view counter

Every Foot of Our Shoreline Counts

It’s all counted in Chesapeake Bay Coastal Inventory


      “To keep every cog and wheel is the first precaution of intelligent tinkering,” conservationist Aldo Leopold’s advised.

     In applying that precaution to Chesapeake Bay, the Virginia Institute of Marine Sciences has inventoried 60 million linear feet of tidal shoreline. Bay waters meet almost 7,500 miles of land in Virginia and 4,000 in Maryland.

     Accounted for are every beach, breakwater, bulkhead, boathouse, ramp, dock, jetty, living shoreline, marina, mud flat, oyster reef, tidal marsh and tree-lined bank.

     The inventory began back in the 1970s with researchers making observations and trying to document precise locations from a boat cruising along the shoreline. Global positioning systems developed in the 1980s and 1990s made the job much more efficient. 

     In the beginning, specialists spent thousands of hours at lighted digitizing tables covered with Mylar sheets or aerial photographs, using precision cursors to register GPS coordinates and map tidal wetlands boundaries.

     As GPS units improved, so did the quality of aerial imagery. By the mid-2000s, digital imagery had become so detailed that field mapping was no longer necessary. Now most of the mapping is done on a computer with aerial imagery rather than by cruising along the shore by boat. 

     Today’s imagery is so detailed that “we can see driveways and cars and sometimes individual boulders,” says Marcia Berman, who began work on the mapping project in 1989 and is now the director of the VIMS comprehensive coastal inventory program. “You could even count the number of rocks in a breakwater.”

     The massive Chesapeake Bay Coastal Inventory also provides interactive tools where you can view each aquaculture site, conservation easement, oyster lease and underwater grass bed. 

      Another part of the inventory is a model-based recommendation for maximizing shoreline health. The model prefers living shorelines and provides links to best management practices.

     The impetus for this amazing document was the Tidal Wetlands Act of 1972. Alarmed by widespread dredging and filling of coastal marshes, Virginia’s General Assembly passed the legislation to prevent “despoliation and destruction” of wetlands and “to accommodate necessary economic development in a manner consistent with wetlands preservation.”

     A mandate from the legislature to inventory wetlands grew into the comprehensive survey of the shoreline. 

     Two more laws — Virginia’s Dunes and Beaches Act in 1980 and Chesapeake Bay Preservation Act in 1988 — expanded protection to the Commonwealth’s sandy beaches, bluffs and coastal uplands. 

      All that knowledge has everyday, real-world consequences. All 44 coastal localities in Virginia regularly use it to make management decisions. It’s cited every time a property owner submits a permit to the local Wetlands Board seeking to build a dock or protect a shoreline. It’s used again as each county updates its comprehensive plan. 

      The Chesapeake Bay Coastal Inventory ranks as a world first.

     It’s been imitated throughout the region and across the nation.

      Recognizing the inventory’s value, Maryland contracted with VIMS to update maps of all of its Chesapeake Bay tidal shoreline. The Maryland Shoreline Inventory resurvey of nearly 2,000 miles of tidal shoreline began this year, using remote desktop mapping techniques. It’s expected to be finished next year.

      The approach also has been adopted by localities in Delaware and North Carolina. Beyond our own region, VIMS is partnering with NOAA on a multi-year project in the Gulf of Mexico using an inventory-based model that will soon help guide management action in Texas, Alabama, Louisiana and Florida. 

      “We’ve seen recent use by the Navy, NOAA’s Coastal Zone Management program, the EPA, the Army Corps of Engineers, the U.S. Geological Survey, the U.S. Fish and Wildlife Service and by NGOs like The Nature Conservancy,” Berman says.

     Take a look at