Sample records for wharves

  1. 33 CFR 127.103 - Piers and wharves.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... facility handling LNG is in a region subject to earthquakes, the piers and wharves must be designed to resist earthquake forces. (b) Substructures, except moorings and breasting dolphins, that support or are...

  2. 33 CFR 127.103 - Piers and wharves.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... facility handling LNG is in a region subject to earthquakes, the piers and wharves must be designed to resist earthquake forces. (b) Substructures, except moorings and breasting dolphins, that support or are...

  3. 33 CFR 127.103 - Piers and wharves.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... facility handling LNG is in a region subject to earthquakes, the piers and wharves must be designed to resist earthquake forces. (b) Substructures, except moorings and breasting dolphins, that support or are...

  4. 33 CFR 127.103 - Piers and wharves.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... facility handling LNG is in a region subject to earthquakes, the piers and wharves must be designed to resist earthquake forces. (b) Substructures, except moorings and breasting dolphins, that support or are...

  5. 33 CFR 127.103 - Piers and wharves.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... facility handling LNG is in a region subject to earthquakes, the piers and wharves must be designed to resist earthquake forces. (b) Substructures, except moorings and breasting dolphins, that support or are...

  6. 33 CFR 162.90 - White River, Arkansas Post Canal, Arkansas River, and Verdigris River between Mississippi River...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Mississippi River Ark., and Catoosa, Okla. (2) Bridges, wharves and other structures. All bridges, wharves, and other structures in or over the waterways described in paragraph (a)(1) of this section. (3... their not being drawn away from the bank by winds, currents, or the suction of passing vessels. Towlines...

  7. 33 CFR 162.90 - White River, Arkansas Post Canal, Arkansas River, and Verdigris River between Mississippi River...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Mississippi River Ark., and Catoosa, Okla. (2) Bridges, wharves and other structures. All bridges, wharves, and other structures in or over the waterways described in paragraph (a)(1) of this section. (3... their not being drawn away from the bank by winds, currents, or the suction of passing vessels. Towlines...

  8. 26 CFR 1.263A-8 - Requirement to capitalize interest.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... must include anticipated expense and time for delay, rework, change orders, and technological, design..., roads, bridges, tunnels, paved parking areas and other pavements, special foundations, wharves and docks...

  9. Production and marketing of wood piling and poles in the Northeast

    Treesearch

    Myron D. Ostrander

    1953-01-01

    Since the earliest colonial settlements along the northeastern seaboard, wood piling has been used for wharves and piers and other waterfront structures. As waterside industries and waterborne commerce grew, the demand for wood piling grew.

  10. 26 CFR 1.897-1 - Taxation of foreign investment in United States real property interests, definition of terms.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... parking areas and other pavements, special foundations for heavy equipment, wharves and docks, bridges... to real property; (2) Whether the property was designed to be easily removable or to remain in place...

  11. 26 CFR 1.897-1 - Taxation of foreign investment in United States real property interests, definition of terms.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... parking areas and other pavements, special foundations for heavy equipment, wharves and docks, bridges... to real property; (2) Whether the property was designed to be easily removable or to remain in place...

  12. 26 CFR 1.897-1 - Taxation of foreign investment in United States real property interests, definition of terms.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... parking areas and other pavements, special foundations for heavy equipment, wharves and docks, bridges... to real property; (2) Whether the property was designed to be easily removable or to remain in place...

  13. 26 CFR 1.897-1 - Taxation of foreign investment in United States real property interests, definition of terms.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... parking areas and other pavements, special foundations for heavy equipment, wharves and docks, bridges... to real property; (2) Whether the property was designed to be easily removable or to remain in place...

  14. 26 CFR 1.897-1 - Taxation of foreign investment in United States real property interests, definition of terms.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... parking areas and other pavements, special foundations for heavy equipment, wharves and docks, bridges... to real property; (2) Whether the property was designed to be easily removable or to remain in place...

  15. 46 CFR Section 1 - Definitions.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... agreement to exercise delegated authorities of the Director, NSA, in the control of operations of a... location in a port where passengers or commodities are transferred between land and water carriers or between two water carriers, specifically including: wharves, piers, sheds, warehouses, yards, and docks...

  16. 33 CFR 162.40 - Inland waterway from Delaware River to Chesapeake Bay, Del. and Md. (Chesapeake and Delaware Canal).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... avoid damage by suction or wave wash to wharves, landings, riprap protection, or other boats, or injury... suction or wave wash does occur. Owners and operators of yachts, motorboats, rowboats and other craft are...

  17. 33 CFR 162.40 - Inland waterway from Delaware River to Chesapeake Bay, Del. and Md. (Chesapeake and Delaware Canal).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... avoid damage by suction or wave wash to wharves, landings, riprap protection, or other boats, or injury... suction or wave wash does occur. Owners and operators of yachts, motorboats, rowboats and other craft are...

  18. 33 CFR 162.40 - Inland waterway from Delaware River to Chesapeake Bay, Del. and Md. (Chesapeake and Delaware Canal).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... avoid damage by suction or wave wash to wharves, landings, riprap protection, or other boats, or injury... suction or wave wash does occur. Owners and operators of yachts, motorboats, rowboats and other craft are...

  19. 33 CFR 162.40 - Inland waterway from Delaware River to Chesapeake Bay, Del. and Md. (Chesapeake and Delaware Canal).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... avoid damage by suction or wave wash to wharves, landings, riprap protection, or other boats, or injury... suction or wave wash does occur. Owners and operators of yachts, motorboats, rowboats and other craft are...

  20. Environmental Enhancements and Navigation Infrastructure: A Study of Existing Practices, Innovative Ideas, Impediments, and Research Needs

    DTIC Science & Technology

    2011-07-01

    velocity/substrate Excavate back channels in river systems Piers & Wharves Design hard structures to facilitate better seaweed recruitment...allows vegetative colonization of areas beneath the structures P Design hard structures to facilitate better seaweed recruitment I Provide

  1. 75 FR 49017 - America's Marine Highway Grant Notice of Funding Availability

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-12

    ... provide public benefit by transporting passengers and/or freight (container or wheeled) in support of all... infrastructure (wharves, docks, terminals, paving, etc.), --Cargo, passenger and/or vessel handling equipment... and keeping track of entities receiving Federal funds. The identifier is used for tracking purposes...

  2. 33 CFR 126.3 - Definitions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... permit is required under 33 CFR 126.17. (2) Ammonium nitrate products, division 5.1 (oxidizing) materials... piers, wharves, and similar structures to which a vessel may be secured; areas of land, water, or land and water under and in the immediate proximity to these structures; buildings on or contiguous to...

  3. 33 CFR 6.01-4 - Waterfront facility.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Waterfront facility. 6.01-4... PROTECTION AND SECURITY OF VESSELS, HARBORS, AND WATERFRONT FACILITIES Definitions § 6.01-4 Waterfront facility. Waterfront facility. “Waterfront facility,” as used in this part, means all piers, wharves, docks...

  4. Strong Motion Instrumentation of Seismically-Strengthened Port Structures in California by CSMIP

    USGS Publications Warehouse

    Huang, M.J.; Shakal, A.F.

    2009-01-01

    The California Strong Motion Instrumentation Program (CSMIP) has instrumented five port structures. Instrumentation of two more port structures is underway and another one is in planning. Two of the port structures have been seismically strengthened. The primary goals of the strong motion instrumentation are to obtain strong earthquake shaking data for verifying seismic analysis procedures and strengthening schemes, and for post-earthquake evaluations of port structures. The wharves instrumented by CSMIP were recommended by the Strong Motion Instrumentation Advisory Committee, a committee of the California Seismic Safety Commission. Extensive instrumentation of a wharf is difficult and would be impossible without the cooperation of the owners and the involvement of the design engineers. The instrumentation plan for a wharf is developed through study of the retrofit plans of the wharf, and the strong-motion sensors are installed at locations where specific instrumentation objectives can be achieved and access is possible. Some sensor locations have to be planned during design; otherwise they are not possible to install after construction. This paper summarizes the two seismically-strengthened wharves and discusses the instrumentation schemes and objectives. ?? 2009 ASCE.

  5. Corrosion Potential Monitoring for Polymer Composite Wrapping and Galvanic CP System for Reinforced Concrete Marine Piles

    DTIC Science & Technology

    2010-02-01

    deteriorated – Rebar corrosion – Spalling concrete Repair Options • Patching • Polymeric composite wraps • Pre-fabricated composite shell with CP Objective... Corrosion Potential Monitoring for Polymer Composite Wrapping and Galvanic CP System for Reinforced Concrete Marine Piles David Bailey, Richard...Command DoD Corrosion Problem • Piers and wharves – Critical facilities – $14.5M maintenance costs – Reinforced concrete piles • Aged and

  6. Annual Report Fiscal Year 2003 of the Secretary of the Army on Civil Works Activities (1 October 2002 - 30 September 2003)

    DTIC Science & Technology

    2004-07-29

    Terminal facilities. Wharves suitable for landing or loading are at Bath, Woolwich, Richmond , Randolph, Gardiner, Hallowell and Augusta. Rail...RI 1882 5,000 50 - Provincetown Harbor, MA 5 1997 3,889,577 1,053,966 797,847 Richmond Harbor, ME 4 1883 20,000 - - Richmond’s Island Harbor...through Philadelphia Harbor along east side of channel and Port Richmond anchorage to 37 feet deep, except for that portion of channel which forms a

  7. Dynamic characteristics and simplified numerical methods of an all-vertical-piled wharf in offshore deep water

    NASA Astrophysics Data System (ADS)

    Zhang, Hua-qing; Sun, Xi-ping; Wang, Yuan-zhan; Yin, Ji-long; Wang, Chao-yang

    2015-10-01

    There has been a growing trend in the development of offshore deep-water ports in China. For such deep sea projects, all-vertical-piled wharves are suitable structures and generally located in open waters, greatly affected by wave action. Currently, no systematic studies or simplified numerical methods are available for deriving the dynamic characteristics and dynamic responses of all-vertical-piled wharves under wave cyclic loads. In this article, we compare the dynamic characteristics of an all-vertical-piled wharf with those of a traditional inshore high-piled wharf through numerical analysis; our research reveals that the vibration period of an all-vertical-piled wharf under cyclic loading is longer than that of an inshore high-piled wharf and is much closer to the period of the loading wave. Therefore, dynamic calculation and analysis should be conducted when designing and calculating the characteristics of an all-vertical-piled wharf. We establish a dynamic finite element model to examine the dynamic response of an all-vertical-piled wharf under wave cyclic loads and compare the results with those under wave equivalent static load; the comparison indicates that dynamic amplification of the structure is evident when the wave dynamic load effect is taken into account. Furthermore, a simplified dynamic numerical method for calculating the dynamic response of an all-vertical-piled wharf is established based on the P-Y curve. Compared with finite element analysis, the simplified method is more convenient to use and applicable to large structural deformation while considering the soil non-linearity. We confirmed that the simplified method has acceptable accuracy and can be used in engineering applications.

  8. Corrosion control for reinforced concrete

    NASA Astrophysics Data System (ADS)

    Torigoe, R. M.

    The National Bureau of Standards has recorded that in 1975 the national cost of corrosion was estimated at $70 billion. Approximately 40% of that total was attributed to the corrosion of steel reinforcements in concrete. Though concrete is generally perceived as a permanent construction material, cracking and spalling can occur when corrosion of steel reinforcements progresses to an advanced stage. This problem frequently occurs in reinforced concrete highway bridge decks, wharves, piers, and other structures in marine and snowbelt environments. Since concrete has a very low tensile strength, steel reinforcements are added to carry the tensile load of the composite member. Corrosion reduces the effective diameter of the reinforcements and, therefore, decreases the load carrying capability of the member. Though the corrosion process may occur in various forms and may be caused by different sources, the ultimate result is still the failure of the reinforced concrete.

  9. Earth Observations taken by the Expedition Seven crew

    NASA Image and Video Library

    2003-07-27

    ISS007-E-10960 (27 July 2003) --- Alexandria, Egypt, is featured in this image photographed by an Expedition 7 crewmember on the International Space Station (ISS). Founded by Alexander the Great in 331 BC on the Mediterranean coast of Egypt, Alexandria became a center of trade and learning in the ancient world. Alexander built the causeway between the Eastern and Western Harbors, joining Pharos Island to the mainland. Alexandria’s cultural status was symbolized by the lighthouse on Pharos, one of the “Seven Wonders of the World.” The causeway is still known as the old part of the modern city. Since the year 2000, underwater archeologists have located the sunken palace, ceremonial buildings and port facilities of ancient Alexandria, located along most of the curved southern shoreline of the Eastern Harbor. This detailed image provides a view of the modern port facilities in the Western Harbor, where wharves and many moored ships can be detected.

  10. Seismic Risk Assessment of Italian Seaports Using GIS

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

    Bartolomei, Anna; Corigliano, Mirko; Lai, Carlo G.

    Seaports are crucial elements in the export and import of goods and/or on the flow of travellers in the tourism industry of many industrialised nations included Italy. Experience gained from recent earthquakes (e.g. 1989 Loma Prieta in USA, 1995 Hyogoken-Nanbu and 2003 Tokachi-Oki in Japan) have dramatically demonstrated the seismic vulnerability of seaport structures and the severe damage that can be caused by ground shaking. In Italy, the Department of Civil Protection has funded a research project to develop a methodology for the seismic design of new marginal wharves and assessment of existing structures at seaports located in areas ofmore » medium or high seismicity. This paper shows part of the results of this research project, currently underway, with particular reference to the seismic risk assessment through an interactive, geographically referenced database (GIS). Standard risk assessment have been carried out for the Gioia Tauro port in Calabria (Italy) using the empirical curves implemented by the National Institute of Building Sciences (NIBS, 2004)« less

  11. Propagule pressure determines recruitment from a commercial shipping pier.

    PubMed

    Hedge, Luke H; Johnston, Emma L

    2012-01-01

    Artificial structures associated with shipping and boating activities provide habitats for a diverse suite of non-indigenous marine species. Little is known about the proportion of invader success in nearby waters that is attributable to these structures. Areas close to piles, wharves and piers are likely to be exposed to increasing levels of propagule pressure, enhancing the recruitment of non-indigenous species. Recruitment of non-indigenous and native marine biofouling taxa were evaluated at different distances from a large commercial shipping pier. Since artificial structures also represent a desirable habitat for fish, how predation on marine invertebrates influences the establishment of non-indigenous and native species was also evaluated. The colonisation of several non-indigenous marine species declined rapidly with distance from the structure. Little evidence was found to suggest that predators have much influence on the colonisation success of marine sessile invertebrate species, non-indigenous or otherwise. It is suggested that propagule pressure, not predation, more strongly predicts establishment success in these biofouling assemblages.

  12. Occurrence, source analysis and risk assessment of androgens, glucocorticoids and progestagens in the Hailing Bay region, South China Sea.

    PubMed

    Liu, Shan; Chen, Hui; Zhou, Guang-Jie; Liu, Shuang-Shuang; Yue, Wei-Zhong; Yu, Shen; Sun, Kai-Feng; Cheng, Hefa; Ying, Guang-Guo; Xu, Xiang-Rong

    2015-12-01

    The occurrence and spatial distribution of 40 steroids in the environmental matrices of the Hailing Bay region, South China Sea, were investigated by rapid resolution liquid chromatography-tandem mass spectrometry (RRLC-MS/MS). Seventeen, 14 and 11 of 40 steroids were detected with the concentrations ranging from 0.04 (testosterone) to 40.00 ng/L (prednisolone), 1.33 (4-hydroxy-androst-4-ene-17-dione) to 1855 ng/L (androsta-1,4-diene-3,17-dione) and <0.19 (androsta-1,4-diene-3,17-dione) to 2.37 ng/g (progesterone) in the seawater, the municipal sewage discharged effluent and the sediment samples, respectively. The concentrations and risk quotients (RQs) of the steroids detected in the water samples decreased in the order of municipal sewage discharge site>wharves~aquaculture zones~tourism areas>offshore areas. The distribution of steroids in the marine environment was significantly correlated with the levels of chemical oxygen demand (COD) and ammonium nitrogen (NH4-N). Source analysis indicated that untreated municipal sewage was the main source of steroids in the marine environment. Furthermore, progesterone was found to be a reliable chemical indicator to surrogate different steroids in both the water and sediment phases based on the correlation analysis. Copyright © 2015 Elsevier B.V. All rights reserved.

  13. Protocols for Image Processing based Underwater Inspection of Infrastructure Elements

    NASA Astrophysics Data System (ADS)

    O'Byrne, Michael; Ghosh, Bidisha; Schoefs, Franck; Pakrashi, Vikram

    2015-07-01

    Image processing can be an important tool for inspecting underwater infrastructure elements like bridge piers and pile wharves. Underwater inspection often relies on visual descriptions of divers who are not necessarily trained in specifics of structural degradation and the information may often be vague, prone to error or open to significant variation of interpretation. Underwater vehicles, on the other hand can be quite expensive to deal with for such inspections. Additionally, there is now significant encouragement globally towards the deployment of more offshore renewable wind turbines and wave devices and the requirement for underwater inspection can be expected to increase significantly in the coming years. While the merit of image processing based assessment of the condition of underwater structures is understood to a certain degree, there is no existing protocol on such image based methods. This paper discusses and describes an image processing protocol for underwater inspection of structures. A stereo imaging image processing method is considered in this regard and protocols are suggested for image storage, imaging, diving, and inspection. A combined underwater imaging protocol is finally presented which can be used for a variety of situations within a range of image scenes and environmental conditions affecting the imaging conditions. An example of detecting marine growth is presented of a structure in Cork Harbour, Ireland.

  14. A new species of Monstrilla Dana, 1849 (Copepoda: Monstrilloida: Monstrillidae) from Korea, including a key to species from the north-west Pacific.

    PubMed

    Lee, Jimin; Chang, Cheon Young

    2016-10-11

    A new species of monstrilloid copepod belonging to the genus Monstrilla Dana, 1849 is recorded from South Korea. Specimens were obtained between May of 2012 and January of 2014 from inshore waters along the coasts of the East Sea, South Sea, and Jeju Island, using a light trap installed at quays and wharves overnight. Monstrilla ilhoii sp. nov. is characterized by a remarkable combination of a large body size (females about 3.8 mm long, males about 2.8 mm long), a polygonal ridge pattern (cuticular reticulation) over the entire body surface, and an antennule armature featuring a supernumerary spiniform seta (4d3) in females and a dagger-shaped distal spine (62) in both sexes. In other respects M. ilhoii sp. nov. most closely resembles M. lata Desai & Bal, 1963; both species have one and three setae on the endopodal and exopodal lobes, respectively, of female leg 5, a horseshoe-shaped male genital apparatus with marked undulations along the whole distal margin, and six setae on each caudal ramus in both sexes. This paper provides a description of the new species, taxonomic remarks on its morphological features, and differential diagnoses with respect to its allies. Scanning electron microscopy was used to document significant morphological microcharacters. The species of Monstrilla known from five sub-regions of the north-west Pacific are enumerated with the source references, and keys to the females and males of these species are provided.

  15. Earth Observations taken by the Expedition 39 Crew

    NASA Image and Video Library

    2014-05-05

    ISS039-E-018541 (5 May 2014) --- New York City is featured in this image photographed by an Expedition 39 crew member on the International Space Station. This detailed image reveals the narrow shape of Manhattan located between the Hudson River and the East River, a feature familiar to crews on the space station. The ragged line of shadow cast by the Palisades cliff crosses the bottom of the image. Wharves jut into the rivers; bridges are visible mainly because of the shadows they cast, and the grid pattern of major roads stands out. On the island of Manhattan itself the main visual features are Central Park (with playing fields as white dots) and two darker zones where the tallest buildings in Midtown East and the Financial District cast strong shadows, even in this early afternoon view. Rivers and parks reduce the effect of the urban heat island – the local zone of higher surface and atmospheric temperatures generated by storage and later release of heat by city materials such as concrete and tarmac. Rivers provide pathways for wind and the cooling effect of parks is detectable by instruments on spacecraft that can measure the temperature of the ground surface. Tall buildings have a more complex effect. Shadowed zones in the "urban canyons" between tall buildings – as shown in this image – receive fewer hours of direct sun per day. But where the sun can reach canyon floors, the sun's energy is reflected back up at the walls of the buildings where it is absorbed and later released as heat. This is especially the case at night when urban canyons retain more heat than those sections of the city with shorter buildings.

  16. The Swedish Bohus granite - a stone with a fascinating history

    NASA Astrophysics Data System (ADS)

    Schouenborg, Björn; Eliasson, Thomas

    2015-04-01

    One of the most well-known and well spread Swedish stone types used as building stones is the Bonus granite. It outcrops in an area north of Gothenburgh (SW Sweden), along the coastline, approximately 35 km wide and 85 km long. The granite continues into Norway as the Iddefjord granite. The Bohus granite is one of Sweden's youngest granites. Isotopic dating shows that the magma cooled at about 920 M years ago and thus marking the end of the Sveconorwegian orogoney. It is a composite granite massif area with several granitic intrusions but with rather homogeneous mineralogy. However, colour and texture varies quite a lot and the colour ranges from red to reddish grey although some pure grey varieties occur sparsely. The grain size ranges from medium grained to coarse grained and even with some porphyric parts. Quarrying in an industrial scale started 1842. The merchant A C Kullgren opened the first quarry and produced stones for the construction of the 86 km long Trollhättan channel connecting lake Vänern and the Atlantic ocean in the SW Sweden The stone was used for constructing harbors and wharves along the channel. Several quarries opened in the late 1800 around 1870 - 1890 and the export increased steadily with deliveries to Germany, Denmark, Holland, England and even to South America. The stone industries in Bohuslän (Bohus county), at its peak in 1929, engaged around 7 000 employees. During the depression in 1930 almost all of them became unemployed. However, as a curiosity, production and export continued to Germany for construction of Germania, the future World capital city ("Welthauptstadt Germania"), planned by Adolf Hitler and Albert Speer. About 500 stone workers were kept employed for this project during the late thirties. Today several varieties are still produced: Evja/Ävja, Tossene, Brastad, Näsinge, Broberg, Nolby, Allemarken and Skarstad. However, the number of stone workers is far from that of the early 1900. The Swedish production is mainly blocks but also paving products like sets, slabs and kerb stones are still manufactured in Sweden. Blocks are generally further processed in other countries like Italy and China to reach the European market as semi-finished products like slabs or finished products for any kind of application. The granite is very durable and suitable for all types of natural stone products.

  17. Comparison of Shallow Survey 2012 Multibeam Datasets

    NASA Astrophysics Data System (ADS)

    Ramirez, T. M.

    2012-12-01

    The purpose of the Shallow Survey common dataset is a comparison of the different technologies utilized for data acquisition in the shallow survey marine environment. The common dataset consists of a series of surveys conducted over a common area of seabed using a variety of systems. It provides equipment manufacturers the opportunity to showcase their latest systems while giving hydrographic researchers and scientists a chance to test their latest algorithms on the dataset so that rigorous comparisons can be made. Five companies collected data for the Common Dataset in the Wellington Harbor area in New Zealand between May 2010 and May 2011; including Kongsberg, Reson, R2Sonic, GeoAcoustics, and Applied Acoustics. The Wellington harbor and surrounding coastal area was selected since it has a number of well-defined features, including the HMNZS South Seas and HMNZS Wellington wrecks, an armored seawall constructed of Tetrapods and Akmons, aquifers, wharves and marinas. The seabed inside the harbor basin is largely fine-grained sediment, with gravel and reefs around the coast. The area outside the harbor on the southern coast is an active environment, with moving sand and exposed reefs. A marine reserve is also in this area. For consistency between datasets, the coastal research vessel R/V Ikatere and crew were used for all surveys conducted for the common dataset. Using Triton's Perspective processing software multibeam datasets collected for the Shallow Survey were processed for detail analysis. Datasets from each sonar manufacturer were processed using the CUBE algorithm developed by the Center for Coastal and Ocean Mapping/Joint Hydrographic Center (CCOM/JHC). Each dataset was gridded at 0.5 and 1.0 meter resolutions for cross comparison and compliance with International Hydrographic Organization (IHO) requirements. Detailed comparisons were made of equipment specifications (transmit frequency, number of beams, beam width), data density, total uncertainty, and IHO compliance. Results from an initial analysis indicate that more factors need to be considered to properly compare sonar quality from processed results than just utilizing the same vessel with the same vessel configuration. Survey techniques such as focusing the beams over a narrower beam width can greatly increase data quality. While each sonar manufacturer was required to meet Special Order IHO specifications, line spacing was not specified and allowed for a greater data density despite equipment specification.

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