Historical Information

Prior to conducting a survey, several steps should be taken to ensure a successful operation. All available information about the area should be obtained from up-to-date sources. Further information on NOAA bathymétrie products is provided in Appendix E. Appendix A provides a list of addresses for relevant sources. Appendix C provides usefiil suggestions for site sur veys. This information includes previous surveys of the area:

• Nautical charts from NOAA - a set of five catalogs is available from NOAA :

- Catalog 1. U.S. Atlantic and Gulf Coasts; including Puerto Rico and the Virgin Islands

- Catalog 2. U.S. Pacific Coast; including Hawaii, Guam, and the Samoa Islands

- Catalog 3. Alaska and Aleutian Islands

- Catalog 4. Great Lakes and adjacent waterways

- Catalog 5. United States Bathymétrie and Fishing Maps

In addition, dates of latest editions (issued quarterly) should be consulted to verify that current maps/charts are being used.

• National Ocean Survey (NOS) (formerly United States Geological Survey (USGS)) topographic charts - both 7.5- and 15-minute series. These are land topography maps that provide good detail of the local area roads. This series also shows the location of selected control points. These come in several types:

- Topographic maps

- Topographic bathymétrie maps

- Land use and land cover maps

- Orthophotoquads

- Orthophotomaps

These products are available from:

• NOAA tide tables are published for:

- Europe and West Coast of Africa (including Mediterranean Sea)

- East Coast, North and South America (including Greenland)

- West Coast, North and South America (including Hawaiian Islands)

- Central and Western Pacific Ocean and Indian Ocean

• NOAA tidal current tables and tidal current charts.

• NOAA United States Coastal Pilots are published for:

Atlantic Coast

- Eastport to Cape Cod

- Cape Code to Sandy Hook

- Sandy Hook to Cape Henry

- Cape Henry to Key West

- Gulf of Mexico, Puerto Rico, and Virgin Islands

Pacific Coast

- California, Oregon, Washington, and Hawaii

- Alaska, Dixon Entrance to Cape Spencer

- Alaska, Cape Spencer to Beaufort Sea

• The Coastal Pilots supplement the navigational information shown on the nautical charts.

• The following Defense Mapping Agency publications may be helpful (addresses in Appendix A):

- Guide to Marine Observing and Reporting - Publication 60C

- Sailing Guides (both planing and enroute guides)

- Fleet Guide (if site is near a major harbor)

• Existing Public Works drawings.

• Construction drawings for new facilities.

• Previous inspection reports, etc.

In addition, all available information on local tides, currents, winds, temperature, visibility, and daylight hours should be obtained. When practical, interviews with local fishermen, boaters, and nearshore residents can provide valuable background information for the survey (see Section 1.4).

The extent of the survey can be dictated by existing information. If a recent survey has been performed by another party, a rudimentary check of the existing survey's information could be all that is necessary to satisfy the job requirements. It is possible to gather all of the needed information without "going to the field. "

4.2.2 Presurvey Decisions

A successful operation requires preparing a well thought-out plan for doing the survey. Decisions must be made early in the planning process as to what types of data are to be obtained. These decisions fall into the general areas of:

• Objectives of the survey

• Areal extent of the survey

• Horizontal control and accuracy required

• Navigation method

• Vertical control, contour interval, and accuracy requirements

• Geophysical data requirements

• Geotechnical data requirements

• Data logging requirements

• Data reduction requirements

• Data processing requirements

• Final report requirements

These decisions will influence the equipment required & well as the manpower and time required to perform the work.

In geographical locations where the team has not previously worked, a pre survey site visit is generally in order. This will aid in logistics planning and will allow the advanced party to determine site specific information. Use the site visit to gather information from local sources, such as fishermen, harbor masters, and local Coast Guard personnel. If any schools or universities in the area have oceanography, ocean engineering, geology, geotechnical, or geophysical programs, a recommend that someone visit the department.

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