate altitude of about 450 m above sea level and shows comparatively enriched mean δ18O values of -9,7 per mill and δ^2H values of -70 per mill with only small natural variations. The isotopic separation between these endmembers is basically sufficient to estimate the ratio of infiltrating water in the sewer. Uncertainties yet derive from varying amounts of local groundwater in the water supply mains. These will be substituted by additionally purchased lake water in the next experimental stage. 2) The experimental site Toraccia (suburb of Rome, Italy) obtains drinking water from the Peschiera springs group that is situated in the central Apennines chain about 90 km north east of Rome. This spring water is transported to Rome by an aqueduct. A first campaign revealed an average mains water δ18O value of -8,4 per mill and δ^2H value of -53 per mill. Potential sources of infiltration are occurrences of perched groundwater. These appear to be enriched compared to the drinking water about 2 to 3 per mill in the δ18O and 10 to 20 per mill in the δ^2H value, but show disadvantageous strong variations. 3) Investigations in the urban area of Lyon (France) benefit from the isotopic differences between underground waters originating from the two rivers Rhone and Saone and their associated alluvial aquifers. The oxygen isotope composition of the Rhone water is roughly 3 per mill lighter than that of the river Saone, due to the large differences in the mean altitude and topographic situation of their catchment basins. Considerable amounts of mains water are extracted by production wells in the Rhone aquifer. In consequence a usable difference in the oxygen isotope composition between wastewater and local groundwater of about 1.5 per mill is available for application studies in certain parts of the city.

Sedimentation survey of Lago Caonillas, Utuado, Puerto Rico, September–November 2012

USGS Publications Warehouse

Soler-Lopez, Luis R.

2016-11-09

During September–November 2012, the U.S. Geological Survey, in cooperation with the Puerto Rico Aqueduct and Sewer Authority, conducted a sedimentation survey of Lago Caonillas to estimate current (2012) reservoir storage capacity and the recent (2000–2012) reservoir sedimentation rate by comparing the 2012 bathymetric survey data with the February 2000 data. The Lago Caonillas storage capacity, which was 42.27 million cubic meters in February 2000, decreased to 39.55 million cubic meters by September–November 2012. The intersurvey (2000–2012) storage capacity loss was about 6 percent, corresponding to a decrease of about 0.5 percent per year; this loss represents a reservoir sedimentation rate of about 226,670 cubic meters per year between 2000 and 2012. On a long-term basis, however, the sedimentation rate has remained nearly constant, decreasing from about 257,500 to 251,720 cubic meters per year during 1948–2000 and 1948–2012, respectively. Most of the sediment accumulation and associated storage capacity loss of Lago Caonillas has occurred within the eastern and Río Caonillas branches of the reservoir. In the vicinity of the Caonillas Dam, minor sediment deposition and scour have occurred. The Lago Caonillas drainage area sediment yield has decreased by about 2 percent since the previous survey, from 1,266 cubic meters per square kilometer per year in 2000 to 1,237 cubic meters per square kilometer per year in 2012. If the long-term sedimentation rate of 251,720 cubic meters per year remains constant, the useful life of Lago Caonillas may end in about 2169.

STORM-SEWER FLOW MEASUREMENT AND RECORDING SYSTEM.

USGS Publications Warehouse

Kilpatrick, Frederick A.; Kaehrle, William R.

1986-01-01

A comprehensive study and development of instruments and techniques for measuring all components of flow in a storm-sewer drainage system were undertaken by the U. S. Geological Survey under the sponsorship of FHWA. The study involved laboratory and field calibration and testing of measuring flumes, pipe insert meters, weirs, and electromagnetic velocity meters as well as the development and calibration of pneumatic bubbler and pressure transducer head-measuring systems. Tracer dilution and acoustic-flowmeter measurements were used in field verification tests. A single micrologger was used to record data from all the instruments and also to activate on command the electromagnetic velocity meter and tracer dilution systems.

Investigating the interactions of decentralized and centralized wastewater heat recovery systems.

PubMed

Sitzenfrei, Robert; Hillebrand, Sebastian; Rauch, Wolfgang

2017-03-01

In the urban water cycle there are different sources for extracting energy. In addition to potential and chemical energy in the wastewater, thermal energy can also be recovered. Heat can be recovered from the wastewater with heat exchangers that are located decentralized and/or centralized at several locations throughout the system. It can be recovered directly at the source (e.g. in the showers and bathrooms), at building block level (e.g. warm water tanks collecting all grey water), in sewers or at the wastewater treatment plant. However, an uncoordinated installation of systems on such different levels can lead to competing technologies. To investigate these interactions, a modelling environment is set up, tested and calibrated based on continuous sewer temperature and flow measurements. With that approach different heat recovery scenarios on a household level (decentralized) and of in-sewer heat recovery (centralized) are investigated. A maximum performance drop of 40% for a centralized energy recovery system was estimated when all bathrooms are equipped with decentralized recovery systems. Therefore, the proposed modelling approach is suitable for testing different future conditions and to identify robust strategies for heat recovery systems from wastewater.

Simulation of the wastewater temperature in sewers with TEMPEST.

PubMed

Dürrenmatt, David J; Wanner, Oskar

2008-01-01

TEMPEST is a new interactive simulation program for the estimation of the wastewater temperature in sewers. Intuitive graphical user interfaces assist the user in managing data, performing calculations and plotting results. The program calculates the dynamics and longitudinal spatial profiles of the wastewater temperature in sewer lines. Interactions between wastewater, sewer air and surrounding soil are modeled in TEMPEST by mass balance equations, rate expressions found in the literature and a new empirical model of the airflow in the sewer. TEMPEST was developed as a tool which can be applied in practice, i.e., it requires as few input data as possible. These data include the upstream wastewater discharge and temperature, geometric and hydraulic parameters of the sewer, material properties of the sewer pipe and surrounding soil, ambient conditions, and estimates of the capacity of openings for air exchange between sewer and environment. Based on a case study it is shown how TEMPEST can be applied to estimate the decrease of the downstream wastewater temperature caused by heat recovery from the sewer. Because the efficiency of nitrification strongly depends on the wastewater temperature, this application is of practical relevance for situations in which the sewer ends at a nitrifying wastewater treatment plant.

PPCPs wet weather mobilization in a combined sewer in NW Spain.

PubMed

Del Río, Héctor; Suárez, Joaquín; Puertas, Jerónimo; Ures, Pablo

2013-04-01

An intense campaign was carried out over a 14 month period to characterize concentrations and loads of 7 well-known Pharmaceuticals and Personal Care Products (PPCPs), during dry and wet weather conditions, in an urban combined catchment in the northwest of Spain, a geographical zone with an average annual rainfall over 1500 mm. The main objective was to gather more in-depth knowledge of the mobilization of these "micropollutants" in an urban combined sewer and the possible pressures on water receiving bodies due to combined sewer overflows (CSOs). Hydrographs and pollutographs of these substances in dry weather flows (DWF), on weekdays and weekends, and wet weather flows (WWF) during 10 rain events have been characterized to obtain data that are sufficiently representative for statistical analysis. The research findings show that there is a considerable mobilization of these substances during rain events, mainly in the first part of the hydrographs, especially HHCB galaxolide, ibuprofen and paracetamol with maximum concentrations of 9.76, 8.51 and 5.71 μg/L respectively, whereas these concentrations in dry weather only reached 2.57, 2.11 and 0.72 μg/L respectively. There is a good correlation between the degree of mobilization in wet weather flows and the percentage of dry weather particulate phase of each studied substance, indicating that such mobilization may be associated with adsorption on the sediments deposited on the collectors during the antecedent dry period. These results are in good agreement with removal in conventional WWTP, especially for compounds that tend to adsorb onto sewage sludge. Copyright © 2013 Elsevier B.V. All rights reserved.

Damage estimation of sewer pipe using subtitles of CCTV inspection video

NASA Astrophysics Data System (ADS)

Park, Kitae; Kim, Byeongcheol; Kim, Taeheon; Seo, Dongwoo

2017-04-01

Recent frequent occurrence of urban sinkhole serves as a momentum of the periodic inspection of sewer pipelines. Sewer inspection using a CCTV device needs a lot of time and efforts. Many of previous studies which reduce the laborious tasks are mainly interested in the developments of image processing S/W and exploring H/W. And there has been no attempt to find meaningful information from the existing CCTV images stored by the sewer maintenance manager. This study adopts a cross-correlation based image processing method and extracts sewer inspection device's location data from CCTV images. As a result of the analysis of location-time relation, it show strong correlation between device stand time and the sewer damages. In case of using this method to investigate sewer inspection CCTV images, it will save the investigator's efforts and improve sewer maintenance efficiency and reliability.

Palatability and efficacy of bromadiolone rodenticide block bait previously exposed to environmental conditions.

PubMed

Nakagawa, Lia; de Masi, Eduardo; Narciso, Emerson; Neto, Hildebrando Montenegro; Papini, Solange

2015-10-01

In São Paulo city, rodent infestation is considered to be a serious public health problem and is the object of a municipal rodent control programme. One of the most important routine methods involves baiting in sewers, using bromadiolone block bait in a pulsed baiting strategy. It has been observed that, after each pulse, bait is not always consumed, and its appearance is altered, which has led to concerns about efficacy. We assessed whether exposure to sewer conditions influences the palatability and efficacy of rodenticide baits to Norway rats (Rattus norvegicus). Baits containing bromadiolone as active ingredient were placed in sewers, removed after 30 days and offered to rats in a two-choice food trial and a no-choice food trial. The appearance of the rodenticide baits changed after 30 days exposure to sewer conditions, but they continued to be palatable and effective against rats. The level of mortality was considered to be satisfactory, 75% in the two-choice food trial and 100% in the no-choice food trial. Results support the reuse of rodenticide block bait in rodent control. It seems to be justified to continue using/reuse baits even when their appearance has changed after 30 days exposure in sewer systems. © 2014 Society of Chemical Industry.

Improved sulfide mitigation in sewers through on-line control of ferrous salt dosing.

PubMed

Ganigué, Ramon; Jiang, Guangming; Liu, Yiqi; Sharma, Keshab; Wang, Yue-Cong; Gonzalez, José; Nguyen, Tung; Yuan, Zhiguo

2018-05-15

Water utilities worldwide spend annually billions of dollars to control sulfide-induced corrosion in sewers. Iron salts chemically oxidize and/or precipitate dissolved sulfide in sewage and are especially used in medium- and large-size sewers. Iron salt dosing rates are defined ad hoc, ignoring variation in sewage flows and sulfide levels. This often results in iron overdosing or poor sulfide control. Online dosing control can adjust the chemical dosing rates to current (and future) state of the sewer system, allowing high-precision, stable and cost-effective sulfide control. In this paper, we report a novel and robust online control strategy for the dosing of ferrous salt in sewers. The control considers the fluctuation of sewage flow, pH, sulfide levels and also the perturbation from rainfall. Sulfide production in the pipe is predicted using auto-regressive models (AR) based on current flow measurements, which in turn can be used to determine the dose of ferrous salt required for cost-effective sulfide control. Following comprehensive model-based assesment, the control was successfully validated and its effectiveness demonstrated in a 3-week field trial. The online control algorithm controlled sulfide below the target level (0.5 mg S/L) while reducing chemical dosing up to 30%. Copyright © 2018 Elsevier Ltd. All rights reserved.

Superfund explanation of significant difference for the record of decision (EPA region 2): Love Canal, Niagara Falls, NY, September 5, 1996

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

The United States Environmental Protection Agency (EPA) and the New York State Department of Environmental Conservation (NYSDEC) announce this Explanation of Significant Differences (ESD) to explain modifications to the selected remedy for the final destruction and disposal of Love Canal dioxin-contaminated sewer and creek sediments. These modifications are embodied in proposed changes to a partial consent decree between the United States and the State of New York and the Occidental Chemical Corporation (OCC) in the United States District Court for the Western District of New York.

Towards robust optimal design of storm water systems

NASA Astrophysics Data System (ADS)

Marquez Calvo, Oscar; Solomatine, Dimitri

2015-04-01

In this study the focus is on the design of a storm water or a combined sewer system. Such a system should be capable to handle properly most of the storm to minimize the damages caused by flooding due to the lack of capacity of the system to cope with rain water at peak times. This problem is a multi-objective optimization problem: we have to take into account the minimization of the construction costs, the minimization of damage costs due to flooding, and possibly other criteria. One of the most important factors influencing the design of storm water systems is the expected amount of water to deal with. It is common that this infrastructure is developed with the capacity to cope with events that occur once in, say 10 or 20 years - so-called design rainfall events. However, rainfall is a random variable and such uncertainty typically is not taken explicitly into account in optimization. Rainfall design data is based on historical information of rainfalls, but many times this data is based on unreliable measures; or in not enough historical information; or as we know, the patterns of rainfall are changing regardless of historical information. There are also other sources of uncertainty influencing design, for example, leakages in the pipes and accumulation of sediments in pipes. In the context of storm water or combined sewer systems design or rehabilitation, robust optimization technique should be able to find the best design (or rehabilitation plan) within the available budget but taking into account uncertainty in those variables that were used to design the system. In this work we consider various approaches to robust optimization proposed by various authors (Gabrel, Murat, Thiele 2013; Beyer, Sendhoff 2007) and test a novel method ROPAR (Solomatine 2012) to analyze robustness. References Beyer, H.G., & Sendhoff, B. (2007). Robust optimization - A comprehensive survey. Comput. Methods Appl. Mech. Engrg., 3190-3218. Gabrel, V.; Murat, C., Thiele, A. (2014). Recent advances in robust optimization: An overview. European Journal of Operational Research. 471-483. Solomatine, D.P. (2012). Robust Optimization and Probabilistic Analysis of Robustness (ROPAR). http://www.unesco-ihe.org/hi/sol/papers/ ROPAR.pdf.

Impervious surfaces and sewer pipe effects on stormwater runoff temperature

NASA Astrophysics Data System (ADS)

Sabouri, F.; Gharabaghi, B.; Mahboubi, A. A.; McBean, E. A.

2013-10-01

The warming effect of the impervious surfaces in urban catchment areas and the cooling effect of underground storm sewer pipes on stormwater runoff temperature are assessed. Four urban residential catchment areas in the Cities of Guelph and Kitchener, Ontario, Canada were evaluated using a combination of runoff monitoring and modelling. The stormwater level and water temperature were monitored at 10 min interval at the inlet of the stormwater management ponds for three summers 2009, 2010 and 2011. The warming effect of the ponds is also studied, however discussed in detail in a separate paper. An artificial neural network (ANN) model for stormwater temperature was trained and validated using monitoring data. Stormwater runoff temperature was most sensitive to event mean temperature of the rainfall (EMTR) with a normalized sensitivity coefficient (Sn) of 1.257. Subsequent levels of sensitivity corresponded to the longest sewer pipe length (LPL), maximum rainfall intensity (MI), percent impervious cover (IMP), rainfall depth (R), initial asphalt temperature (AspT), pipe network density (PND), and rainfall duration (D), respectively. Percent impervious cover of the catchment area (IMP) was the key parameter that represented the warming effect of the paved surfaces; sensitivity analysis showed IMP increase from 20% to 50% resulted in runoff temperature increase by 3 °C. The longest storm sewer pipe length (LPL) and the storm sewer pipe network density (PND) are the two key parameters that control the cooling effect of the underground sewer system; sensitivity analysis showed LPL increase from 345 to 966 m, resulted in runoff temperature drop by 2.5 °C.

Occurrence of alkylphenolic substances in a Great Lakes coastal marsh, Cootes Paradise, ON, Canada.

PubMed

Mayer, T; Bennie, D; Rosa, F; Rekas, G; Palabrica, V; Schachtschneider, J

2007-06-01

Occurrence and fate of alkylphenols (APs), known endocrine disruptors, were investigated in a Great Lakes coastal wetland, Cootes Paradise, ON. The wetland, which receives discharges from a Wastewater Treatment Plant (WTP) and several Combined Sewer Overflows (CSOs), is an important spawning ground for fish and crucial habitat for other fauna. Elevated concentrations of nonylphenol ethoxylates (NPEs) and their degradation product nonylphenol (NP) were found in water and sediment samples near the sources. Since transfer of APs through the food chain is of concern, we compared their concentrations in invertebrates from clean and contaminated sites. The results reveal transfer of alkylphenolics from sediments to biota and their accumulation in the invertebrate tissue, particularly the highly hydrophobic 4-NP, whose concentrations ranged from 1.9 to 6.3 microg g(-1). To our knowledge, this is the first study to evaluate AP concentrations in tissue of benthic invertebrates under real environmental conditions.

PAHs and PCBs deposited in surficial sediments along a rural to urban transect in a mid-Atlantic coastal river basin (USA).

PubMed

Foster, Gregory D; Cui, Vickie

2008-10-01

PAHs and PCBs were measured in river sediments along a 226 km longitudinal transect that spanned rural to urban land use settings through Valley and Ridge, Piedmont Plateau and Coastal Plain physiographic provinces in the Potomac River basin (mid-Atlantic USA). A gradient in PAH concentrations was found in river bed sediments along the upstream transect in the Potomac and Shenandoah Rivers that correlated with population densities in the nearby sub-basins. Sediment PAH concentrations halved per each approximately 40 km of transect distance upstream (i.e., the half-concentration distance) from the urban center (Washington, DC) of the Potomac River basin in direct proportion to population density. The PAH molecular composition was consistent across all geologic provinces, revealing a dominant pyrogenic source. Fluoranthene to perylene ratios served as useful markers for urban inputs, with a ratio > 2.4 observed in sediments near urban structures such as roadways, bridges and sewer outfalls. PCBs in sediments were not well correlated with population densities along the river basin transect, but the highest concentrations were found in the urban Coastal Plain region near Washington, DC and in the Shenandoah River near a known industrial Superfund site. PAHs were moderately correlated with sediment total organic carbon (TOC) in the Shenandoah River and Coastal Plain Potomac River regions, but TOC was poorly correlated with PCB concentrations throughout the entire basin. Although both PAHs and PCBs are widely recognized as urban-derived contaminants, their concentration profiles and geochemistry in river sediments were uniquely different throughout the upper Potomac River basin.

Historic brownfields and industrial activity in Kingston, Ontario: assessing potential contributions to mercury contamination in sediment of the Cataraqui River.

PubMed

Manion, N C; Campbell, L; Rutter, A

2010-04-01

The waterfront of historic Kingston, Ontario (pop: 113,000) has been used for industrial activities for over a century. More than 40 industries have existed within the inner harbour, and while many of these industries are no longer present, the properties that they operated on remain as potential sources of persistent contamination to the present day, including mercury. To assess the extent and distribution of total mercury (THg) contamination, 21 sediment cores as well as pore water samples were collected within the inner harbour of Kingston. The spatial distribution of THg in the surface sediment is not homogenous; with concentrations in the surface sediment along the southwestern shoreline, adjacent to the former industrial properties, are significantly greater (p<0.01) than the rest of the inner harbour, and were above the Federal severe effect limit (>2000 microg/kg;) guideline for sediment. MeHg was detected in some sediment cores, and was found to have a significant, positive correlation with [THg] in the surface sediment (0-5 cm). THg was not found in storm sewer discharges, but was detected in terrestrial soil near the Kingston Rowing Club at a concentration of more than 4000 microg/kg. Significant [THg] was detected in runoff draining from contaminated shoreline soils, indicating that erosion from terrestrial sources may be an ongoing source of Hg to the sediment. It can be concluded that there is an increased risk over time to surrounding ecosystems where properties with historical contamination are not remediated until they are developed. (c) 2010 Elsevier B.V. All rights reserved.

Stormwater Pollution Prevention Plan (SWPPP) for Coal Storage Area Stabilization Project

DOE Office of Scientific and Technical Information (OSTI.GOV)

Project and Design Engineering

2011-03-01

The scope of this project is to stabilize the abandoned coal storage area and redirect the storm water runoff from sanitary sewer system to the storm drain system. Currently, the existing storm water runoff is directed to a perimeter concrete drainage swale and collected in a containment basin. The collected water is then pumped to a treatment facility and after treatment, is discharged to the Y-12 sanitary sewer system. The existing drainage swale and collection basin along with silt fencing will be used during aggregate placement and grading to provide erosion and sediment control. Inlet protection will also be installedmore » around existing structures during the storm water diversion construction. This project scope will include the installation of a non-woven geotextile fabric and compacted mineral aggregate base (paving optional) to stabilize the site. The geotextile specifications are provided on the vendor cut sheets in Appendix B. The installation of a storm water collection/retention area will also be installed on the southern side of the site in accordance with EPA Technical Guidance on Implementing the Stormwater Runoff Requirements for federal Projects under Section 438 of the Energy Independence and Security Act. The total area to be disturbed is approximately 2.5 acres. The order of activities for this Stormwater Pollution Prevention Plan (SWPPP) will be: (1) post notice of coverage (NOC) in a prominent display near entrance of the site; (2) install rain gauge on site or contact Y-12 Plant Shift Superintendent daily for Met tower rain gauge readings; (3) install stabilized construction exit on site; (4) install silt fencing along perimeter as indicated on the attached site plan; (5) regrade site; (6) install geotextile fabric and compacted mineral aggregate base; (7) install catch basin inlet protection where required; (8) excavate and lower existing catch basin tops, re-grade and asphalt to drain; and (9) when all disturbed areas are re-stabilized, remove silt fencing and any other temporary erosion control.« less

Using data from monitoring combined sewer overflows to assess, improve, and maintain combined sewer systems.

PubMed

Montserrat, A; Bosch, Ll; Kiser, M A; Poch, M; Corominas, Ll

2015-02-01

Using low-cost sensors, data can be collected on the occurrence and duration of overflows in each combined sewer overflow (CSO) structure in a combined sewer system (CSS). The collection and analysis of real data can be used to assess, improve, and maintain CSSs in order to reduce the number and impact of overflows. The objective of this study was to develop a methodology to evaluate the performance of CSSs using low-cost monitoring. This methodology includes (1) assessing the capacity of a CSS using overflow duration and rain volume data, (2) characterizing the performance of CSO structures with statistics, (3) evaluating the compliance of a CSS with government guidelines, and (4) generating decision tree models to provide support to managers for making decisions about system maintenance. The methodology is demonstrated with a case study of a CSS in La Garriga, Spain. The rain volume breaking point from which CSO structures started to overflow ranged from 0.6 mm to 2.8 mm. The structures with the best and worst performance in terms of overflow (overflow probability, order, duration and CSO ranking) were characterized. Most of the obtained decision trees to predict overflows from rain data had accuracies ranging from 70% to 83%. The results obtained from the proposed methodology can greatly support managers and engineers dealing with real-world problems, improvements, and maintenance of CSSs. Copyright © 2014 Elsevier B.V. All rights reserved.

Predicting combined sewer overflows chamber depth using artificial neural networks with rainfall radar data.

PubMed

Mounce, S R; Shepherd, W; Sailor, G; Shucksmith, J; Saul, A J

2014-01-01

Combined sewer overflows (CSOs) represent a common feature in combined urban drainage systems and are used to discharge excess water to the environment during heavy storms. To better understand the performance of CSOs, the UK water industry has installed a large number of monitoring systems that provide data for these assets. This paper presents research into the prediction of the hydraulic performance of CSOs using artificial neural networks (ANN) as an alternative to hydraulic models. Previous work has explored using an ANN model for the prediction of chamber depth using time series for depth and rain gauge data. Rainfall intensity data that can be provided by rainfall radar devices can be used to improve on this approach. Results are presented using real data from a CSO for a catchment in the North of England, UK. An ANN model trained with the pseudo-inverse rule was shown to be capable of predicting CSO depth with less than 5% error for predictions more than 1 hour ahead for unseen data. Such predictive approaches are important to the future management of combined sewer systems.

Methodology for Identifying and Quantifying Metal Pollutant Sources in Storm Water Runoff

DTIC Science & Technology

2015-02-01

sanitary sewer are not viable options. In addition, visual inspections of the drainage areas have been insufficient in identifying and quantifying the...diverting the runoff into the sanitary sewer system, but the cost could exceed millions of dollars. Instead of capturing and treating all stormwater...Unknown Appears only if Building Siding is “metal” Roof Material roof_mat_d Built Up, Metal Panel, Asphalt, Fabric, Clay , Slate, Wood, Other

Effects of wastewater and combined sewer overflows on water quality in the Blue River basin, Kansas City, Missouri and Kansas, July 1998-October 2000

USGS Publications Warehouse

Wilkison, Donald H.; Armstrong, Daniel J.; Blevins, Dale W.

2002-01-01

Samples were collected from 16 base-flow events and a minimum of 10 stormflow events between July 1998 and October 2000 to characterize the effects of wastewater and combined sewer overflows on water quality in the Blue River Basin, Kansas City, Missouri and Kansas. Waterquality effects were determined by analysis of nutrients, chloride, chemical and biochemical oxygen demand, and suspended sediment samples from three streams (Blue River, Brush Creek, and Indian Creek) in the basin as well as the determination of a suite of compounds known to be indicative of wastewater including antioxidants, caffeine, detergent metabolites, antimicrobials, and selected over-the-counter and prescription pharmaceuticals. Constituent loads were determined for both hydrologic regimes and a measure of the relative water-quality impact of selected stream reaches on the Blue River and Brush Creek was developed. Genetic fingerprint patterns of Escherichia coli bacteria from selected stream samples were compared to a data base of knownsource patterns to determine possible sources of bacteria. Water quality in the basin was affected by wastewater during both base flows and stormflows; however, there were two distinct sources that contributed to these effects. In the Blue River and Indian Creek, the nearly continuous discharge of treated wastewater effluent was the primary source of nutrients, wastewater indicator compounds, and pharmaceutical compounds detected in stream samples. Wastewater inputs into Brush Creek were largely the result of intermittent stormflow events that triggered the overflow of combined storm and sanitary sewers, and the subsequent discharge of untreated wastewater into the creek. A portion of the sediment, organic matter, and associated constituents from these events were trapped by a series of impoundments constructed along Brush Creek where they likely continued to affect water quality during base flow. Concentrations and loads of most wastewater constituents in the Blue River and Indian Creek were significantly greater than in Brush Creek, especially during base flow. However, wastewater indicator compound concentrations were sometimes greater in some Brush Creek stormflow samples. Selected stream reaches along the mid-portion of Brush Creek showed higher effects relative to other sites, primarily because these sites were in impounded reaches with the greatest density of wastewater inputs, or had relatively small drainage areas.

Design flow factors for sewerage systems in small arid communities.

PubMed

Imam, Emad H; Elnakar, Haitham Y

2014-09-01

Reliable estimation of sewage flow rates is essential for the proper design of sewers, pumping stations, and treatment plants. The design of the various components of the sewerage system should be based on the most critical flow rates with a focus on extremely low and peak flow rates that would be sustained for a duration related to the acceptable limits of behavior of the components under consideration. The extreme flow conditions and to what extent they differ from the average values are closely related to the size of the community or network, and the socioeconomic conditions. A single pumping station is usually sufficient to pump flow from small community in either flat or non-undulating topography. Therefore, the hydraulic loading on the wastewater treatment plant (WWTP) results from the pumped flow from the pumping station rather than the trunk sewer flow. The intermittent operation of the pumping units further accentuates the sewage hydrograph in the final trunk sewer. Accordingly, the design flow for the various components of the WWTP should be determined based on their relevant flow factors. In this study, analysis of one representative small community out of five monitored small communities in Egypt and the Kingdom of Saudi Arabia is presented. Pumped sewage flow rates were measured and the sewer incoming flows were hydraulically derived. The hourly and daily sewer and pumped flow records were analyzed to derive the relationship between the flow factors that would be sustained for various durations (instantaneously, 1 h, 2 h, etc.) and their probability of non-exceedance. The resulting peaking factors with a consideration for their sustained flow duration and specified probability would permit the design of the various components of the treatment plant using more accurate critical flows.

Design flow factors for sewerage systems in small arid communities

PubMed Central

Imam, Emad H.; Elnakar, Haitham Y.

2013-01-01

Reliable estimation of sewage flow rates is essential for the proper design of sewers, pumping stations, and treatment plants. The design of the various components of the sewerage system should be based on the most critical flow rates with a focus on extremely low and peak flow rates that would be sustained for a duration related to the acceptable limits of behavior of the components under consideration. The extreme flow conditions and to what extent they differ from the average values are closely related to the size of the community or network, and the socioeconomic conditions. A single pumping station is usually sufficient to pump flow from small community in either flat or non-undulating topography. Therefore, the hydraulic loading on the wastewater treatment plant (WWTP) results from the pumped flow from the pumping station rather than the trunk sewer flow. The intermittent operation of the pumping units further accentuates the sewage hydrograph in the final trunk sewer. Accordingly, the design flow for the various components of the WWTP should be determined based on their relevant flow factors. In this study, analysis of one representative small community out of five monitored small communities in Egypt and the Kingdom of Saudi Arabia is presented. Pumped sewage flow rates were measured and the sewer incoming flows were hydraulically derived. The hourly and daily sewer and pumped flow records were analyzed to derive the relationship between the flow factors that would be sustained for various durations (instantaneously, 1 h, 2 h, etc.) and their probability of non-exceedance. The resulting peaking factors with a consideration for their sustained flow duration and specified probability would permit the design of the various components of the treatment plant using more accurate critical flows. PMID:25685521

Bacteriophage ecology in a small community sewer system related to their indicative role in sewage pollution of drinking water.

PubMed

Gino, Efrat; Starosvetsky, Jeana; Armon, Robert

2007-10-01

In view of various studies looking for the merit of coliphages as indicators of water pollution with viruses originating from faecal material, a small agricultural community (population of approximately 1500 inhabitants of all ages, 2-3 km from Haifa) was selected in order to understand these bacteriophage ecology (F-RNA and somatic coliphages) in its sewer and oxidation pond system. Along the sewer lines, it was possible to isolate constantly both bacteriophage types (F-RNA and somatic coliphages) at 10(2)-10(4) plaque-forming units (pfu) ml(-1). The average numbers of somatic and F-RNA phages isolated from oxidation pond were 10(3)-10(4) pfu ml(-1); however, somatic coliphages were undetectable for several months (April-August). Significant high correlation (0.944 < R(2) < 0.99) was found between increased anionic detergent concentrations and F-RNA coliphage numbers. Infants less than 1 year old excreted both phage types and few only F-RNA coliphages (at high numbers > 10(5) pfu g(-1)) for up to 1 year. The excretion of F-RNA coliphages was highly linked to Escherichia coli F(+) harborage in the intestinal track as found in their faecal content. Finally, three bacterial hosts E. coli F(+), F(-) and CN(13) tested for survivability in sewage filtrate revealed that E. coli F(+) had the highest survivability under these conditions. Presence of somatic and F male-specific phages in sewer lines of a small community are influenced by several factors such as: anionic detergents, nutrients, temperature, source (mainly infants), shedding and survival capability of the host strain. Better understanding of coliphages ecology in sewer systems can enhance our evaluation of these proposed indicator/index microorganisms used in tracking environmental pollution of water, soil and crop contamination with faecal material containing enteric viruses.

Superfund record of decision (EPA Region 2): Love Canal, Niagara Falls, New York, October 1987. Second remedial action

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

The Love Canal site is located in the southeast corner of the city of Niagara Falls and is approximately one-quarter mile north of the Niagara River. The canal was one of two initial excavations designed to provide inexpensive hydroelectric power for industrial development around the turn of the 20th century. Hooker Chemicals and Plastics Corporation (Hooker), now Occidental Chemical Corporation, disposed of over 21,000 tons of chemical wastes, including dioxin-tainted trichlorophenols, into Love Canal between 1942 and 1953. In the mid to late 1970s, continued periods of high precipitation contributed to water accumulation in the disposal area causing chemically-contaminated leachatemore » to be carried to the surface and into contact with residential-basement foundations. Also, dioxin and other contaminants migrated from Love Canal to the sewers which have outfalls to nearby creeks. The remedial program at Love Canal has been extensive and has occurred in two phases. Approximately 30,400 cu yd - 40,900 cu yd of creek and sewer sediments are contaminated with 2,3,7,8-tetrachlorodibenzo-p-dioxin, commonly referred to as dioxin.« less

Contaminant transport pathways between urban sewer networks and water supply wells

USDA-ARS?s Scientific Manuscript database

Water supply wells and sanitary sewers are critical components of urban infrastructure, but sewer leakage threatens the quality of groundwater in sewered areas. Previous work by our group has documented the presence of human enteric viruses in deep public supply wells. Our current research uses such...

Evidence of a sewer vapor transport pathway at the USEPA vapor intrusion research duplex

EPA Science Inventory

The role of sewer lines as preferential pathways for vapor intrusion is poorly understood. Although the importance of sewer lines for volatile organic compound (VOC) transport has been documented at a small number of sites with vapor intrusion, sewer lines are not routinely sampl...

DSM-flux: A new technology for reliable Combined Sewer Overflow discharge monitoring with low uncertainties.

PubMed

Maté Marín, Ainhoa; Rivière, Nicolas; Lipeme Kouyi, Gislain

2018-06-01

In the past ten years, governments from the European Union have been encouraged to collect volume and quality data for all the effluent overflows from separated stormwater and combined sewer systems that result in a significant environmental impact on receiving water bodies. Methods to monitor and control these flows require improvements, particularly for complex Combined Sewer Overflow (CSO) structures. The DSM-flux (Device for Stormwater and combined sewer flows Monitoring and the control of pollutant fluxes) is a new pre-designed and pre-calibrated channel that provides appropriate hydraulic conditions suitable for measurement of overflow rates and volumes by means of one water level gauge. In this paper, a stage-discharge relation for the DSM-flux is obtained experimentally and validated for multiple inflow hydraulic configurations. Uncertainties in CSO discharges and volumes are estimated within the Guide to the expression of Uncertainty in Measurement (GUM) framework. Whatever the upstream hydraulic conditions are, relative uncertainties are lower than 15% and 2% for the investigated discharges and volumes, respectively. Copyright © 2018 Elsevier Ltd. All rights reserved.

Impact of Redevelopment Projects on Waste Water Infrastructure

NASA Astrophysics Data System (ADS)

Bhave, Prashant; Rahate, Sarvesh

2018-05-01

In the last few decades there has been a tremendous increase in urban population globally. Metropolitan cities in India are experiencing rapid change in their population due to migration from rural to urban areas. Due to limited land Mumbai city is experiencing vertical growth in the form of redevelopment projects, signifying a change in population density. Wastewater collection systems greatly contribute to the cost of the overall municipal sewerage system. Present study is an attempt to understand the impact of the redevelopment activities on the wastewater infrastructure. Existing sewerage network of an urban area in Central Mumbai was redesigned and analysed for four different planning scenarios with Bentley's SewerGEM. Results have shown significant change in diameters of the conduits within the sewer network, thus making it inefficient by 13, 19, 31 and 42% with each changing scenario. The results and analysis derived from the study are significant with respect to the urban town planners, developing solutions in alleviating the rising problem of sewer overflows and the economic impact being caused.

Development of a semi-automated model identification and calibration tool for conceptual modelling of sewer systems.

PubMed

Wolfs, Vincent; Villazon, Mauricio Florencio; Willems, Patrick

2013-01-01

Applications such as real-time control, uncertainty analysis and optimization require an extensive number of model iterations. Full hydrodynamic sewer models are not sufficient for these applications due to the excessive computation time. Simplifications are consequently required. A lumped conceptual modelling approach results in a much faster calculation. The process of identifying and calibrating the conceptual model structure could, however, be time-consuming. Moreover, many conceptual models lack accuracy, or do not account for backwater effects. To overcome these problems, a modelling methodology was developed which is suited for semi-automatic calibration. The methodology is tested for the sewer system of the city of Geel in the Grote Nete river basin in Belgium, using both synthetic design storm events and long time series of rainfall input. A MATLAB/Simulink(®) tool was developed to guide the modeller through the step-wise model construction, reducing significantly the time required for the conceptual modelling process.

Impact of toxic chemicals on local wastewater treatment plant and the environment

NASA Astrophysics Data System (ADS)

Bennett, Gary F.

1989-05-01

Because toxic chemicals being discharged to sewers were simultaneously interfering with wastewater treatment processes of municipal, biological treatment plants and were passing through these plants to negatively impact the bodies of water to which these plants were discharging, the U.S. Environmental Protection Agency issued regulations governing industrial discharges to municipal sewers. These “Pretreatment Regulations” limit industrial discharges to municipal sewers of heavy metals, oil and grease, acids and bases, and toxic organic chemicals. This paper discusses the evolution of these regulations, the basis for them, the types of regulations (categorical and local), and the rationale for their promulgation based on the impacts of toxics chemicals on the treatment plant and receiving system. Finally, the expected results of these regulations in reducing industrial discharges of toxic chemicals is discussed.

Development of an optical fiber flow velocity sensor.

PubMed

Harada, Toshio; Kamoto, Kenji; Abe, Kyutaro; Izumo, Masaki

2009-01-01

A new optical fiber flow velocity sensor was developed by using an optical fiber information network system in sewer drainage pipes. The optical fiber flow velocity sensor operates without electric power, and the signals from the sensor can be transmitted over a long distance through the telecommunication system in the optical fiber network. Field tests were conducted to check the performance of the sensor in conduits in the pumping station and sewage pond managed by the Tokyo Metropolitan Government. Test results confirmed that the velocity sensor can be used for more than six months without any trouble even in sewer drainage pipes.

Optimise inlet condition and design parameters of a new sewer overflow screening device using numerical model.

PubMed

Aziz, M A; Imteaz, M A; Huda, Nazmul; Naser, J

2014-01-01

After heavy rainfall, sewer overflow spills to receiving water bodies cause serious concern for the environment, aesthetics and public health. To overcome these problems this study investigated a new self-cleansing sewer overflow screening device. The device has a sewer overflow chamber, a rectangular tank and a slotted ogee weir to capture the gross pollutants. To design an efficient screening device a numerical computational fluid dynamic (CFD) model was used. A plausibility check of the CFD model was done using a one-dimensional analytical model. Results showed that an inlet parallel to the weir ensured better self-cleansing than an inlet perpendicular to the weir. Perforations should be at the bottom of the weir to get increased velocity and shear stress to create a favourable self-cleaning effect of the screening device. Increasing inlet length from 0.3 to 1.5 m reduced wave reflection up to 10%, which increased flow uniformity downstream and improved self-cleansing effect. The orientation of the ogee weir with the rectangular tank was found most uniform with a 1:3 (horizontal:vertical) slope. These results will help to maximise functional efficiency of the new sewer overflow screening device. Otherwise it would be too expensive to alter after installation and at times difficult to customise accordingly to existing urban drainage systems.

Constructing and dismantling frameworks of disease etiology: the rise and fall of sewer gas in America, 1870-1910.

PubMed Central

An, Perry G.

2004-01-01

For roughly forty years, from 1870 to 1910, Americans recognized and feared gases emanating from sewers, believing that they were responsible for causing an array of diseases. Fears of sewer gas arose from deeper anxieties toward contact with decomposing organic matter and the vapors emitted from such refuse. These anxieties were exacerbated by the construction of sewers across the country during the mid-to-late-nineteenth century, which concentrated waste emanations and connected homes to one another. The result was the birth of sewer gas and the attribution of sickness and death to it, as well as the development of a host of plumbing devices and, especially, bathroom fixtures, to combat sewer gas. The rise of the germ theory, laboratory science, and belief in disease specificity, however, transformed the threat of sewer gas, eventually replacing it (and the larger fear of miasmas) with the threat of germs. The germ theory framework, by 1910, proved more suitable than the sewer gas framework in explaining disease causation; it is this suitability that often shapes the relationship between science and society. PMID:15829149

Online dissolved methane and total dissolved sulfide measurement in sewers.

PubMed

Liu, Yiwen; Sharma, Keshab R; Fluggen, Markus; O'Halloran, Kelly; Murthy, Sudhir; Yuan, Zhiguo

2015-01-01

Recent studies using short-term manual sampling of sewage followed by off-line laboratory gas chromatography (GC) measurement have shown that a substantial amount of dissolved methane is produced in sewer systems. However, only limited data has been acquired to date due to the low frequency and short span of this method, which cannot capture the dynamic variations of in-sewer dissolved methane concentrations. In this study, a newly developed online measuring device was used to monitor dissolved methane concentrations at the end of a rising main sewer network, over two periods of three weeks each, in summer and early winter, respectively. This device uses an online gas-phase methane sensor to measure methane under equilibrium conditions after being stripped from the sewage. The data are then converted to liquid-phase methane concentrations according to Henry's Law. The detection limit and range are suitable for sewer application and can be adjusted by varying the ratio of liquid-to-gas phase volume settings. The measurement presented good linearity (R² > 0.95) during field application, when compared to off-line measurements. The overall data set showed a wide variation in dissolved methane concentration of 5-15 mg/L in summer and 3.5-12 mg/L in winter, resulting in a significant average daily production of 24.6 and 19.0 kg-CH₄/d, respectively, from the network with a daily average sewage flow of 2840 m³/day. The dissolved methane concentration demonstrated a clear diurnal pattern coinciding with flow and sulfide fluctuation, implying a relationship with the wastewater hydraulic retention time (HRT). The total dissolved sulfide (TDS) concentration in sewers can be determined simultaneously with the same principle.

Rain fall data for the design of sewer pipe systems

NASA Astrophysics Data System (ADS)

Arnell, V.

1982-03-01

A comparison of designs of sewer pipes for different types of rainfall data is presented. Local coefficients were evaluated from an 18-year historical rainfall record for the following design storms: The Average-Intensity-Duration Design Storm, The Chicago Design Storm, The Sifalda Design Storm, The Illinois State Water Survey Design Storm, and The Flood Studies Report Design Storm. Historical rainfalls as well as the above design storms were used for the calculations of peak-flow values.

Assessing the Role of Sewers and Atmospheric Deposition as Nitrate Contamination Sources to Urban Surface Waters using Stable Nitrate Isotopes

NASA Astrophysics Data System (ADS)

Sikora, M. T.; Elliott, E. M.

2009-12-01

Excess nitrate (NO3-) contributes to the overall degraded quality of streams in many urban areas. These systems are often dominated by impervious surfaces and storm sewers that can route atmospherically deposited nitrogen, from both wet and dry deposition, to waterways. Moreover, in densely populated watersheds there is the potential for interaction between urban waterways and sewer systems. The affects of accumulated nitrate in riverine and estuary systems include low dissolved oxygen, loss of species diversity, increased mortality of aquatic species, and general eutrophication of the waterbody. However, the dynamics of nitrate pollution from each source and it’s affect on urban waterways is poorly constrained. The isotopes of nitrogen and oxygen in nitrate have been proven effective in helping to distinguish contamination sources to ground and surface waters. In order to improve our understanding of urban nitrate pollution sources and dynamics, we examined nitrate isotopes (δ15N and δ18O) in base- and stormflow samples collected over a two-year period from a restored urban stream in Pittsburgh, Pennsylvania (USA). Nine Mile Run drains a 1,600 hectare urban watershed characterized by 38% impervious surface cover. Prior work has documented high nitrate export from the watershed (~19 kg NO3- ha-1 yr-1). Potential nitrate sources to the watershed include observed sewer overflows draining directly to the stream, as well as atmospheric deposition (~23 kg NO3- ha-1 yr-1). In this and other urban systems with high percentages of impervious surfaces, there is likely minimal input from nitrate derived from soil or fertilizer. In this presentation, we examine spatial and temporal patterns in nitrate isotopic composition collected at five locations along Nine Mile Run characterized by both sanitary and combined-sewer cross-connections. Preliminary isotopic analysis of low-flow winter streamwater samples suggest nitrate export from Nine Mile Run is primarily influenced by inputs of human waste despite high rates of atmospheric nitrate deposition. Further isotopic analysis of nitrate will examine seasonal variations in nitrate sources; compare nitrate dynamics and sources during low- versus high-flows, and the influence of interannual climatic variability on nitrate export.

Consequential environmental and economic life cycle assessment of green and gray stormwater infrastructures for combined sewer systems.

PubMed

Wang, Ranran; Eckelman, Matthew J; Zimmerman, Julie B

2013-10-01

A consequential life cycle assessment (LCA) is conducted to evaluate the trade-offs between water quality improvements and the incremental climate, resource, and economic costs of implementing green (bioretention basin, green roof, and permeable pavement) versus gray (municipal separate stormwater sewer systems, MS4) alternatives of stormwater infrastructure expansions against a baseline combined sewer system with combined sewer overflows in a typical Northeast US watershed for typical, dry, and wet years. Results show that bioretention basins can achieve water quality improvement goals (e.g., mitigating freshwater eutrophication) for the least climate and economic costs of 61 kg CO2 eq. and $98 per kg P eq. reduction, respectively. MS4 demonstrates the minimum life cycle fossil energy use of 42 kg oil eq. per kg P eq. reduction. When integrated with the expansion in stormwater infrastructure, implementation of advanced wastewater treatment processes can further reduce the impact of stormwater runoff on aquatic environment at a minimal environmental cost (77 kg CO2 eq. per kg P eq. reduction), which provides support and valuable insights for the further development of integrated management of stormwater and wastewater. The consideration of critical model parameters (i.e., precipitation intensity, land imperviousness, and infrastructure life expectancy) highlighted the importance and implications of varying local conditions and infrastructure characteristics on the costs and benefits of stormwater management. Of particular note is that the impact of MS4 on the local aquatic environment is highly dependent on local runoff quality indicating that a combined system of green infrastructure prior to MS4 potentially provides a more cost-effective improvement to local water quality.

Contribution of Geographic Information Systems and location models to planning of wastewater systems.

PubMed

Leitão, J P; Matos, J S; Gonçalves, A B; Matos, J L

2005-01-01

This paper presents the contributions of Geographic Information Systems (GIS) and location models towards planning regional wastewater systems (sewers and wastewater treatment plants) serving small agglomerations, i.e. agglomerations with less than 2,000 inhabitants. The main goal was to develop a decision support tool for tracing and locating regional wastewater systems. The main results of the model are expressed in terms of number, capacity and location of Wastewater Treatment Plants (WWTP) and the length of main sewers. The decision process concerning the location and capacity of wastewater systems has a number of parameters that can be optimized. These parameters include the total sewer length and number, capacity and location of WWTP. The optimization of parameters should lead to the minimization of construction and operation costs of the integrated system. Location models have been considered as tools for decision support, mainly when a geo-referenced database can be used. In these cases, the GIS may represent an important role for the analysis of data and results especially in the preliminary stage of planning and design. After selecting the spatial location model and the heuristics, two greedy algorithms were implemented in Visual Basic for Applications on the ArcGIS software environment. To illustrate the application of these algorithms a case study was developed, in a rural area located in the central part of Portugal.

Localization of groundwater infiltration in the combined sewers of Brussels by stable isotopes measurements (δ18O, δD) by Cavity Ring Down Spectroscopy.

NASA Astrophysics Data System (ADS)

De Bondt, Kevin; Claeys, Philippe

2014-05-01

In the last 20 years research has been conducted to quantify the infiltration of groundwater into the sewers. This groundwater, called parasitic water, increases the volume of waste-water to be treated and consequently the cost of this treatment. Moreover, in the case of combined sewer systems, the parasitic water also limits the sewer capacity and indirectly increases the risks of combined sewer overflows and floods. The infiltration of groundwater occurs trough cracks, sewer collapses and from direct connections with old springs. Different methods quantify the intrusion of parasitic water. Among these, the use of the stable isotopes of water (δ18O & δD) shows good result in catchments or cities close to Mountainous regions (example from Lyon, Zurich), where isotopic signals vary significantly because of continental and altitude effects. However many cities, such as Brussels, are located in more oceanic settings and theoretically offer less potential for the application of the stable isotopes method. In the case of Brussels, river-water from the Meuse is used to produce domestic-water. The catchment of this river extends into the Ardennes, which are affected by slightly different climatic conditions. δ18O & δD analyzes of groundwater from the main aquifer (Ledo-Paniselian-Brusselian) and domestic-water from the Callois reservoir fed by the Meuse River show sufficient isotopic differences in the south of Brussels, but only during the summer. The discrimination potential is better with δD than with δ18O. The improvement of δD measurements (precision, costs,...) brought by Cavity Ring Down Spectroscopy largely contributes to the potential of using stable isotopes method to trace water in Brussels. The first campaigns in the sewers also show a little enrichment (in heavy isotopes) of the waste-water in comparison with the reservoir waters and tap waters. This increases the potential of the method but constrains the sampling to pure waste-water in sewer segments without infiltration generally localized upstream. Anyway, it is in the localization of parasitic water entrance from upstream to downstream that the stable isotopes method is the most powerful. Other methods (e.g. minimum night flow,...) are available at the treatment plants or at flow measurement stations downstream but will not be able to localize parasitic water intrusion towards old springs.

NPDES Stormwater Program

EPA Pesticide Factsheets

The National Pollutant Discharge Elimination System (NPDES) stormwater program regulates some stormwater discharges from three potential sources: municipal separate storm sewer systems (MS4s), construction activities, and industrial activities.

Cesium and strontium loads into a combined sewer system from rainwater runoff.

PubMed

Kamei-Ishikawa, Nao; Yoshida, Daiki; Ito, Ayumi; Umita, Teruyuki

2016-12-01

In this study, combined sewage samples were taken with time in several rain events and sanitary sewage samples were taken with time in dry weather to calculate Cs and Sr loads to sewers from rainwater runoff. Cs and Sr in rainwater were present as particulate forms at first flush and the particulate Cs and Sr were mainly bound with inorganic suspended solids such as clay minerals in combined sewage samples. In addition, multiple linear regression analysis showed Cs and Sr loads from rainwater runoff could be estimated by the total amount of rainfall and antecedent dry weather days. The variation of the Sr load from rainwater to sewers was more sensitive to total amount of rainfall and antecedent dry weather days than that of the Cs load. Copyright © 2016 Elsevier Ltd. All rights reserved.

Reducing pathogens in combined sewer overflows using ozonation or UV irradiation.

PubMed

Tondera, Katharina; Klaer, Kassandra; Gebhardt, Jens; Wingender, Jost; Koch, Christoph; Horstkott, Marina; Strathmann, Martin; Jurzik, Lars; Hamza, Ibrahim Ahmed; Pinnekamp, Johannes

2015-11-01

Fecal contamination of water resources is a major public health concern in densely populated areas since these water bodies are used for drinking water production or recreational purposes. A main source of this contamination originates from combined sewer overflows (CSOs) in regions with combined sewer systems. Thus, the treatment of CSO discharges is urgent. In this study, we explored whether ozonation or UV irradiation can efficiently reduce pathogenic bacteria, viruses, and protozoan parasites in CSOs. Experiments were carried out in parallel settings at the outflow of a stormwater settling tank in the Ruhr area, Germany. The results showed that both techniques reduce most hygienically relevant bacteria, parasites and viruses. Under the conditions tested, ozonation yielded lower outflow values for the majority of the tested parameters. Copyright © 2015 Elsevier GmbH. All rights reserved.

Identifying the best locations to install flow control devices in sewer networks to enable in-sewer storage

NASA Astrophysics Data System (ADS)

Leitão, J. P.; Carbajal, J. P.; Rieckermann, J.; Simões, N. E.; Sá Marques, A.; de Sousa, L. M.

2018-01-01

The activation of available in-sewer storage volume has been suggested as a low-cost flood and combined sewer overflow mitigation measure. However, it is currently unknown what the attributes for suitable objective functions to identify the best location for flow control devices are and the impact of those attributes on the results. In this study, we present a novel location model and efficient algorithm to identify the best location(s) to install flow limiters. The model is a screening tool that does not require hydraulic simulations but rather considers steady state instead of simplistic static flow conditions. It also maximises in-sewer storage according to different reward functions that also considers the potential impact of flow control device failure. We demonstrate its usefulness on two real sewer networks, for which an in-sewer storage potential of approximately 2,000 m3 and 500 m3 was estimated with five flow control devices installed.

A Random Forest approach to predict the spatial distribution of sediment pollution in an estuarine system

PubMed Central

Kreakie, Betty J.; Cantwell, Mark G.; Nacci, Diane

2017-01-01

Modeling the magnitude and distribution of sediment-bound pollutants in estuaries is often limited by incomplete knowledge of the site and inadequate sample density. To address these modeling limitations, a decision-support tool framework was conceived that predicts sediment contamination from the sub-estuary to broader estuary extent. For this study, a Random Forest (RF) model was implemented to predict the distribution of a model contaminant, triclosan (5-chloro-2-(2,4-dichlorophenoxy)phenol) (TCS), in Narragansett Bay, Rhode Island, USA. TCS is an unregulated contaminant used in many personal care products. The RF explanatory variables were associated with TCS transport and fate (proxies) and direct and indirect environmental entry. The continuous RF TCS concentration predictions were discretized into three levels of contamination (low, medium, and high) for three different quantile thresholds. The RF model explained 63% of the variance with a minimum number of variables. Total organic carbon (TOC) (transport and fate proxy) was a strong predictor of TCS contamination causing a mean squared error increase of 59% when compared to permutations of randomized values of TOC. Additionally, combined sewer overflow discharge (environmental entry) and sand (transport and fate proxy) were strong predictors. The discretization models identified a TCS area of greatest concern in the northern reach of Narragansett Bay (Providence River sub-estuary), which was validated with independent test samples. This decision-support tool performed well at the sub-estuary extent and provided the means to identify areas of concern and prioritize bay-wide sampling. PMID:28738089

Assessing dry weather flow contribution in TSS and COD storm events loads in combined sewer systems.

PubMed

Métadier, M; Bertrand-Krajewski, J L

2011-01-01

Continuous high resolution long term turbidity measurements along with continuous discharge measurements are now recognised as an appropriate technique for the estimation of in sewer total suspended solids (TSS) and Chemical Oxygen Demand (COD) loads during storm events. In the combined system of the Ecully urban catchment (Lyon, France), this technique is implemented since 2003, with more than 200 storm events monitored. This paper presents a method for the estimation of the dry weather (DW) contribution to measured total TSS and COD event loads with special attention devoted to uncertainties assessment. The method accounts for the dynamics of both discharge and turbidity time series at two minutes time step. The study is based on 180 DW days monitored in 2007-2008. Three distinct classes of DW days were evidenced. Variability analysis and quantification showed that no seasonal effect and no trend over the year were detectable. The law of propagation of uncertainties is applicable for uncertainties estimation. The method has then been applied to all measured storm events. This study confirms the interest of long term continuous discharge and turbidity time series in sewer systems, especially in the perspective of wet weather quality modelling.

The Ecology of Acidophilic Microorganisms in the Corroding Concrete Sewer Environment

PubMed Central

Li, Xuan; Kappler, Ulrike; Jiang, Guangming; Bond, Philip L.

2017-01-01

Concrete corrosion is one of the most significant problems affecting valuable sewer infrastructure on a global scale. This problem occurs in the aerobic zone of the sewer, where a layer of surface corrosion develops on the exposed concrete and the surface pH is typically lowered from around 11–10 (pristine concrete) to pH 2–4. Acidophilic microorganisms become established as biofilms within the concrete corrosion layer and enhance the loss of concrete mass. Until recently, the acidophilic community was considered to comprise relatively few species of microorganisms, however, the biodiversity of the corrosion community is now recognized as being extensive and varying from different sewer environmental conditions. The diversity of acidophiles in the corrosion communities includes chemolithoautotrophs, chemolithoheterotrophs, and chemoorganoheterotrophs. The activity of these microorganisms is strongly affected by H2S levels in the sewer gas phase, although CO2, organic matter, and iron in the corrosion layer influence this acidic ecosystem. This paper briefly presents the conditions within the sewer that lead to the development of concrete corrosion in that environment. The review focuses on the acidophilic microorganisms detected in sewer corrosion environments, and then summarizes their proposed functions and physiology, especially in relation to the corrosion process. To our knowledge, this is the first review of acidophilic corrosion microbial communities, in which, the ecology and the environmental conditions (when available) are considered. Ecological studies of sewer corrosion are limited, however, where possible, we summarize the important metabolic functions of the different acidophilic species detected in sewer concrete corrosion layers. It is evident that microbial functions in the acidic sewer corrosion environment can be linked to those occurring in the analogous acidic environments of acid mine drainage and bioleaching. PMID:28473816

The Ecology of Acidophilic Microorganisms in the Corroding Concrete Sewer Environment.

PubMed

Li, Xuan; Kappler, Ulrike; Jiang, Guangming; Bond, Philip L

2017-01-01

Concrete corrosion is one of the most significant problems affecting valuable sewer infrastructure on a global scale. This problem occurs in the aerobic zone of the sewer, where a layer of surface corrosion develops on the exposed concrete and the surface pH is typically lowered from around 11-10 (pristine concrete) to pH 2-4. Acidophilic microorganisms become established as biofilms within the concrete corrosion layer and enhance the loss of concrete mass. Until recently, the acidophilic community was considered to comprise relatively few species of microorganisms, however, the biodiversity of the corrosion community is now recognized as being extensive and varying from different sewer environmental conditions. The diversity of acidophiles in the corrosion communities includes chemolithoautotrophs, chemolithoheterotrophs, and chemoorganoheterotrophs. The activity of these microorganisms is strongly affected by H 2 S levels in the sewer gas phase, although CO 2 , organic matter, and iron in the corrosion layer influence this acidic ecosystem. This paper briefly presents the conditions within the sewer that lead to the development of concrete corrosion in that environment. The review focuses on the acidophilic microorganisms detected in sewer corrosion environments, and then summarizes their proposed functions and physiology, especially in relation to the corrosion process. To our knowledge, this is the first review of acidophilic corrosion microbial communities, in which, the ecology and the environmental conditions (when available) are considered. Ecological studies of sewer corrosion are limited, however, where possible, we summarize the important metabolic functions of the different acidophilic species detected in sewer concrete corrosion layers. It is evident that microbial functions in the acidic sewer corrosion environment can be linked to those occurring in the analogous acidic environments of acid mine drainage and bioleaching.

Prioritizing sewer rehabilitation projects using AHP-PROMETHEE II ranking method.

PubMed

Kessili, Abdelhak; Benmamar, Saadia

2016-01-01

The aim of this paper is to develop a methodology for the prioritization of sewer rehabilitation projects for Algiers (Algeria) sewer networks to support the National Sanitation Office in its challenge to make decisions on prioritization of sewer rehabilitation projects. The methodology applies multiple-criteria decision making. The study includes 47 projects (collectors) and 12 criteria to evaluate them. These criteria represent the different issues considered in the prioritization of the projects, which are structural, hydraulic, environmental, financial, social and technical. The analytic hierarchy process (AHP) is used to determine weights of the criteria and the Preference Ranking Organization Method for Enrichment Evaluations (PROMETHEE II) method is used to obtain the final ranking of the projects. The model was verified using the sewer data of Algiers. The results have shown that the method can be used for prioritizing sewer rehabilitation projects.

Isolation of heavy metal influx to the Cookeville sanitary sewer system and impact on municipal sludge management

DOE Office of Scientific and Technical Information (OSTI.GOV)

George, D.B.; Borup, M.B.; Adams, V.D.

The city of Cookeville, Tennessee, has been experiencing problems with municipal sludge management. Of particular concern was the high concentration of regulated trace metals in the sludge. Primarily, cadmium limited the amount of sludge which was spread on the available cropland in 1985. The purpose of this project was to determine the major sources of heavy metal influx to the city's sanitary sewer system and the potential effects of heavy metals on sludge management. In general, the findings of the study indicate that city enforcement of existing State of Tennessee and city industrial pretreatment requirements will most likely extend themore » useful life of the currently available 388 ha land application sites to as much as ten years for certain sites. Cadmium governed the annual sludge application rates to the agricultural land. One plating industry discharged over 90% of the cadmium, copper, nickel, and zinc mass to the sanitary sewer. In addition, during 1986, the average concentration of most of the trace metals monitored in the municipal sludge deceased from levels reported in 1985.« less

Survival of hydrogen sulfide oxidizing bacteria on corroded concrete surfaces of sewer systems.

PubMed

Jensen, H S; Nielsen, A H; Hvitved-Jacobsen, T; Vollertsen, J

2008-01-01

The activity of hydrogen sulfide oxidizing bacteria within corroded concrete from a sewer manhole was investigated. The bacteria were exposed to hydrogen sulfide starvation for up till 18 months, upon which their hydrogen sulfide oxidizing activity was measured. It was tested whether the observed reduction in biological activity was caused by a biological lag phase or by decay of the bacteria. The results showed that the bacterial activity declined with approximately 40% pr. month during the first two months of hydrogen sulfide starvation. After 2-3 months of starvation, the activity stabilized. Even after 6 months of starvation, exposure to hydrogen sulfide for 6 hours a day on three successive days could restore the bacteriological activity to about 80% of the initial activity. After 12 months of starvation, the activity could, however, not be restored, and after 18 months the biological activity approached zero. The long-term survival aspect of concrete corroding bacteria has implications for predicting hydrogen sulfide corrosion in sewer systems subject to irregular hydrogen sulfide loadings, e.g. as they occur in temperate climates where hydrogen sulfide often is a summer-problem only.

Sewer infiltration/inflow: long-term monitoring based on diurnal variation of pollutant mass flux.

PubMed

Bares, V; Stránský, D; Sýkora, P

2009-01-01

The paper deals with a method for quantification of infiltrating groundwater based on the variation of diurnal pollutant load and continuous water quality and quantity monitoring. Although the method gives us the potential to separate particular components of wastewater hygrograph, several aspects of the method should be discussed. Therefore, the paper investigates the cost-effectiveness, the relevance of pollutant load from surface waters (groundwater) and the influence of measurement time step. These aspects were studied in an experimental catchment of Prague sewer system, Czech Republic, within a three-month period. The results indicate high contribution of parasitic waters on night minimal discharge. Taking into account the uncertainty of the results and time-consuming maintenance of the sensor, the principal advantages of the method are evaluated. The study introduces a promising potential of the discussed measuring concept for quantification of groundwater infiltrating into the sewer system. It is shown that the conventional approach is sufficient and cost-effective even in those catchments, where significant contribution of foul sewage in night minima would have been assumed.

Development and testing of highway storm-sewer flow measurement and recording system

USGS Publications Warehouse

Kilpatrick, F.A.; Kaehrle, W.R.; Hardee, Jack; Cordes, E.H.; Landers, M.N.

1985-01-01

A comprehensive study and development of measuring instruments and techniques for measuring all components of flow in a storm-sewer drainage system was undertaken by the U.S. Geological Survey under the sponsorship of the Federal Highway Administration. The study involved laboratory and field calibration and testing of measuring flumes, pipe insert meters, weirs, electromagnetic velocity meters as well as the development and calibration of pneumatic-bubbler pressure transducer head measuring systems. Tracer-dilution and acoustic flow meter measurements were used in field verification tests. A single micrologger was used to record data from all the above instruments as well as from a tipping-bucket rain gage and also to activate on command the electromagnetic velocity meter and tracer-dilution systems. (Author 's abstract)

Real time control of a combined sewer system using radar-measured precipitation--results of the pilot study.

PubMed

Petruck, A; Holtmeier, E; Redder, A; Teichgräber, B

2003-01-01

Emschergenossenschaft and Lippeverband have developed a method to use radar-measured precipitation as an input for a real-time control of a combined sewer system containing several overflow structures. Two real-time control strategies have been developed and tested, one is solely volume-based, the other is volume and pollution-based. The system has been implemented in a pilot study in Gelsenkirchen, Germany. During the project the system was optimised and is now in constant operation. It was found, that the volume of combined sewage overflow could be reduced by 5 per cent per year. This was also found in simulations carried out in similar catchment areas. Most of the potential of improvement can already be achieved by local pollution-based control strategies.

Modelling the viability of heat recovery from combined sewers.

PubMed

Abdel-Aal, M; Smits, R; Mohamed, M; De Gussem, K; Schellart, A; Tait, S

2014-01-01

Modelling of wastewater temperatures along a sewer pipe using energy balance equations and assuming steady-state conditions was achieved. Modelling error was calculated, by comparing the predicted temperature drop to measured ones in three combined sewers, and was found to have an overall root mean squared error of 0.37 K. Downstream measured wastewater temperature was plotted against modelled values; their line gradients were found to be within the range of 0.9995-1.0012. The ultimate aim of the modelling is to assess the viability of recovering heat from sewer pipes. This is done by evaluating an appropriate location for a heat exchanger within a sewer network that can recover heat without impacting negatively on the downstream wastewater treatment plant (WWTP). Long sewers may prove to be more viable for heat recovery, as heat lost can be reclaimed before wastewater reaching the WWTP.

Simulation of sulfide buildup in wastewater and atmosphere of sewer networks.

PubMed

Nielsen, A H; Yongsiri, C; Hvitved-Jacobsen, T; Vollertsen, J

2005-01-01

A model concept for prediction of sulfide buildup in sewer networks is presented. The model concept is an extension to--and a further development of--the WATS model (Wastewater Aerobic-anaerobic Transformations in Sewers), which has been developed by Hvitved-Jacobsen and co-workers at Aalborg University. In addition to the sulfur cycle, the WATS model simulates changes in dissolved oxygen and carbon fractions of different biodegradability. The sulfur cycle was introduced via six processes: 1. sulfide production taking place in the biofilm covering the permanently wetted sewer walls; 2. biological sulfide oxidation in the permanently wetted biofilm; 3. chemical and biological sulfide oxidation in the water phase; 4. sulfide precipitation with metals present in the wastewater; 5. emission of hydrogen sulfide to the sewer atmosphere and 6. adsorption and oxidation of hydrogen sulfide on the moist sewer walls where concrete corrosion may take place.

City sewer collectors biocorrosion

NASA Astrophysics Data System (ADS)

Ksiażek, Mariusz

2014-12-01

This paper presents the biocorrosion of city sewer collectors impregnated with special polymer sulphur binders, polymerized sulphur, which is applied as the industrial waste material. The city sewer collectors are settled with a colony of soil bacteria which have corrosive effects on its structure. Chemoautotrophic nitrifying bacteria utilize the residues of halites (carbamide) which migrate in the city sewer collectors, due to the damaged dampproofing of the roadway and produce nitrogen salts. Chemoorganotrophic bacteria utilize the traces of organic substrates and produce a number of organic acids (formic, acetic, propionic, citric, oxalic and other). The activity of microorganisms so enables the origination of primary and secondary salts which affect physical properties of concretes in city sewer collectors unfavourably.

Investigation of Pharmaceutical Residues in Hospital Effluents, in Ground- and Drinking Water from Bundeswehr Facilities, and their Removal During Drinking Water Purification (Arzneimittelrueckstaende in Trinkwasser(versorgungsanlagen) und Krankenhausabwaessern der Bundeswehr: Methodenentwicklung - Verkommen - Wasseraufbereitung)

DTIC Science & Technology

1999-11-01

Drinking water processing plant , Analysis, Calculation model, Field experiment 16. PRICE CODE 17. SECURITY CLASSIFICATION 18. SECURITY CLASSIFICATION...sewage effluents and from the sewer of the municipal sewage treatment plant in Berlin-Ruhleben. In the field trials, the MDWPUs that both apply reverse...waste water samples, along the municipal sewer system and In the influents and effluents of the receiving sewage treatment plants . To estimate the

Real-time control of sewer systems using turbidity measurements.

PubMed

Lacour, C; Schütze, M

2011-01-01

Real-time control (RTC) of urban drainage systems has been proven useful as a means to reduce pollution by combined sewer overflow discharges. So far, RTC has been investigated mainly with a sole focus on water quantity aspects. However, as measurement techniques for pollution of wastewater are advancing, pollution-based RTC might be of increasing interest. For example, turbidity data sets from an extensive measurement programme in two Paris catchments allow a detailed investigation of the benefits of using pollution-based data for RTC. This paper exemplifies this, comparing pollution-based RTC with flow-based RTC. Results suggest that pollution-based RTC indeed has some potential, particularly when measurements of water-quality characteristics are readily available.

MANAGEMENT AND CONTROL OF COMBINED SEWER OVERFLOWS

EPA Science Inventory

The paper gives a basic overview of the U.S. government's involvements in developing countermeasures for the abatement of combined sewer overflow pollution. batement or prevention of pollution stormwater runoff and combined sewer overflows is one of the most challenging areas in ...

Utility Bill Insert for Wastewater Services

EPA Pesticide Factsheets

Intended for use by wastewater and water supply utilities, one side of the utility bill insert has information for customers that discharge to sanitary sewer systems; the other side is for customers with septic systems.

URBAN WET-WEATHER FLOW MANAGEMENT: RESEARCH DIRECTIONS

EPA Science Inventory

There are three types of urban wet-weather flow (WWF) discharges: 1) combined-sewer overflow (CSO), which is a mixture of storm drainage and municipal-industrial wastewater discharged from combined sewers or dry-weather flow discharged from combined sewers due to clogged intercep...

Dynamics of rain-induced pollutographs of solubles in sewers.

PubMed

Rutsch, M; Müller, I; Krebs, P

2005-01-01

When looking at acute receiving water impacts due to combined sewer overflows the characteristics of the background diurnal sewage flux variation may influence the peak loads from combined sewer overflows (CSO) and wastewater treatment plant (WWTP) effluent significantly. In this paper, effects on the dynamic compounds transported in the sewer, on CSO discharges and WWTP loading are evaluated by means of hydrodynamic simulations. The simulations are based on different scenarios for diurnal dry-weather flow variations induced by different infiltration rates.

Remaining Sites Verification Package for the 1607-B2 Septic System and 100-B-14:2 Sanitary Sewer System, Waste Site Reclassification Form 2004-006

DOE Office of Scientific and Technical Information (OSTI.GOV)

L. M. Dittmer

The 100-B-14:2 subsite encompasses the former sanitary sewer feeder lines associated with the 1607-B2 and 1607-B7 septic systems. Feeder lines associated with the 185/190-B building have also been identified as the 100-B-14:8 subsite, and feeder lines associated with the 1607-B7 septic system have also been identified as the 100-B-14:9 subsite. These two subsites have been administratively cancelled to resolve the redundancy. The results of verification sampling show that residual contaminant concentrations do not preclude any future uses and allow for unrestricted use of shallow zone soils. The results also demonstrate that residual contaminant concentrations are protective of groundwater and themore » Columbia River.« less

Model evaluation of potential impacts of on-site wastewater systems on phosphorus in Turkey creek watershed.

PubMed

Geza, Mengistu; McCray, John E; Murray, Kyle E

2010-01-01

Nutrient loading to surface water systems has traditionally been associated with agricultural sources. Sources such as on-site wastewater systems (OWS) may be of concern especially in rural, nonagricultural watersheds. The impact of various point and nonpoint sources including OWS in Turkey Creek Watershed was evaluated using the Watershed Analysis Risk Management Framework, which was calibrated using 10 yr of observed stream flow and total P concentrations. Doubling the population in the watershed or OWS septic tank effluent P concentration increased mean stream total P concentration by a factor of 1.05. Converting all the OWS to a conventional sewer system with a removal efficiency of 93% at the wastewater treatment plant increased the mean total P concentration at the watershed outlet by a factor of 1.26. Reducing the soil adsorption capacity by 50% increased the mean stream total P concentration by a factor of 3.2. Doubling the initial P concentration increased the mean stream total P concentration by a factor of 1.96. Stream flow and sediment transport also substantially affected stream P concentration. The results suggest that OWS contribution to stream P in this watershed is minimal compared with other factors within the simulated time frame of 10 yr.

Economic and environmental assessment of office building rainwater harvesting systems in various U.S. cities.

PubMed

Wang, Ranran; Zimmerman, Julie B

2015-02-03

Rainwater harvesting (RWH) systems implemented in office buildings under heterogeneous urban settings in the United States, including combined and separated storm sewer systems, will result in varying environmental and economic costs and benefits across multiple water sectors. The potable water saving and stormwater abatement potentials were found to strongly correlate with the local annual precipitation totals and patterns, specifically the long-period antecedent dry weather period. Given the current water rates and stormwater fees in large U.S. cities, RWH systems implemented in office buildings may not be cost-effective compared to the municipal supplies over their lifetime, except in Seattle, which has the highest stormwater fees in the country ($77.50/1000 sf impervious surface/month). The minimum net life cycle costs range from -$1.60 (Seattle) to $11.9 (Phoenix) per m(3) of rainwater yield, resulting in a potential economic gain of over $520 (Seattle) to a net loss of $800 (Phoenix) per building annually. By preventing the rooftop runoff from entering the wastewater treatment plant, between 3 and 9 kg N eq per year could be reduced in combined sewer systems depending on local conditions. This N reduction comes at the expense 0.7-4.6 kg CO2 eq per m(3) rainwater yield. In separate sewer systems, eutrophication reduction benefits result from reducing N loading associated with stormwater runoff. The overall sustainability of implementing RWH depends on the site-specific functional, economic, and environmental benefits, impacts, and trade-offs.

Simulation of floods caused by overloaded sewer systems: extensions of shallow-water equations

NASA Astrophysics Data System (ADS)

Hilden, Michael

2005-03-01

The outflow of water from a manhole onto a street is a typical flow problem within the simulation of floods in urban areas that are caused by overloaded sewer systems in the event of heavy rains. The reliable assessment of the flood risk for the connected houses requires accurate simulations of the water flow processes in the sewer system and in the street.The Navier-Stokes equations (NSEs) describe the free surface flow of the fluid water accurately, but since their numerical solution requires high CPU times and much memory, their application is not practical. However, their solutions for selected flow problems are applied as reference states to assess the results of other model approaches.The classical shallow-water equations (SWEs) require only fractions (factor 1/100) of the NSEs' computational effort. They assume hydrostatic pressure distribution, depth-averaged horizontal velocities and neglect vertical velocities. These shallow-water assumptions are not fulfilled for the outflow of water from a manhole onto the street. Accordingly, calculations show differences between NSEs and SWEs solutions.The SWEs are extended in order to assess the flood risks in urban areas reliably within applicable computational efforts. Separating vortex regions from the main flow and approximating vertical velocities to involve their contributions into a pressure correction yield suitable results.

Quantifying radar-rainfall uncertainties in urban drainage flow modelling

NASA Astrophysics Data System (ADS)

Rico-Ramirez, M. A.; Liguori, S.; Schellart, A. N. A.

2015-09-01

This work presents the results of the implementation of a probabilistic system to model the uncertainty associated to radar rainfall (RR) estimates and the way this uncertainty propagates through the sewer system of an urban area located in the North of England. The spatial and temporal correlations of the RR errors as well as the error covariance matrix were computed to build a RR error model able to generate RR ensembles that reproduce the uncertainty associated with the measured rainfall. The results showed that the RR ensembles provide important information about the uncertainty in the rainfall measurement that can be propagated in the urban sewer system. The results showed that the measured flow peaks and flow volumes are often bounded within the uncertainty area produced by the RR ensembles. In 55% of the simulated events, the uncertainties in RR measurements can explain the uncertainties observed in the simulated flow volumes. However, there are also some events where the RR uncertainty cannot explain the whole uncertainty observed in the simulated flow volumes indicating that there are additional sources of uncertainty that must be considered such as the uncertainty in the urban drainage model structure, the uncertainty in the urban drainage model calibrated parameters, and the uncertainty in the measured sewer flows.

Spatial variability of polycyclic aromatic hydrocarbon load of urban wet weather pollution in combined sewers.

PubMed

Gasperi, J; Moilleron, R; Chebbo, G

2006-01-01

In Paris, the OPUR research programme created an experimental on-site observatory of urban pollutant loads in combined sewer systems in order to characterise the dry and wet weather flows at different spatial scales. This article presents the first results on the spatial variability of the polycyclic aromatic hydrocarbon (PAH) load during wet weather flow (WWF). At the scale of a rain event, investigations revealed that (i) PAH concentrations were relatively homogenous whatever the spatial scale and were greater than those of the dry weather flow (DWF), (ii) PAH distributions between dissolved and particulate phases were constant, and (iii) PAH fingerprints exhibited a similar pattern for all catchments. Moreover, an evaluation of the contribution of DWF, runoff and erosion of sewer deposits to WWF load was established. According to the hypothesis on the runoff concentration, the contributions were evaluated at 14, 8 and 78%, respectively, at the scale of the Marais catchment. For all the catchments, the runoff contribution was found quite constant and evaluated at approximately 10%. The DWF contribution seems to increase with the catchment area, contrary to the sewer erosion contribution, which seems to decrease. However, this latter still remains an important source of pollution. These first trends should be confirmed and completed by more investigations of rain events.

Dissolved oxygen in gravity sewers--measurement and simulation.

PubMed

Gudjonsson, G; Vollertsen, J; Hvitved-Jacobsen, T

2002-01-01

Dissolved oxygen (DO) concentrations were during 2 months continuously measured in an intercepting sewer. Measurements were made upstream and downstream in a 3.6 km gravity sewer. DO showed significant diurnal variations mainly caused by changes in the organic matter composition of the wastewater. At low temperatures the gravity sewer was strictly aerobic. However, towards the end of the measuring campaign, DO concentrations decreased as temperature increased and the sewer became anaerobic part of the day. A conceptual model that takes into account bulk water and biofilm DO uptake as well as reaeration was used to simulate the DO measured. Using measurements from the upstream station as input, the model was calibrated to yield good validation results of the DO at the downstream station.

Hydrogen sulphide removal from corroding concrete: comparison between surface removal rates and biomass activity.

PubMed

Jensen, H S; Nielsen, A H; Lens, P N L; Hvitved-Jacobsen, T; Vollertsen, J

2009-11-01

Corrosion of concrete sewer pipes caused by hydrogen sulphide is a problem in many sewer networks. The mechanisms of production and fate of hydrogen sulphide in the sewer biofilms and wastewater as well as its release to the sewer atmosphere are largely understood. In contrast, the mechanisms of the uptake of hydrogen sulphide on the concrete surfaces and subsequent concrete corrosion are basically unknown. To shed light on these mechanisms, the uptake of hydrogen sulphide from a sewer gas phase was compared to the biological hydrogen sulphide removal potential of the concrete corrosion products. The results showed that both microbial degradation at and sorption to the concrete surfaces were important for the uptake of hydrogen sulphide on the concrete surfaces.

Hydrogen sulfide emission in sewer networks: a two-phase modeling approach to the sulfur cycle.

PubMed

Yongsiri, C; Vollertsen, J; Hvitved-Jacobsen, T

2004-01-01

Wherever transport of anaerobic wastewater occurs, potential problems associated with hydrogen sulfide in relation to odor nuisance, health risk and corrosion exist. Improved understanding of prediction of hydrogen sulfide emission into the sewer atmosphere is needed for better evaluation of such problems in sewer networks. A two-phase model for emission of hydrogen sulfide along stretches of gravity sewers is presented to estimate the occurrence of both sulfide in the water phase and hydrogen sulfide in the sewer atmosphere. The model takes into account air-water mass transfer of hydrogen sulfide and interactions with other processes in the sulfur cycle. Various emission scenarios are simulated to illustrate the release characteristics of hydrogen sulfide.

Focused Field Investigations for Sewer Condition Assessment with EPA SSOAP Toolbox

EPA Science Inventory

The Nation’s sanitary sewer infrastructure is aging, and is currently one of the top national water program priorities. The U.S. Environmental Protection Agency (EPA) developed the Sanitary Sewer Overflow Analysis and Planning (SSOAP) Toolbox to assist communities in developing ...

Focused Field Investigations for Sewer Condition Assessment with EPA SSOAP Toolbox - slides

EPA Science Inventory

The Nation’s sanitary sewer infrastructure is aging, and is currently one of the top national water program priorities. The U.S. Environmental Protection Agency (EPA) developed the Sanitary Sewer Overflow Analysis and Planning (SSOAP) Toolbox to assist communities in developing S...

Remanence of lead pollution in an urban river system: a multi-scale temporal and spatial study in the Seine River basin, France.

PubMed

Ayrault, S; Le Pape, P; Evrard, O; Priadi, C R; Quantin, C; Bonté, P; Roy-Barman, M

2014-03-01

Total lead (Pb) concentration and Pb isotopic ratio ((206)Pb/(20)7Pb) were determined in 140 samples from the Seine River basin (France), covering a period of time from 1945 to 2011 and including bed sediments (bulk and size fractionated samples), suspended particulate matter (SPM), sediment cores, and combined sewer overflow (CSO) particulate matter to constrain the spatial and temporal variability of the lead sources at the scale of the contaminated Seine River basin. A focus on the Orge River subcatchment, which exhibits a contrasted land-use pattern, allows documenting the relation between hydrodynamics, urbanization, and contamination sources. The study reveals that the Pb contamination due to leaded gasoline that peaked in the 1980s has a very limited impact in the river nowadays. In the upstream Seine River, the isotopic ratio analysis suggests a pervasive contamination which origin (coal combustion and/or gasoline lead) should be clarified. The current SPM contamination trend follows the urbanization/industrialization spatial trend. Downstream of Paris, the lead from historical use originating from the Rio Tinto mine, Spain ((206)Pb/(207)Pb=1.1634 ± 0.0001) is the major Pb source. The analysis of the bed sediments (bulk and grain size fractionated) highlights the diversity of the anthropogenic lead sources in relation with the diversity of the human activities that occurred in this basin over the years. The "urban" source, defined by waste waters including the CSO samples ((206)Pb/(207)Pb=1.157 ± 0.003), results of a thorough mixing of leaded gasoline with "historical" lead over the years. Finally, a contamination mixing scheme related to hydrodynamics is proposed.

Wastewater Collection.

ERIC Educational Resources Information Center

Chatterjee, Samar; And Others

1978-01-01

Presents a literature review of wastewater collection systems and components. This review covers: (1) planning, (2) construction; (3) sewer system evaluation; (4) maintenance; (5) rehabilitation; (6) overview prevention; and (7) wastewater pumping. A list of 111 references is also presented. (HM)

Identification of controlling factors for the initiation of corrosion of fresh concrete sewers.

PubMed

Jiang, Guangming; Sun, Xiaoyan; Keller, Jurg; Bond, Philip L

2015-09-01

The development of concrete corrosion in new sewer pipes undergoes an initiation process before reaching an active corrosion stage. This initiation period is assumed to last several months to years but the key factors affecting the process, and its duration, are not well understood. This study is therefore focused on this initial stage of the corrosion process and the effect of key environmental factors. Such knowledge is important for the effective management of corrosion in new sewers, as every year of life extension of such systems has a very high financial benefit. This long-term (4.5 year) study has been conducted in purpose-built corrosion chambers that closely simulated the sewer environment, but with control of three key environmental factors being hydrogen sulfide (H2S) gas phase concentration, relative humidity and air temperature. Fresh concrete coupons, cut from an industry-standard sewer pipe, were exposed to the corrosive conditions in the chambers, both in the gas phase and partially submerged in wastewater. A total of 36 exposure conditions were investigated to determine the controlling factors by regular retrieval of concrete coupons for detailed analysis of surface pH, sulfur compounds (elemental sulfur and sulfate) and concrete mass loss. Corrosion initiation times were thus determined for different exposure conditions. It was found that the corrosion initiation time of both gas-phase and partially-submerged coupons was positively correlated with the gas phase H2S concentration, but only at levels of 10 ppm or below, indicating that sulfide oxidation rate rather than the H2S concentration was the limiting factor during the initiation stage. Relative humidity also played a role for the corrosion initiation of the gas-phase coupons. However, the partially-submerged coupons were not affected by humidity as these coupons were in direct contact with the sewage and hence did have sufficient moisture to enable the microbial processes to proceed. The corrosion initiation time was also shortened by higher gas temperature due to its positive impact on reaction kinetics. These findings provide real opportunities for pro-active sewer asset management with the aim to delay the on-set of the corrosion processes, and hence extend the service life of sewers, through improved prediction and optimization capacity. Copyright © 2015 Elsevier Ltd. All rights reserved.

VERIFICATION OF URBAN RUNOFF MODELS

EPA Science Inventory

Wet Weather Flow Models are used throughout the United States for evaluation of the sanitary, storm and combined sewer systems. Models are used for planning new systems or upgrading of existing systems to accommodate growth or to control undersirable overflows and associated wat...

Flood Grouting for Infiltration Reduction on Private Side Sewers (WERF Report INFR5R11)

EPA Science Inventory

The sewers in Seattle’s Broadview neighborhood, built in the 1950s, experience significant inflow and infiltration. Intense wet weather events have resulted in sewer overflows into private residences and the environment and previous work indicates that the majority of this excess...

Focused Field Investigations for Sewer Condition Assessment with EPA SSOAP Toolbox - abstract

EPA Science Inventory

The Nation’s sanitary sewer infrastructure is aging, and it is currently one of the top national water program priorities, and is one of the top priorities of the U.S. Conference of Mayors. The U.S. Environmental Protection Agency developed the Sanitary Sewer Overflow Analysis a...

40 CFR 35.2130 - Sewer use ordinance.

Code of Federal Regulations, 2012 CFR

2012-07-01

... integrity of the treatment works; cause violation of effluent or water quality limitations; or preclude the... STATE AND LOCAL ASSISTANCE Grants for Construction of Treatment Works § 35.2130 Sewer use ordinance. The... any new connections from inflow sources into the treatment works and require that new sewers and...

40 CFR 35.2130 - Sewer use ordinance.

Code of Federal Regulations, 2014 CFR

2014-07-01

... integrity of the treatment works; cause violation of effluent or water quality limitations; or preclude the... STATE AND LOCAL ASSISTANCE Grants for Construction of Treatment Works § 35.2130 Sewer use ordinance. The... any new connections from inflow sources into the treatment works and require that new sewers and...

Focused Field Investigations for Sewer Condition Assessment with EPA SSOAP Toolbox

EPA Science Inventory

The Nation’s sanitary sewer infrastructure is aging, and it is currently one of the top national water program priorities, and is one of the top priorities of the U.S. Conference of Mayors. The U.S. Environmental Protection Agency (EPA) developed the Sanitary Sewer Overflow Anal...

The comparison of greenhouse gas emissions in sewage treatment plants with different treatment processes.

PubMed

Masuda, Shuhei; Sano, Itsumi; Hojo, Toshimasa; Li, Yu-You; Nishimura, Osamu

2018-02-01

Greenhouse gas emissions from different sewage treatment plants: oxidation ditch process, double-circulated anoxic-oxic process and anoxic-oxic process were evaluated based on the survey. The methane and nitrous oxide characteristics were discussed based on the gaseous and dissolved gas profiles. As a result, it was found that methane was produced in the sewer pipes and the primary sedimentation tank. Additionally, a ventilation system would promote the gasification of dissolved methane in the first treatment units. Nitrous oxide was produced and emitted in oxic tanks with nitrite accumulation inside the sewage treatment plant. A certain amount of nitrous oxide was also discharged as dissolved gas through the effluent water. If the amount of dissolved nitrous oxide discharge is not included, 7-14% of total nitrous oxide emission would be overlooked. Based on the greenhouse gas calculation, electrical consumption and the N 2 O emission from incineration process were major sources in all the plants. For greenhouse gas reduction, oxidation ditch process has an advantage over the other advanced systems due to lower energy consumption, sludge production, and nitrogen removal without gas stripping. Copyright © 2017 Elsevier Ltd. All rights reserved.

Comparison of Storage Capacity and Sedimentation Trends of Lago Guayabal, Puerto Rico-December 2001 and October 2006

USGS Publications Warehouse

Soler-López, Luis R.

2008-01-01

Lago Guayabal dam is located on the Rio Jacaguas in the municipality of Villalba in southern Puerto Rico, about 4 kilometers north of the town of Juana Diaz and about 5 kilometers south of Villalba (fig. 1). The dam is owned and operated by the Puerto Rico Electric Power Authority (PREPA) and was constructed in 1913 for the irrigation of croplands in the southern coastal plains of Puerto Rico. The reservoir impounds the waters of the Rio Jacaguas and those of the Rio Toa Vaca, when the Toa Vaca dam overflows or releases water. The reservoir has a drainage area of 53.8 square kilometers. The dam is a concrete gravity structure with a normal pool (at top of flashboards) elevation of 103.94 meters above mean sea level (Puerto Rico Electric Power Authority, 1988). During October 2006, the U.S. Geological Survey (USGS), Caribbean Water Science Center, in cooperation with the Puerto Rico Aqueduct and Sewer Authority (PRASA) conducted a bathymetric survey of Lago Guayabal to update the reservoir storage capacity and actualize the reservoir sedimentation rate by comparing the 2006 data with the previous 2001 bathymetric survey results. The purpose of this report is to describe and document the USGS sedimentation survey conducted at Lago Guayabal during October 2006, including the methods used to update the reservoir storage capacity, sedimentation rates, and areas of substantial sediment accumulation since December 2001. The Lago Guayabal sedimentation history up to 2001 was published by the USGS in 2003 (Soler-Lopez, 2003); therefore, this report focuses on the comparison between the 2001 and current bathymetric surveys of Lago Guayabal.

A catchment-scale groundwater model including sewer pipe leakage in an urban system

NASA Astrophysics Data System (ADS)

Peche, Aaron; Fuchs, Lothar; Spönemann, Peter; Graf, Thomas; Neuweiler, Insa

2016-04-01

Keywords: pipe leakage, urban hydrogeology, catchment scale, OpenGeoSys, HYSTEM-EXTRAN Wastewater leakage from subsurface sewer pipe defects leads to contamination of the surrounding soil and groundwater (Ellis, 2002; Wolf et al., 2004). Leakage rates at pipe defects have to be known in order to quantify contaminant input. Due to inaccessibility of subsurface pipe defects, direct (in-situ) measurements of leakage rates are tedious and associated with a high degree of uncertainty (Wolf, 2006). Proposed catchment-scale models simplify leakage rates by neglecting unsaturated zone flow or by reducing spatial dimensions (Karpf & Krebs, 2013, Boukhemacha et al., 2015). In the present study, we present a physically based 3-dimensional numerical model incorporating flow in the pipe network, in the saturated zone and in the unsaturated zone to quantify leakage rates on the catchment scale. The model consists of the pipe network flow model HYSTEM-EXTAN (itwh, 2002), which is coupled to the subsurface flow model OpenGeoSys (Kolditz et al., 2012). We also present the newly developed coupling scheme between the two flow models. Leakage functions specific to a pipe defect are derived from simulations of pipe leakage using spatially refined grids around pipe defects. In order to minimize computational effort, these leakage functions are built into the presented numerical model using unrefined grids around pipe defects. The resulting coupled model is capable of efficiently simulating spatially distributed pipe leakage coupled with subsurficial water flow in a 3-dimensional environment. References: Boukhemacha, M. A., Gogu, C. R., Serpescu, I., Gaitanaru, D., & Bica, I. (2015). A hydrogeological conceptual approach to study urban groundwater flow in Bucharest city, Romania. Hydrogeology Journal, 23(3), 437-450. doi:10.1007/s10040-014-1220-3. Ellis, J. B., & Revitt, D. M. (2002). Sewer losses and interactions with groundwater quality. Water Science and Technology, 45(3), 195-202. itwh (2002). Modellbeschreibung, Institut für technisch-wissenschaftliche Hydrologie GmbH, Hannover. Karpf, C. & Krebs, P. (2013). Modelling of groundwater infiltration into sewer systems. Urban Water Journal, 10:4, 221-229, DOI: 10.1080/1573062X.2012.724077. Kolditz, O., Bauer, S. et al. (2012). OpenGeoSys: an open source initiative for numerical simulation of thermo-hydro-mechanical/chemical (THM/C) processes in porous media. Env. Earth Sci. 67(2):589-599. Wolf, L., Held, I., Eiswirth, M., & Hötzl, H. (2004). Impact of leaky sewers on groundwater quality. Acta Hydrochimica et Hydrobiologica, 32(4-5), 361-373. doi:10.1002/aheh.200400538. Wolf, L. (2006). Influence of leaky sewer systems on groundwater resources beneath the city of Rastatt, Germany. Dissertation, University of Karlsruhe.

Infiltration and hydraulic connections from the Niagara River to a fractured-dolomite aquifer in Niagara Falls, New York

USGS Publications Warehouse

Yager, R.M.; Kappel, W.M.

1998-01-01

The spatial distribution of hydrogen and oxygen stable-isotope values in groundwater can be used to distinguish different sources of recharge and to trace groundwater flow directions from recharge boundaries. This method can be particularly useful in fractured-rock settings where multiple lines of evidence are required to delineate preferential flow paths that result from heterogeneity within fracture zones. Flow paths delineated with stable isotopes can be combined with hydraulic data to form a more complete picture of the groundwater flow system. In this study values of ??D and ??18O were used to delineate paths of river-water infiltration into the Lockport Group, a fractured dolomite aquifer, and to compute the percentage of fiver water in groundwater samples from shallow bedrock wells. Flow paths were correlated with areas of high hydraulic diffusivity in the shallow bedrock that were delineated from water-level fluctuations induced by diurnal stage fluctuations in man-made hydraulic structures. Flow paths delineated with the stable-isotope and hydraulic data suggest that fiver infiltration reaches an unlined storm sewer in the bedrock through a drainage system that surrounds aqueducts carrying river water to hydroelectric power plants. This finding is significant because the storm sewer is the discharge point for contaminated groundwater from several chemical waste-disposal sites and the cost of treating the storm sewer's discharge could be reduced if the volume of infiltration from the river were decreased.The spatial distribution of hydrogen and oxygen stable-isotope values in groundwater can be used to distinguish different sources of recharge and to trace groundwater flow directions from recharge boundaries. This method can be particularly useful in fractured-rock settings where multiple lines of evidence are required to delineate preferential flow paths that result from heterogeneity within fracture zones. Flow paths delineated with stable isotopes can be combined with hydraulic data to form a more complete picture of the groundwater flow system. In this study values of ??D and ??18O were used to delineate paths of river-water infiltration into the Lockport Group, a fractured dolomite aquifer, and to compute the percentage of river water in groundwater samples from shallow bedrock wells. Flow paths were correlated with areas of high hydraulic diffusivity in the shallow bedrock that were delineated from water-level fluctuations induced by diurnal stage fluctuations in man-made hydraulic structures. Flow paths delineated with the stable-isotope and hydraulic data suggest that river infiltration reaches an unlined storm sewer in the bedrock through a drainage system that surrounds aqueducts carrying river water to hydroelectric power plants. This finding is significant because the storm sewer is the discharge point for contaminated groundwater from several chemical waste-disposal sites and the cost of treating the storm sewer's discharge could be reduced if the volume of infiltration from the river were decreased.

Estimation of combined sewer overflow discharge: a software sensor approach based on local water level measurements.

PubMed

Ahm, Malte; Thorndahl, Søren; Nielsen, Jesper E; Rasmussen, Michael R

2016-12-01

Combined sewer overflow (CSO) structures are constructed to effectively discharge excess water during heavy rainfall, to protect the urban drainage system from hydraulic overload. Consequently, most CSO structures are not constructed according to basic hydraulic principles for ideal measurement weirs. It can, therefore, be a challenge to quantify the discharges from CSOs. Quantification of CSO discharges are important in relation to the increased environmental awareness of the receiving water bodies. Furthermore, CSO discharge quantification is essential for closing the rainfall-runoff mass-balance in combined sewer catchments. A closed mass-balance is an advantage for calibration of all urban drainage models based on mass-balance principles. This study presents three different software sensor concepts based on local water level sensors, which can be used to estimate CSO discharge volumes from hydraulic complex CSO structures. The three concepts were tested and verified under real practical conditions. All three concepts were accurate when compared to electromagnetic flow measurements.

Sedimentation Survey of Lago de Cidra, Puerto Rico, August 2007

USGS Publications Warehouse

Soler-López, Luis R.

2010-01-01

Lago de Cidra is a reservoir located on the confluence of Rio de Bayamon, Rio Sabana, and Quebrada Prieta, in the municipality of Cidra in east-central Puerto Rico, about 3.0 kilometers northeast of the town of Cidra. The dam is owned and operated by the Puerto Rico Aqueduct and Sewer Authority (PRASA), and was constructed in 1946 as a 6.54-million-cubic-meter supplemental water supply for the San Juan metropolitan area. The reservoir impounds the waters of Rio de Bayamon, Rio Sabana and Quebrada Prieta. The reservoir has a drainage area of 21.4 square kilometers. The dam is a concrete gravity and earthfill structure with a length of approximately 165 meters and a structural height of 24 meters. The spillway portion of the dam is an ungated ogee crest about 40 meters long with a crest elevation of 403.00 meters above mean sea level. Additional information and operational procedures are listed in Soler-Lopez (1999). During August 14-15, 2007, the U.S. Geological Survey (USGS), Caribbean Water Science Center (CWSC), in cooperation with the PRASA, conducted a bathymetric survey of Lago de Cidra to update the reservoir storage capacity and actualize the reservoir sedimentation rate by comparing the 2007 data with the previous 1997 bathymetric survey data. The purpose of this report is to describe and document the USGS sedimentation survey conducted at Lago de Cidra during August 2007, including the methods used to update the reservoir storage capacity, sedimentation rates, and areas of substantial sediment accumulation since 1997.

DECISION SUPPORT TOOLS FOR MANAGING WASTEWATER COLLECTION SYSTEMS

EPA Science Inventory

Wastewater collection systems are an extensive part of the nation's infrastructure. In the US approximately 150M people are served by about 19,000 municipal wastewater collection systems representing about 500,000 miles of sewer pipe (not including privately owned service lateria...

Monitoring and analysis of combined sewer overflows, Riverside and Evanston, Illinois, 1997-99

USGS Publications Warehouse

Waite, Andrew M.; Hornewer, Nancy J.; Johnson, Gary P.

2002-01-01

The U.S. Geological Survey, in cooperation with the U.S. Army Corps of Engineers, collected and analyzed flow data in combined sewer systems in Riverside and Evanston, northeastern Illinois, from March 1997 to December 1999. Continuous 2- and 5-minute stage and velocity data were collected during surcharged and nonsurcharged conditions at 12 locations. Mass balances were calculated to determine the volume of water flowing through the tide-gate openings to the Des Plaines River and the North Shore Channel and to determine the volume of water flowing past the sluice gate to the deep tunnel. The sewer systems consist of circular pipes ranging in diameter from 0.83 feet to 10.0 feet, elliptical siphon pipes, ledges, and tide and sluice gates. Pipes were constructed of either brick and mortar or concrete, and ranged from having smooth surfaces to rough, pitted and crumbling surfaces. One pipe was noticeably affected by water infiltration from saturated ground. During data analysis, many assumptions were necessary because of the complexity of the flow data and sewer-system configurations. These assumptions included estimating the volume of water entering an interceptor sewer at the ''Gage Street pipe'' at Riverside, the effect of infiltration on the ''brick pipe'' at Riverside, and the minimum velocity required for the meter to make an accurate velocity determination. Other factors affecting the analysis of flow data included possible non-instrumented sources of inflow, and backwater conditions in some pipes, which could have caused error in the data analysis. Variations of these assumptions potentially could cause appreciable changes to the final massbalance calculations. Mass-balance analysis at Riverside indicated a total inflow volume into chamber 3 of approximately 721,000 cubic feet (ft3) during April 22-26, 1999. Outflow volume to the Des Plaines River at Riverside through the tide gate was approximately 132,000 ft3; outflow volume to the deep tunnel through the sluice gate was approximately 267,000 ft3. The mass-balance analysis at Evanston indicated a total inflow volume into chamber 3 of approximately 5,970,000 ft3 during April 21-26, 1999. The outflow volume to the North Shore Channel through the tide gates at Evanston was approximately 2,920,000 ft3; outflow volume to the deep tunnel through the sluice gates was approximately 3,050,000 ft3.

Cost Comparison of Conventional Gray Combined Sewer Overflow Control Infrastructure versus a Green/Gray Combination

EPA Science Inventory

This paper outlines a life-cycle cost analysis comparing a green (rain gardens) and gray (tunnels) infrastructure combination to a gray-only option to control combined sewer overflow in the Turkey Creek Combined Sewer Overflow Basin, in Kansas City, MO. The plan area of this Bas...

The Distribution and Movement of American Cockroaches in Urban Niches of New Orleans.

PubMed

Carlson, John C; Rabito, Felicia A; Werthmann, Derek; Fox, Mark

2017-10-01

American cockroaches are an important source of household allergens in tropical and semitropical climates. To determine which outdoor niches produce American cockroaches, traps were placed at 40 homes in New Orleans to collect nymphs. Nymphs were collected from the sewers, yards, and within the homes themselves. To compare sewers and yards as sources of cockroaches entering homes, adult cockroaches were collected, marked, and released into yards and sewers. No sewer-released cockroaches were collected in homes. Cockroaches released into yards were collected in the homes, suggesting that yards, rather than sewers, are a more important source niche. A field trial applying boric acid granules to the yard was performed in an effort to reduce entry of cockroaches. There was a significant reduction in the cockroach antigen collected in intervention homes compared with controls.

Using Agent-Based Modeling to Enhance System-Level Real-time Control of Urban Stormwater Systems

NASA Astrophysics Data System (ADS)

Rimer, S.; Mullapudi, A. M.; Kerkez, B.

2017-12-01

The ability to reduce combined-sewer overflow (CSO) events is an issue that challenges over 800 U.S. municipalities. When the volume of a combined sewer system or wastewater treatment plant is exceeded, untreated wastewater then overflows (a CSO event) into nearby streams, rivers, or other water bodies causing localized urban flooding and pollution. The likelihood and impact of CSO events has only exacerbated due to urbanization, population growth, climate change, aging infrastructure, and system complexity. Thus, there is an urgent need for urban areas to manage CSO events. Traditionally, mitigating CSO events has been carried out via time-intensive and expensive structural interventions such as retention basins or sewer separation, which are able to reduce CSO events, but are costly, arduous, and only provide a fixed solution to a dynamic problem. Real-time control (RTC) of urban drainage systems using sensor and actuator networks has served as an inexpensive and versatile alternative to traditional CSO intervention. In particular, retrofitting individual stormwater elements for sensing and automated active distributed control has been shown to significantly reduce the volume of discharge during CSO events, with some RTC models demonstrating a reduction upwards of 90% when compared to traditional passive systems. As more stormwater elements become retrofitted for RTC, system-level RTC across complete watersheds is an attainable possibility. However, when considering the diverse set of control needs of each of these individual stormwater elements, such system-level RTC becomes a far more complex problem. To address such diverse control needs, agent-based modeling is employed such that each individual stormwater element is treated as an autonomous agent with a diverse decision making capabilities. We present preliminary results and limitations of utilizing the agent-based modeling computational framework for the system-level control of diverse, interacting stormwater elements.

Water-quality and biologic data for the Blue River basin, Kansas City metropolitan area, Missouri and Kansas, October 2000 to October 2004

USGS Publications Warehouse

Wilkison, Donald H.; Armstrong, Daniel J.; Brown, Rebecca E.; Poulton, Barry C.; Cahill, Jeffrey D.; Zaugg, Steven D.

2005-01-01

This report presents water-quality and biologic data collected in the Blue River Basin, metropolitan Kansas City, Missouri and Kansas, from October 2000 to October 2004. Data were collected in cooperation with the city of Kansas City, Missouri, Water Services Department as part of an ongoing study designed to characterize long-term water-quality trends in the basin and to provide data to support a strategy for combined sewer overflow control. These data include values of physical properties, fecal indicator bacteria densities, suspended sediment, and concentrations of major ions, nutrients, trace elements, organic wastewater compounds, and pharmaceutical compounds in base-flow and stormflow stream samples and bottom sediments. Six surface-water sites in the basin were sampled 13 times during base-flow conditions and during a minimum of 7 storms. Benthic macroinvertebrate communities are described at 10 sites in the basin and 1 site outside the basin. Water-column and bottom-sediment data from impounded reaches of Brush Creek are provided. Continuous specific conductance, pH, water-quality temperature, turbidity, and dissolved oxygen data are provided for two streams-the Blue River and Brush Creek. Sampling, analytical, and quality assurance methods used in data collection during the study also are described in the report.

Characterization and risk assessment of seasonal and weather dynamics in organic pollutant mixtures from discharge of a separate sewer system.

PubMed

Beckers, Liza-Marie; Busch, Wibke; Krauss, Martin; Schulze, Tobias; Brack, Werner

2018-05-15

Sites of wastewater discharge are hotspots for pollution of freshwaters with organic micropollutants and are often associated with adverse effects to aquatic organisms. The assessment, monitoring and managment of these hotspots is challenged by variations in the pollutant mixture composition due to season, weather conditions and random spills. In this study, we unraveled temporal exposure patterns in organic micropollutant mixtures from wastewater discharge and analyzed respective acute and sublethal risks for aquatic organisms. Samples were taken from two components of a separate sewer system i) a wastewater treatment plant (WWTP) and ii) a rain sewer of a medium size town as well as from the receiving river in different seasons. Rain sewer samples were separately collected for rain and dry - weather conditions. We analyzed 149 compounds by liquid chromatography-tandem mass spectrometry (LC-MS/MS). By considering the pollution dynamics in the point sources, we reduced the complexity of pollutant mixtures by k-means clustering to a few emission groups representing temporal and weather-related pollution patterns. From these groups, we derived biological quality element (BQE) - specific risk patterns. In most cases, one main risk driving emission group and a few individual risk driving compounds were identified for each BQE. While acute risk for fish was quite low, algae were exposed to seasonally emitted herbicides (terbuthylazine, spiroxamine) and crustaceans to randomly spilled insecticides (diazinon, dimethoate). Sublethal risks for all BQE were strongly influenced by constantly emitted pollutants, above all, pharmaceuticals. Variability of risks in the river was mainly driven by water discharge of the river rather than by season or peak events. Overall, the studied WWTP represented the major pollution source with a specific emission of agricultural compounds. However, the investigated rain sewer showed to be a constant pollution source due to illicit connections and was an important entry route for high loads of insecticides and biocides due to spills or incorrect disposal. By considering these pollution and risk dynamics, monitoring strategies may be optimized with a special focus on times of low flow conditions in the river, rain events and seasonally emitted risk drivers. Copyright © 2018 Elsevier Ltd. All rights reserved.

Modelling total suspended solids, E. coli and carbamazepine, a tracer of wastewater contamination from combined sewer overflows

NASA Astrophysics Data System (ADS)

Pongmala, Khemngeun; Autixier, Laurène; Madoux-Humery, Anne-Sophie; Fuamba, Musandji; Galarneau, Martine; Sauvé, Sébastien; Prévost, Michèle; Dorner, Sarah

2015-12-01

Urban source water protection requires knowledge of sources of fecal contamination upstream of drinking water intakes. Combined and sanitary sewer overflows (CSOs and SSOs) are primary sources of microbiological contamination and wastewater micropollutants (WWMPs) in urban water supplies. To quantify the impact of sewer overflows, predictive simulation models are required and have not been widely applied for microbial contaminants such as fecal indicator bacteria and pathogens in urban drainage networks. The objective of this study was to apply a simulation model to estimate the dynamics of three contaminants in sewer overflows - total suspended solids, Escherichia coli (E. coli) and carbamazepine, a WWMP. A mixed combined and pseudo-sanitary drainage network in Québec, Canada was studied and modelled for a total of 7 events for which water quality data were available. Model results were significantly correlated with field water quality data. The model confirmed that the contributions of E. coli from runoff and sewer deposits were minor and their dominant source was from sewage. In contrast, the main sources of total suspended solids were stormwater runoff and sewer resuspension. Given that it is not present in stormwater, carbamazepine was found to be a useful stable tracer of sewage contributions to total contaminant loads and also provided an indication of the fraction of total suspended solids originating from sewer deposits because of its similar response to increasing flowrates.

Electrochemical oxidation of iron and alkalinity generation for efficient sulfide control in sewers.

PubMed

Lin, Hui-Wen; Kustermans, Caroline; Vaiopoulou, Eleni; Prévoteau, Antonin; Rabaey, Korneel; Yuan, Zhiguo; Pikaar, Ilje

2017-07-01

The addition of iron salts is one of the most commonly used dosing strategies for sulfide control in sewers. However, iron salts decrease the sewage pH which not only reduces the effectiveness of sulfide precipitation but also enhances the release of residual sulfide to the sewer atmosphere. Equally important, concentrated iron salt solutions are corrosive and their frequent transport, handling, and on-site storage often come with Occupational Health and Safety (OH&S) concerns. Here, we experimentally demonstrated a novel sulfide control approach using electrochemical systems with parallel placed iron electrodes. This enabled combining anodic dissolved iron species release with cathodic hydroxyl anion production, which alleviates all the aforementioned concerns. A long-term experiment was successfully carried out achieving an average sulfide removal efficiency of 95.4 ± 4.4% at low voltage input of 2.90 ± 0.54 V over the course of 8 weeks. This electrochemical method was demonstrated to successfully achieve efficient sulfide control. In addition, it increases the sewage pH, thereby overcoming the drawbacks associated with the pH decrease in the case of conventional iron salt dosing. Ferrous ions were produced at an overall coulombic efficiency (CE) of 98.2 ± 1.2%, whereas oxygen evolution and direct sulfide oxidation were not observed. Short-term experiments showed that increasing either inter-electrode gap or current density increased the cell voltage associated with the increase in the ohmic drop of the system. Overall, this study highlights the practical potential of in-situ generation of dissolved iron species and simultaneous hydroxyl anion generation for efficient sulfide control in sewers. Copyright © 2017 Elsevier Ltd. All rights reserved.

Modeling and identifying the sources of radiocesium contamination in separate sewerage systems.

PubMed

Pratama, Mochamad Adhiraga; Yoneda, Minoru; Yamashiki, Yosuke; Shimada, Yoko; Matsui, Yasuto

2018-05-01

The Fukushima Dai-ichi nuclear power plant accident released radiocesium in large amounts. The released radionuclides contaminated much of the surrounding environment, including sewers in urban areas of Fukushima prefecture. In this study we attempted to identify and quantify the sources of radiocesium contamination in separate sewerage systems and developed a compartment model based on the Radionuclide Migration in Urban Environments and Drainage Systems (MUD) model. Measurements of the time-dependent radiocesium concentration in sewer sludge combined with meteorological, demographic, and radiocesium dietary intake data indicated that rainfall-derived inflow and infiltration (RDII) and human excretion were the chief contributors of radiocesium contamination in a separate sewerage system. The quantities of contamination derived from RDII and human excretion were calculated and used in the modified MUD model to simulate radiocesium contamination in sewers in three urban areas in Fukushima prefecture: Fukushima, Koriyama, and Nihonmatsu Cities. The Nash efficiency coefficient (0.88-0.92) and determination coefficient (0.89-0.93) calculated in an evaluation of our compartment model indicated that the model produced satisfactory results. We also used the model to estimate the total volume of sludge with radiocesium concentrations in excess of the clearance level, based on the number of months elapsed after the accident. Estimations by our model suggested that wastewater treatment plants (WWTPs) in Fukushima, Koriyama, and Nihonmatsu generated about 1,750,000m 3 of radioactive sludge in total, a level in good agreement with the real data. Copyright © 2017 Elsevier B.V. All rights reserved.

20 CFR 654.406 - Excreta and liquid waste disposal.

Code of Federal Regulations, 2014 CFR

2014-04-01

... subsurface septic tank-seepage system or other type of liquid waste treatment and disposal system, privies or... RESPONSIBILITIES OF THE EMPLOYMENT SERVICE SYSTEM Housing for Agricultural Workers Housing Standards § 654.406... accumulate on the ground surface. (b) Where public sewer systems are available, all facilities for disposal...

20 CFR 654.406 - Excreta and liquid waste disposal.

Code of Federal Regulations, 2010 CFR

2010-04-01

... subsurface septic tank-seepage system or other type of liquid waste treatment and disposal system, privies or... RESPONSIBILITIES OF THE EMPLOYMENT SERVICE SYSTEM Housing for Agricultural Workers Housing Standards § 654.406... accumulate on the ground surface. (b) Where public sewer systems are available, all facilities for disposal...

20 CFR 654.406 - Excreta and liquid waste disposal.

Code of Federal Regulations, 2011 CFR

2011-04-01

... subsurface septic tank-seepage system or other type of liquid waste treatment and disposal system, privies or... RESPONSIBILITIES OF THE EMPLOYMENT SERVICE SYSTEM Housing for Agricultural Workers Housing Standards § 654.406... accumulate on the ground surface. (b) Where public sewer systems are available, all facilities for disposal...

20 CFR 654.406 - Excreta and liquid waste disposal.

Code of Federal Regulations, 2012 CFR

2012-04-01

... subsurface septic tank-seepage system or other type of liquid waste treatment and disposal system, privies or... RESPONSIBILITIES OF THE EMPLOYMENT SERVICE SYSTEM Housing for Agricultural Workers Housing Standards § 654.406... accumulate on the ground surface. (b) Where public sewer systems are available, all facilities for disposal...

20 CFR 654.406 - Excreta and liquid waste disposal.

Code of Federal Regulations, 2013 CFR

2013-04-01

... subsurface septic tank-seepage system or other type of liquid waste treatment and disposal system, privies or... RESPONSIBILITIES OF THE EMPLOYMENT SERVICE SYSTEM Housing for Agricultural Workers Housing Standards § 654.406... accumulate on the ground surface. (b) Where public sewer systems are available, all facilities for disposal...

Self-Replenishable Anti-Waxing Organogel Materials.

PubMed

Yao, Xi; Wu, Shuwang; Chen, Lie; Ju, Jie; Gu, Zhandong; Liu, Mingjie; Wang, Jianjun; Jiang, Lei

2015-07-27

Solid deposition, such as the formation of ice on outdoor facilities, the deposition of scale in water reservoirs, the sedimentation of fat, oil, and grease (FOG) in sewer systems, and the precipitation of wax in petroleum pipelines, cause a serious waste of resources and irreversible environmental pollution. Inspired by fish and pitcher plants, we present a self-replenishable organogel material which shows ultra-low adhesion to solidified paraffin wax and crude oil by absorption of low-molar-mass oil from its crude-oil environment. Adhesion of wax on the organogel surface was over 500 times lower than adhesion to conventional material surfaces and the wax was found to slide off under the force of gravity. This design concept of a gel with decreased adhesion to wax and oil can be extended to deal with other solid deposition problems. © 2015 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA. This is an open access article under the terms of the Creative Commons Attribution Non-Commercial License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited and is not used for commercial purposes.

Extreme Precipitation and Emergency Room Visits for Gastrointestinal Illness in Areas with and without Combined Sewer Systems: An Analysis of Massachusetts Data, 2003-2007.

PubMed

Jagai, Jyotsna S; Li, Quanlin; Wang, Shiliang; Messier, Kyle P; Wade, Timothy J; Hilborn, Elizabeth D

2015-09-01

Combined sewer overflows (CSOs) occur in combined sewer systems when sewage and stormwater runoff are released into water bodies, potentially contaminating water sources. CSOs are often caused by heavy precipitation and are expected to increase with increasing extreme precipitation associated with climate change. The aim of this study was to assess whether the association between heavy rainfall and rate of emergency room (ER) visits for gastrointestinal (GI) illness differed in the presence of CSOs. For the study period 2003-2007, time series of daily rate of ER visits for GI illness and meteorological data were organized for three exposure regions: a) CSOs impacting drinking water sources, b) CSOs impacting recreational waters, c) no CSOs. A distributed lag Poisson regression assessed cumulative effects for an 8-day lag period following heavy (≥ 90th and ≥ 95th percentile) and extreme (≥ 99th percentile) precipitation events, controlling for temperature and long-term time trends. The association between extreme rainfall and rate of ER visits for GI illness differed among regions. Only the region with drinking water exposed to CSOs demonstrated a significant increased cumulative risk for rate (CRR) of ER visits for GI for all ages in the 8-day period following extreme rainfall: CRR: 1.13 (95% CI: 1.00, 1.28) compared with no rainfall. The rate of ER visits for GI illness was associated with extreme precipitation in the area with CSO discharges to a drinking water source. Our findings suggest an increased risk for GI illness among consumers whose drinking water source may be impacted by CSOs after extreme precipitation. Jagai JS, Li Q, Wang S, Messier KP, Wade TJ, Hilborn ED. 2015. Extreme precipitation and emergency room visits for gastrointestinal illness in areas with and without combined sewer systems: an analysis of Massachusetts data, 2003-2007. Environ Health Perspect 123:873-879; http://dx.doi.org/10.1289/ehp.1408971.

Turbidity dynamics during spring storm events in an urban headwater river system: the Upper Tame, West Midlands, UK.

PubMed

Lawler, D M; Petts, G E; Foster, I D L; Harper, S

2006-05-01

Turbidity is an important water quality variable, through its relation to light suppression, BOD impact, sediment-associated contaminant transport, and suspended sediment effects on organisms and habitats. Yet few published field investigations of wet-weather turbidity dynamics, through several individual and sequenced rainstorms in extremely urbanised headwater basins, have emerged. This paper aims to address this gap through a turbidity analysis of multiple storm events in spring 2001 in an urban headwater basin (57 km2) of the River Tame, central England, the most urbanised basin for its size in the UK ( approximately 42%). Data were collected at 15-min frequency at automated monitoring stations for rainfall, streamflow and six water quality variables (turbidity, EC, temperature, DO, pH, ammonia). Disturbance experiments also allowed estimates of bed sediment storage to be obtained. Six important and unusual features of the storm event turbidity response were apparent: (1) sluggish early turbidity response, followed by a turbidity 'rush'; (2) quasi-coincident flow and turbidity peaks; (3) anti-clockwise hysteresis in the discharge-turbidity relationship on all but one event, resulting from Falling-LImb Turbidity Extensions (FLITEs); (4) increases in peak turbidity levels through storm sequences; (5) initial micro-pulses (IMP) in turbidity; and (6) secondary turbidity peaks (STP) or 'turbidity shoulders' (TS). These features provided very little evidence of a true 'first-flush' effect: instead, substantial suspended solids transport continued right through the flow recessions, and little storm-event sediment exhaustion was evident. A new, dimensionless, hysteresis index, HI(mid), is developed to quantify the magnitude and direction of hysteresis in a simple, clear, direct and intuitive manner. This allowed the degree of departure from the classic 'first-flush', clockwise hysteresis models to be assessed. Of the 15 turbidity events considered, 10 coincided with ammonia spikes of up to 6.25 mg l(-1) at Water Orton (the downstream station): this suggests that spills from combined sewer overflows (CSO) or waste water treatment works (WwTWs) are significant in the throughput of turbid waters here. Substantial ammonia peaks related most strongly to total storm rainfall receipt, of four rainfall variables considered, and significant ammonia peaks were generated even from low-magnitude storms (rainfall totals <4 mm), indicating that spills are a frequent occurrence. Local bed sediment stores appear to be limited, suggesting that other distal sediment sources, such as road networks and old mineworkings are possibly more important. Biofilms may also play a part in delaying sediment release until late in the hydrograph, and in suppressing late spring turbidity levels. Existing first-flush models appear to be an oversimplification here. Such urban headwater basin responses can provide useful insights into the generation of contaminant waves, and offer vital early-warning systems for pollution events propagating downstream.

Microbial dechlorination of polychlorinated biphenyls, dibenzo-p-dioxins, and -furans at the Portland Harbor Superfund site, Oregon, USA.

PubMed

Rodenburg, Lisa A; Krumins, Valdis; Curran, Joanna Crowe

2015-06-16

The Portland Harbor (Oregon, USA) has been declared a "Superfund" site because it is impacted by a variety of contaminants, including polychlorinated biphenyls (PCBs) and polychlorinated dibenzo-p-dioxins and -furans (PCDD/Fs). Using data collected in the remedial investigation, concentrations of PCBs and PCDD/Fs in sediment and water were examined using positive matrix factorization to look for evidence that PCBs and PCDD/Fs are dechlorinated by anaerobic bacteria. This process has long been known to occur in sediments. Recently, it has been recognized that PCB and PCDD/F dechlorination may also occur in other anaerobic environments, such as in landfills, sewers, and groundwater. The results indicate that a factor related to the dechlorination of PCBs and PCDD/Fs was present in the water but not in the sediment. Spatial patterns in dechlorination products suggest that they come primarily from groundwater. Dechlorination products comprise 22% of the PCBs in the water. The Portland Harbor therefore represents the third major US watershed in which PCBs appear to undergo dechlorination in an environment other than sediment, suggesting that the microbial dechlorination of PCBs and PCDD/Fs is more common than previously assumed. In addition, the Portland Harbor is impacted by PCBs generated inadvertently during the production of pigments, such as PCB 11, which alone exceeded the 64 pg/L federal water quality standard for the sum of PCBs in two of 120 whole water samples.

Storm Water Management Model (SWMM)

EPA Pesticide Factsheets

EPA's Storm Water Management Model (SWMM) is used throughout the world for planning, analysis and design related to stormwater runoff, combined and sanitary sewers, and other drainage systems in urban areas.

77 FR 4060 - Notice of Lodging of Second Agreement and Order Regarding Modification of the Consent Decree...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-01-26

... improve its sewage collection system including addressing Unauthorized Discharges such as sanitary sewer... used in the sewage collection system. The Department of Justice will receive for a period of thirty (30...

INEXPENSIVE DRINKING WATER CHLORINATION UNIT FOR SMALL COMMUNITIES - PHASE I

EPA Science Inventory

More than 250 drinking water systems exist for small communities in Puerto Rico that serve between 25 and 500 individuals. These water systems fall outside of the Puerto Rico Aqueduct and Sewer Authority and, thus, have insufficient water treatment systems or no water treatmen...

INEXPENSIVE DRINKING WATER CHLORINATION UNIT FOR SMALL COMMUNITIES - PHASE II

EPA Science Inventory

Over 250 drinking water systems exist for small communities in Puerto Rico that serve 25-500 individuals. These water systems fall outside of Puerto Rico Aquaduct and Sewer Authority and, thus, have no or insufficient water treatment systems. Water sources for these communit...

The effect of inclusion of inlets in dual drainage modelling

NASA Astrophysics Data System (ADS)

Chang, Tsang-Jung; Wang, Chia-Ho; Chen, Albert S.; Djordjević, Slobodan

2018-04-01

In coupled sewer and surface flood modelling approaches, the flow process in gullies is often ignored although the overland flow is drained to sewer network via inlets and gullies. Therefore, the flow entering inlets is transferred to the sewer network immediately, which may lead to a different flood estimation than the reality. In this paper, we compared two modelling approach with and without considering the flow processes in gullies in the coupled sewer and surface modelling. Three historical flood events were adopted for model calibration and validation. The results showed that the inclusion of flow process in gullies can further improve the accuracy of urban flood modelling.

Occurrence of organic wastewater-indicator compounds in urban streams of the Atlanta area, Georgia, 2003-2006

USGS Publications Warehouse

Lawrence, Stephen J.; LaFontaine, Jacob H.

2010-01-01

The similarity in the pattern and distribution of OWICs in samples at sites upstream and downstream from known CSO outfalls indicates that CSOs were not the dominant source of OWICs during the study period. Other sources may include non-sewage discharges-both permitted, permitted but out of compliance, and non-permitted, contaminated groundwater from leaking sewer lines or septic systems, sanitary-sewer overflows, or dry-weather runoff from outdoor water use. These OWICs may be better suited for identifying sewage-contaminated groundwater than sewage-contaminated surface water because groundwater is not typically affected by the OWICs that are more common in urban runoff.

Optimisation potential for a SBR plant based upon integrated modelling for dry and wet weather conditions.

PubMed

Rönner-Holm, S G E; Kaufmann Alves, I; Steinmetz, H; Holm, N C

2009-01-01

Integrated dynamic simulation analysis of a full-scale municipal sequential batch reactor (SBR) wastewater treatment plant (WWTP) was performed using the KOSMO pollution load simulation model for the combined sewer system (CSS) and the ASM3 + EAWAG-BioP model for the WWTP. Various optimising strategies for dry and storm weather conditions were developed to raise the purification and hydraulic performance and to reduce operation costs based on simulation studies with the calibrated WWTP model. The implementation of some strategies on the plant led to lower effluent values and an average annual saving of 49,000 euro including sewage tax, which is 22% of the total running costs. Dynamic simulation analysis of CSS for an increased WWTP influent over a period of one year showed high potentials for reducing combined sewer overflow (CSO) volume by 18-27% and CSO loads for COD by 22%, NH(4)-N and P(total) by 33%. In addition, the SBR WWTP could easily handle much higher influents without exceeding the monitoring values. During the integrated simulation of representative storm events, the total emission load for COD dropped to 90%, the sewer system emitted 47% less, whereas the pollution load in the WWTP effluent increased to only 14% with 2% higher running costs.

Assessment of flood hazard in a combined sewer system in Reykjavik city centre.

PubMed

Hlodversdottir, Asta Osk; Bjornsson, Brynjolfur; Andradottir, Hrund Olof; Eliasson, Jonas; Crochet, Philippe

2015-01-01

Short-duration precipitation bursts can cause substantial property damage and pose operational risks for wastewater managers. The objective of this study was to assess the present and possible future flood hazard in the combined sewer system in Reykjavik city centre. The catchment is characterised by two hills separated by a plain. A large portion of the pipes in the aging network are smaller than the current minimum diameter of 250 mm. Runoff and sewer flows were modelled using the MIKE URBAN software package incorporating both historical precipitation and synthetic storms derived from annual maximum rainfall data. Results suggest that 3% of public network manholes were vulnerable to flooding during an 11-year long rainfall sequence. A Chicago Design Storm (CDS) incorporating a 10-minute rainfall burst with a 5-year return period predicted twice as many flooded manholes at similar locations. A 20% increase in CDS intensity increased the number of flooded manholes and surface flood volume by 70% and 80%, respectively. The flood volume tripled if rainfall increase were combined with urban re-development, leading to a 20% increase in the runoff coefficient. Results highlight the need for reducing network vulnerabilities, which include decreased pipe diameters and low or drastically varying pipe grades.

Magnitude and frequency of flooding on small urban watersheds in the Tampa Bay area, west-central Florida

USGS Publications Warehouse

Lopez, M.A.; Woodham, W.M.

1983-01-01

Hydrologic data collected on nine small urban watersheds in the Tampa Bay area of west-central Florida and a method for estimating peak discharges in the study area are described. The watersheds have mixed land use and range in size from 0.34 to 3.45 square miles. Watershed soils, land use, and storm-drainage system data are described. Urban development ranged from a sparsely populated area with open-ditch storm sewers and 19% impervious area to a completely sewered watershed with 61% impervious cover. The U.S. Geological Survey natural-basin and urban-watershed models were calibrated for the nine watersheds using 5-minute interval rainfall data from the Tampa, Florida, National Weather Service rain gage to simulate annual peak discharge for the period 1906-52. A log-Pearson Type III frequency analysis of the simulated annual maximum discharge was used to determine the 2-, 5-, 10-, 25-, 50-, and 100-year flood discharges for each watershed. Flood discharges were related in a multiple-linear regression to drainage area, channel slope, detention storage area, and an urban-development factor determined by the extent of curb and gutter street drainage and storm-sewer system. The average standard error for the regional relations ranged from + or - 32 to + or - 42%. (USGS)

High spatial-temporal resolution and integrated surface and subsurface precipitation-runoff modelling for a small stormwater catchment

NASA Astrophysics Data System (ADS)

Hailegeorgis, Teklu T.; Alfredsen, Knut

2018-02-01

Reliable runoff estimation is important for design of water infrastructure and flood risk management in urban catchments. We developed a spatially distributed Precipitation-Runoff (P-R) model that explicitly represents the land cover information, performs integrated modelling of surface and subsurface components of the urban precipitation water cycle and flow routing. We conducted parameter calibration and validation for a small (21.255 ha) stormwater catchment in Trondheim City during Summer-Autumn events and season, and snow-influenced Winter-Spring seasons at high spatial and temporal resolutions of respectively 5 m × 5 m grid size and 2 min. The calibration resulted in good performance measures (Nash-Sutcliffe efficiency, NSE = 0.65-0.94) and acceptable validation NSE for the seasonal and snow-influenced periods. The infiltration excess surface runoff dominates the peak flows while the contribution of subsurface flow to the sewer pipes also augments the peak flows. Based on the total volumes of simulated flow in sewer pipes (Qsim) and precipitation (P) during the calibration periods, the Qsim/P ranges from 21.44% for an event to 56.50% for the Winter-Spring season, which are in close agreement with the observed volumes (Qobs/P). The lowest percentage of precipitation volume that is transformed to the total simulated runoff in the catchment (QT) is 79.77%. Computation of evapotranspiration (ET) indicated that the ET/P is less than 3% for the events and snow-influenced seasons while it is about 18% for the Summer-Autumn season. The subsurface flow contribution to the sewer pipes are markedly higher than the total surface runoff volume for some events and the Summer-Autumn season. The peakiest flow rates correspond to the Winter-Spring season. Therefore, urban runoff simulation for design and management purposes should include two-way interactions between the subsurface runoff and flow in sewer pipes, and snow-influenced seasons. The developed urban P-R model is useful for better computation of runoff generated from different land cover, for assessments of stormwater management techniques (e.g. the Low Impact Development or LID) and the impacts of land cover and climate change. There are some simplifications or limitations such as the runoff routing does not involve detailed sewer hydraulics, effects of leakages from water supply systems and faulty/illegal connections from sanitary sewer are not considered, the model cannot identify actual locations of the interactions between the subsurface runoff and sewer pipes and lacks parsimony.

EPA’s Stormwater Management Model (SWMM)

EPA Pesticide Factsheets

EPA’s Storm Water Management Model (SWMM) is used throughout the world for planning, analysis, and designrelated to stormwater runoff, combined and sanitary sewers, and other drainage systems in urban areas.

Systems analysis of urban wastewater systems--two systematic approaches to analyse a complex system.

PubMed

Benedetti, L; Blumensaat, F; Bönisch, G; Dirckx, G; Jardin, N; Krebs, P; Vanrolleghem, P A

2005-01-01

This work was aimed at performing an analysis of the integrated urban wastewater system (catchment area, sewer, WWTP, receiving water). It focused on analysing the substance fluxes going through the system to identify critical pathways of pollution, as well as assessing the effectiveness of energy consumption and operational/capital costs. Two different approaches were adopted in the study to analyse urban wastewater systems of diverse characteristics. In the first approach a wide ranged analysis of a system at river basin scale is applied. The Nete river basin in Belgium, a tributary of the Schelde, was analysed through the 29 sewer catchments constituting the basin. In the second approach a more detailed methodology was developed to separately analyse two urban wastewater systems situated within the Ruhr basin (Germany) on a river stretch scale. The paper mainly focuses on the description of the method applied. Only the most important results are presented. The main outcomes of these studies are: the identification of stressors on the receiving water bodies, an extensive benchmarking of wastewater systems, and the evidence of the scale dependency of results in such studies.

PRN 93-10: Effluent Discharge Labeling Statements

EPA Pesticide Factsheets

This notice describes revised effluent discharge labeling statements required on all manufacturing use products and end use products that may be discharged to waters of the United States ormunicipal sewer systems.

DECISION-SUPPORT TOOLS FOR MANAGING WASTEWATER PIPELINE PERFORMANCE IMPROVEMENTS

EPA Science Inventory

Wastewater collection systems are an extensive part of the nation's infrastructure. In the US approximately 150 million people are served by about 19,000 municipal wastewater collection systems representing about 500,000 miles of sewer pipe (not including privately owned service ...

DECISION SUPPORT TOOLS FOR MANAGING WASTEWATER PIPELINE PERFORMANCE IMPROVEMENTS

EPA Science Inventory

Wastewater collection systems are an extensive part of the nation's infrastructure. In the US approximately 150 million people are served by about 19,000 municipal wastewater collection systems representing about 500,000 miles of sewer pipe (not including privately owned service ...

ARCHITECTURAL AND CIVIL STANDARDS

DOE Office of Scientific and Technical Information (OSTI.GOV)

None

Hanford Atomic Production Operation specification guides and standards for architectural and civil engineering are presented. Information includes construction of roads, railroads, roofs, signs, buildings, building equipment, sewers, fences, safety systems, and drainage systems. Details of this manual are given in TID-4100 (Suppl.). (N.W.R.)

PROCESS DESIGN MANUAL: SURFACE DISPOSAL OF SEWAGE SLUDGE AND DOMESTIC SEPTAGE

EPA Science Inventory

Human domestic activities generate wastewater that is piped into municipal sewer systems, underground septic tanks, or portable sanitation devices. Wastewater in municipal systems is treated before being discharged into the environment, as required under the Clean Water Act. This...

Advanced Hydraulics for Operators. Training Module 1.331.3.77.

ERIC Educational Resources Information Center

Bengston, Harlan H.

This document is an instructional module package prepared in objective form for use by an instructor familiar with the application of hydraulic principles to water supply and water pollution control systems including water distribution systems and sewer systems. Included are objectives, instructor guides, student handouts and transparency masters.…

Effect and relevance of the artificial drainage system when assessing the hydrologic impact of the imperviousness distribution within the watershed

NASA Astrophysics Data System (ADS)

Thenoux, M.; Gironas, J. A.; Mejia, A.

2013-12-01

Cities and urban growth have relevant environmental and social impacts, which could eventually be enhanced or reduced during the urban planning process. From the point of view of hydrology, impermeability and natural soil compaction are one of the main problems that urbanization brings to watershed. Previous studies demonstrate and quantify the impacts of the distribution of imperviousness in a watershed, both on runoff volumes and flow, and the quality and integrity of streams and receiving bodies. Moreover, some studies have investigated the optimal distribution of imperviousness, based on simulating different scenarios of land use change and its effects on runoff, mostly at the outlet of the watershed. However, these studies typically do not address the impact of artificial drainage system associated with the imperviousness scenarios, despite it is known that storm sewer coverage affects the flow accumulation and generation of flow hydrographs. This study seeks to quantify the effects and relevance of the artificial system when it comes to assess the hydrological impacts of the spatial distribution of imperviousness and to determine the characteristics of this influence. For this purpose, an existing model to generate imperviousness distribution scenarios is coupled with a model developed to automatically generate artificial drainage networks. These models are applied to a natural watershed to generate a variety of imperviousness and storm sewer layout scenarios, which are evaluate with a morphoclimatic instantaneous unit hydrograph model. We first tested the ability of this approach to represent the joint effects of imperviousness (i.e. level and distribution) and storm sewer coverage. We then quantified the effects of these variables on the hydrological response, considering also different return period in order to take into account the variability of the precipitation regime. Overall, we show that the layout and spatial coverage of the storm sewer system affect the hydrologic response, and that these effects depend on the degree of imperviousness and the characteristics of the precipitation. Results of this research improve our understanding on how urban planning decisions can contribute to minimize the hydrologic and environmental impacts of urban development.

Flood reduction as an ecosystem service of constructed wetlands for combined sewer overflow

NASA Astrophysics Data System (ADS)

Rizzo, A.; Bresciani, R.; Masi, F.; Boano, F.; Revelli, R.; Ridolfi, L.

2018-05-01

Urban runoff negatively impacts the receiving streams and different solutions have been proposed in literature to limit the effect of urbanization on the water balance. These solutions suggest to manage urban runoff in order to switch from a post-development river hydrograph (high peak and short duration) back again to a pre-development hydrograph (low peak and high duration). Combined sewer overflows (CSOs) represent severe pollutant sources for receiving streams due to the combination of first flush of roads and sewers and black water conveyed by combined sewer systems. Constructed wetlands for CSO treatment (CSO-CWs) are adopted with increasing frequency for reducing pollutant inputs to streams. Moreover, these systems exhibit the characteristic to behave similarly to ponds, wetlands, and bioretention systems that provide flood mitigation by decreasing the intensity of peak flows. This work aims to show the additional ecosystem service provided by CSO-CWs in term of limitation of the hydraulic impact of CSO on stream hydrograph. A mathematical model is developed to simulate the hydraulic behavior of a real case study situated in Gorla Maggiore (Italy), which includes vertical flow subsurface beds (VF) as first stage and a free water surface bed (FWS) as second stage. The model simulates the unsaturated flow within VF and the accumulation of water on the top of VF and within FWS. Results show a satisfactory lamination performance of the system for both single and up to 5 consecutive flood events, with a peak flow reduction ranging from 52.7% to 95.4%. Withdrawn of flow rate from the river in order to cope with long dry period does not significantly affect the lamination performances. The considered CSO-CW exhibits an excellent lamination efficiency also during more intense floods events, with a peak flow reduction of 86.2% for a CSO event with return period of 10 years. The flow rate frequency density function determined by the CSO-CW is more shifted towards lower values compared to untreated CSOs. These results indicate that CSO-CWs work properly in terms of reduction of CSO urbanization impact on stream hydrology.

Quality of Wisconsin stormwater, 1989-94

USGS Publications Warehouse

Bannerman, Roger T.; Legg, Andrew D.; Greb, Steven R.

1996-01-01

Water-quality data were compiled from four urban stormwater monitoring projects conducted in Wisconsin between 1989 and 1994. These projects included monitoring in both storm-sewer pipes and urban streams. A total of 147 constitu ents were analyzed for in stormwater sampled from 10 storm-sewer pipes and four urban streams. Land uses represented by the storm-sewer watersheds included residential, commercial, industrial, and mixed. For about one-half the con stituents, at least 10 percent of the event mean con centrations exceeded the laboratory's minimum reporting limit. Detection frequencies were greater than 75 percent for many of the heavy metals and polycyclic aromatic hydrocarbons in both the storm sewer and stream samples, whereas detec tion frequencies were about 20 percent or greater for many of the pesticides in both types of sam ples. Stormwater concentrations for conventional constituents, such as suspended solids, chloride, total phosphorus, and fecal coliform bacteria were greater than minimum reporting limits almost 100 percent of the time. Concentrations of many of the constituents were high enough to say that stormwater in the storm sewers and urban streams might be contrib uting to the degradation of the streams. In this report, constituents defined as potential contami nants are those for which the laboratory minimum report limit was exceeded for at least 10 percent of the sampled storm events, and for which at least one event mean concentration exceeded an estab lished water-quality standard. Storm-sewer sam ples had event mean concentrations of lead, copper, zinc, cadmium, and silver that frequently exceeded Wisconsin's acute toxicity criteria for cold water fisheries. Wisconsin's human cancer criteria was exceeded almost 100 percent of the time for polycyclic aromatic hydrocarbons in stormwater samples from storm sewers and streams. Maximum concentrations of diazinon found in storm sewers exceeded recommended levels of diazinon. Storm-sewer samples also exceeded Wisconsin's ground-water enforcement standards for pesticides, PCB's, phthalates, and chloride. Defined by criteria in this report, poten tial contaminants included five metals (lead, zinc, copper, silver, and cadmium), nine polycyclic aro matic hydrocarbons, Bis(2-ethylhexyl)phthalate, four pesticides (DDT, atrazine, alachlor, and 2,4 D), suspended solids, chlorides, total phosphorus, BOD 5-day, and bacteria. Wisconsin stormwater quality was similar to stormwater quality monitored in other states. Nearly one-half of median concentrations of con stituents in Wisconsin stormwater were within 30 percent of the medians from other states. The clos est agreement was seen for biochemical oxygen demand, total phosphorus, and total recoverable zinc. Similarities in stormwater quality for the storm sewer and urban streams indicated the storm sewers were a major source of water to the streams during storm events. Concentrations of potential contaminants in urban streams increased dramati cally during storm events as compared to baseflow concentrations.

Alternative methods to trench backfill.

DOT National Transportation Integrated Search

2005-04-30

Conduit structures dealing with hydraulic drainage needs in the Louisiana highway system include pipe culverts, pipe arch culverts, storm drains, sewers, etc. Although the Louisiana Department of Transportation and Development (LADOTD) has standard s...

Toxicity and pollutant impact analysis in an urban river due to combined sewer overflows loads.

PubMed

Casadio, A; Maglionico, M; Bolognesi, A; Artina, S

2010-01-01

The Navile Channel (Bologna, Italy) is an ancient artificial water course derived from the Reno river. It is the main receiving water body for the urban catchment of Bologna sewer systems and also for the Waste Water Treatment Plant (WWTP) main outlet. The aim of this work is to evaluate the Combined Sewer Overflows (CSOs) impact on Navile Channel's water quality. In order to collect Navile flow and water quality data in both dry and wet weather conditions, two measuring and sampling stations were installed, right upstream and downstream the WWTP outflow. The study shows that even in case of low intensity rain events, CSOs have a significant effect on both water quantity and quality, spilling a considerable amount of pollutants into the Navile Channel and presenting also acute toxicity effects. The collected data shown a good correlations between the concentrations of TSS and of chemical compounds analyzed, suggesting that the most part of such substances is attached to suspended solids. Resulting toxicity values are fairly high in both measuring points and seem to confirm synergistic interactions between heavy metals.

Potentials of real time control, stormwater infiltration and urine separation to minimize river impacts: dynamic long term simulation of sewer network, pumping stations, pressure pipes and waste water treatment plant.

PubMed

Peters, C; Keller, S; Sieker, H; Jekel, M

2007-01-01

River Panke (Berlin, Germany) suffers from hydraulic peak loads and pollutant loads from separate sewers and combined sewer overflows (CSOs). Pumping the wastewater through long pressure pipes causes extreme peak loads to the wastewater treatment plant (WWTP) during stormwater events. In order to find a good solution, it is essential not to decide on one approach at the beginning, but to evaluate a number of different approaches. For this reason, an integrated simulation study is carried out, assessing the potentials of real time control (RTC), stormwater infiltration, storage and urine separation. Criteria for the assessment are derived and multi-criteria analysis is applied. Despite spatial limitations, infiltration has the highest potential and is very effective with respect to both overflows and the WWTP. Due to a high percentage of separate systems, urine separation has a similar potential and causes the strongest benefits at the WWTP. Unconventional control strategies can lead to significant improvement (comparable to infiltrating the water from approximately 10% of the sealed area).

Storage capacity and sedimentation trends of Lago Garzas, Puerto Rico, 1996-2007

USGS Publications Warehouse

Soler-Lopez, L.R.

2012-01-01

Lago Garzas is located in west-central Puerto Rico, about 3.5 kilometers southwest of the town of Adjuntas, in the confluence of the Río Vacas and three other unnamed tributaries (fig. 1). The dam is owned and operated by the Puerto Rico Electric Power Authority (PREPA), and was constructed in 1943 for hydroelectric power generation and municipal water use along the southern coast. The dam is a semi-hydraulic earthfill embankment lined with boulders, and has a height of 61.57 meters, a top width of 9.14 meters, a base width of 365.76 meters, and a crest length of 227.37 meters; State Road PR-518 crosses the top of the dam. A morning-glory-type spillway is located near the west abutment of the dam at an elevation of 736.12 meters above mean sea level (Puerto Rico Water Resources Authority, 1969). Figure 2 shows an aerial photograph of the Lago Garzas earthfill dam and the morning-glory spillway section. Additional information and operational procedures are provided in Soler-López and others (1999). During July 17-18, 2007, the U.S. Geological Survey (USGS) Caribbean Water Science Center, in cooperation with the Puerto Rico Aqueduct and Sewer Authority, conducted a bathymetric survey of Lago Garzas to update the reservoir storage capacity and update the reservoir sedimentation rate by comparing the 2007 data with the previous 1996 bathymetric survey results. The purpose of this report is to describe and document the USGS sedimentation survey conducted at Lago Garzas during July 2007, including the methods used to update the reservoir storage capacity, sedimentation rates, and areas of substantial sediment accumulation since 1996.

Predicting the Probability of Failure of Cementitious Sewer Pipes Using Stochastic Finite Element Method

PubMed Central

Alani, Amir M.; Faramarzi, Asaad

2015-01-01

In this paper, a stochastic finite element method (SFEM) is employed to investigate the probability of failure of cementitious buried sewer pipes subjected to combined effect of corrosion and stresses. A non-linear time-dependant model is used to determine the extent of concrete corrosion. Using the SFEM, the effects of different random variables, including loads, pipe material, and corrosion on the remaining safe life of the cementitious sewer pipes are explored. A numerical example is presented to demonstrate the merit of the proposed SFEM in evaluating the effects of the contributing parameters upon the probability of failure of cementitious sewer pipes. The developed SFEM offers many advantages over traditional probabilistic techniques since it does not use any empirical equations in order to determine failure of pipes. The results of the SFEM can help the concerning industry (e.g., water companies) to better plan their resources by providing accurate prediction for the remaining safe life of cementitious sewer pipes. PMID:26068092

Suitable flow pattern increases the removal efficiency of nitrogen in gravity sewers: a suitable anoxic and aerobic environment in biofilms.

PubMed

He, Qiang; Yin, Feixian; Li, Hong; Wang, Yinliang; Xu, Jingwei; Ai, Hainan

2018-03-25

The sewers have the function of carbon removal, which has been proven. But if the effect of nitrogen removal can be enhanced at the same time of carbon removal, it can lay a foundation for the realization of "sewer's working as a reactor." This paper investigated the effects of shear stress and C/N ratio on nitrogen removal through biofilms on the sewer inner wall and nitrogen transfer. The main conclusions are as follows: (1) nitrogen could be partially removed in sewers after a series of reactions; (2) the anaerobic, anoxic, aerobic environment and some bacteria related to nitrogen metabolism, which exist in the biofilm, promote the nitrification and denitrification; (3) a total of 722 functional genes involved in nitrogen metabolism were detected in the biofilm (C/N ratio of 10, shear stress of 1.4 Pa), accounting for 0.67% of all genes, and the functional genes related to denitrification were dominant. Graphical abstract ᅟ.

Impact of in-Sewer Degradation of Pharmaceutical and Personal Care Products (PPCPs) Population Markers on a Population Model.

PubMed

O'Brien, Jake William; Banks, Andrew Phillip William; Novic, Andrew Joseph; Mueller, Jochen F; Jiang, Guangming; Ort, Christoph; Eaglesham, Geoff; Yuan, Zhiguo; Thai, Phong K

2017-04-04

A key uncertainty of wastewater-based epidemiology is the size of the population which contributed to a given wastewater sample. We previously developed and validated a Bayesian inference model to estimate population size based on 14 population markers which: (1) are easily measured and (2) have mass loads which correlate with population size. However, the potential uncertainty of the model prediction due to in-sewer degradation of these markers was not evaluated. In this study, we addressed this gap by testing their stability under sewer conditions and assessed whether degradation impacts the model estimates. Five markers, which formed the core of our model, were stable in the sewers while the others were not. Our evaluation showed that the presence of unstable population markers in the model did not decrease the precision of the population estimates providing that stable markers such as acesulfame remained in the model. However, to achieve the minimum uncertainty in population estimates, we propose that the core markers to be included in population models for other sites should meet two additional criteria: (3) negligible degradation in wastewater to ensure the stability of chemicals during collection; and (4) < 10% in-sewer degradation could occur during the mean residence time of the sewer network.

ENVIRONMENTAL TECHNOLOGY VERIFICATION OF URBAN RUNOFF MODELS

EPA Science Inventory

This paper will present the verification process and available results of the XP-SWMM modeling system produced by XP-Software conducted unde the USEPA's ETV Program. Wet weather flow (WWF) models are used throughout the US for the evaluation of storm and combined sewer systems. M...

REAL-TIME CONTROL OF COMBINED SEWER NETWORKS

EPA Science Inventory

Real-time control (RTC) is a custom-designed management program for a specific urban sewerage system during a wet-weather event. The function of RTC is to assure efficient operation of the sewerage system and maximum utilization of existing storage capacity, either to fully conta...

40 CFR 35.927-3 - Rehabilitation.

Code of Federal Regulations, 2013 CFR

2013-07-01

... minor rehabilitation concurrently with the sewer system evaluation survey in any step under a grant if... consisting of major rehabilitation work may be awarded concurrently with step 2 work for the design of the...

GET REAL!

EPA Science Inventory

Combined sewer overflow (CSO) is a significant source of pollution in receiving waters. However, implementing a real-time control scheme operates automatic regulators more efficiently to maximize a collection system's storage, treatment, and transport capacities, reducing the vol...

44 CFR 206.117 - Housing assistance.

Code of Federal Regulations, 2010 CFR

2010-10-01

... owned bridge, wells and/or septic systems) damaged by a major disaster. (ii) The type of repair FEMA... home, and reconnecting or resetting mobile home sewer, water, electrical and fuel lines and tanks; and...

East Bay Municipal Utility District Settlement

EPA Pesticide Factsheets

The East Bay Municipal Utility District and its seven member communities own and operate a separate sanitary sewer system, which serves approximately 650,000 customers on the eastern side of San Francisco Bay in California.