NOAA defines coastal wetlands as all wetlands in coastal watersheds—that is, watersheds that drain into the ocean or to an estuary or bay. Although you may think of tidal salt marshes when you hear "coastal wetlands,” there are many wetlands in coastal areas that are neither tidal nor salty. Some of the most common coastal wetlands are bottomland hardwood swamps, fresh marshes, salt marshes and submerged seagrass beds (which are in fact a type of wetland). Although wetlands make up only about 4% of the Bay watershed, these 1.5 million acres of habitat serve essential functions in the ecosystem, such as acting as water filters, providing flood and erosion control, and providing habitat for fish and wildlife.

Nationwide, coastal wetlands currently make up about 30% of the wetlands in the lower 48 states, or about 27 million acres. Since the 1700s, more than half of all the wetlands in the lower 48 states have been lost. Within the Chesapeake Bay more than 60% of the historic wetlands have been lost.

Coastal wetlands losses can be traced directly to population pressures and changes along the coast. Coastal populations have increased steadily since 1970, and currently more than half the population of the United States lives in coastal counties, at densities five times greater than those of noncoastal counties. In the Bay watershed, where so much of the land is in direct contact with a stream, river, or mainstem of the Bay, population growth and associated development place enormous pressures on existing natural resources. These pressures particularly affect wetlands, which are highly vulnerable to water-flow modification, pollution, and habitat fragmentation.

The good news is that the rate of coastal wetland loss has declined over the past decades, particularly for tidal coastal wetlands such as salt marshes. Federal and state regulations governing the destruction of wetlands are partly responsible, as are community efforts to preserve existing coastal wetlands and restore damaged areas. In recent years, communities, organizations, state and federal governments, and volunteer citizens have begun to work together to save, restore, and create valuable wetland habitats, often in places that until recently were considered wastelands.

NOAA’s Chesapeake Bay Office and NOAA’s Restoration Center restore coastal wetlands through the Community-based Restoration Program. To date 12 salt marsh restoration projects have been conducted through this program in the Chesapeake Bay watershed, at sites including the Anacostia River, Bellevue in the Chesapeake Bay watershed, at sites including Fort McHenry on Baltimore Harbor, Chesapeake Bay Ecology Center in Grasonville, MD, Barren and Smith islands, and at Foxwells, Lancaster County, VA.