Knowing the locations of shipwrecks and other obstructions has always been important for safe navigation ‒ but mariners are not the only people who want to know about wrecks. They are also important for marine archeology, recreational diving, salvage operations, and fishing, among other interests. Now, Coast Survey has improved our Wrecks and Obstructions Database, giving everyone easy access to new records to explore.
Coast Survey’s wrecks and obstructions database provides info on thousands of wrecks.
Historically, Coast Survey has maintained two separate sources of information on wrecks. We recently combined the sources, bringing together information on nearly 20,000 wrecks and obstructions.
Coast Survey established the Automated Wreck and Obstruction Information System (AWOIS) database in 1981 to help estimate the level of effort required to investigate items during a planned hydrographic survey, but maritime users were also interested in AWOIS’ historical records. However, because the emphasis is on features that are most likely to pose a hazard to navigation, AWOIS has always had limitations. Most notably, AWOIS is not a comprehensive record and does not completely address every known or reported wreck. Additionally, for a number of reasons, AWOIS positions do not always agree with a charted position for a similar feature.
Coast Survey compiles NOAA’s electronic navigational charts (NOAA ENC®) from sources on features that are navigationally significant. As the official chart data used in electronic chart and display information systems (ECDIS), ENCs are the authoritative source of information about known or reported wrecks and are much more comprehensive than AWOIS. However, the features in an ENC typically lack the historic information and context provided by AWOIS.
Correcting for some overlap between the two source databases, Coast Survey’s new wrecks and obstructions database now contains information on about 13,000 wreck features and 6,000 obstructions. Wreck features from each original database are stored in separate layers but can be displayed together. Users may also choose a background map from several options.
The new database also offers users additional data formats from which to choose. Historically, shipwreck data in AWOIS was available in Adobe PDF and as Microsoft Access Database (MDB) format. More recently, KML/KMZ files replaced PDF and MDB formats, making it easier for public users to view AWOIS data, by using freely available software such as Google Maps or Google Earth. Now, in addition to KML/KMZ and Microsoft Excel formats for general users, Coast Survey provides the data in ArcGIS REST services and OGC WMS services, for use in GIS software programs or web-based map mashup sites.
In November 2013, we introduced NOAA ENC Online – a continuous viewer for our electronic navigational charts. You can click on the web map and zoom to selected features or locations, to see the information contained in over a thousand electronic charts of NOAA-charted waters. Each zoom moves you through an ENC depiction that takes into account the ENC scale and other attributes that are encoded in the ENC, allowing features to become visible or invisible as you seamlessly zoom in and out of the data.
NOAA ENC Online is based on Esri’s Maritime Chart Server.
Now this latest release of NOAA ENC Online lets you:
- Set a shallow and deep depth contour, which changes the shading to those parameters
- Set a safety contour (In electronic charting systems, the safety contour is set based on the ship’s draft changes the depiction of rocks, wrecks and obstructions to isolated dangers depending on if the water is “safe” or “unsafe” for vessel navigation.)
- Change between S-52 simplified and S-52 traditional symbols
- Change the background colors of the display based on the S-52 color palette for different light conditions on the bridge of a ship
- Turn off certain features based on different categories such as buoys and traffic routes
NOAA ENC Online is not certified for navigation. It does NOT fulfill chart carriage requirements for regulated commercial vessels under Titles 33 and 46 of the Code of Federal Regulations.
by Meredith Westington, Coast Survey geographer
Good, informed decisions are often based on analyses of historic and present conditions. Researchers, decision-makers, and amateur history buffs find detailed documentation of past conditions in the thousands of Coast Survey charts, dating back to the mid-1800s, in our Historical Map and Chart Collection.
Just like present day nautical charts, historic charts contain a wealth of information about geographic features — including their names, shape, and condition. Geographic names are important locational references for today’s emergency responders, but current and historic names also convey important aspects of local people and culture, which may persist through time.
As Coast Survey’s nautical cartographers routinely apply new topographic and hydrographic data to improve decisions at-sea, a question arises about names when a geographic feature, such as an island, bay, or bayou, has changed: does the associated place name disappear when the geographic feature is no longer there, or does the local population still use the historic name to convey a shared sense of place?
Coast Survey cartographers raised this exact question after applying new shoreline information to charts covering Louisiana. When cartographers applied new shoreline data to charts 11358 and 11364 in 2011, they found that named features were no longer there (see the images below for a comparison of today’s landforms vs. the historic landforms in 1965). In early 2013, another new shoreline survey similarly affected fourteen geographic names on chart 11361. They removed these “dangling names” to reduce chart clutter, but are there new names for the areas where the features used to be?
Losing places (and their names) may mean losing important locational references. Some of these places have appeared on NOAA’s nautical charts of Louisiana since the late 1800s, so their removal raises concerns about a loss of cultural identity on the landscape. For example, Cyprien Bay was named for longtime resident Cyprien Buras. The names live on, of course, on the historic maps and charts in Coast Survey’s Historical Map and Chart Collection. Importantly, they are also retained in the lesser-known U.S. Board on Geographic Names’ federal repository of place names, the Geographic Names Information System. The system’s current and historical records make a great starting point for finding names that you can use to locate relevant historical nautical charts in the Historical Map and Chart Collection. The collection has an easy-to-use geographic place name search function. Just type in a name, and start to explore our nation’s geographic changes…
Search over 35,000 historical maps and charts, just using a geographical name.