Climate Change, Sea-Level Rise, and the Chesapeake Bay

In 2010 the last remaining house on Holland Island off the coast of southern Dorchester County was subsumed by the Chesapeake Bay. The former residents left long ago in 1918 when erosion and rising water levels forced the once thriving town of watermen and their families to move to the mainland. The vulnerability of the Delmarva peninsula, which has been slowly sinking since the last Ice Age, makes it a startling early warning case study in climate change sea-level rise. Scientific data indicates that troublesome flooding dismissed by some as the natural ebb and flow of water levels portends coming problems for settlement in low-lying coastal areas. Where previously it took 1,000 years for the Bay’s water levels to rise three feet, they rose over a foot between 1900 and 2000, and scientists fear a rise of another two to three feet by 2100. The long Chesapeake coastline of Maryland is especially vulnerable, with places like Talbot County consisting of 600 miles of tidal shoreland, the longest in the country. Low-lying islands have slowly been swallowed by the Bay over the decades, but now rising water levels threaten landmasses such as Smith Island. 

The response varies. Annapolis is trying to launch an ambitious series of flood control measures to protect its historic core, including floodgates, pumps, and seawalls. Smaller and less affluent communities face property values that are literally underwater and bide their time until relocation is possible, perhaps with government assistance. Others deny that anything extraordinary or human caused is happening, pointing to historic floods and personal experience. This view is aided by the fact that climate change–related sea level rise has been documented on the Eastern Shore since the mid-nineteenth century. Larger-scale efforts by government agencies and environmental groups such as the Chesapeake Bay Foundation take a more holistic approach to water quality and watershed management for the Bay. Reversing damage to critical sea grasses and marine life from rising water temperatures and pollution can reduce the greenhouse gas emissions driving climate change. For now this problem continues to accelerate and pose a significant threat to the communities around the Chesapeake Bay.