3 Millimeters

Blackwater got its name from the tea-colored local rivers, dyed from tannin as water filters through peat soil in the marshes. In the Early Spring, trappers catch muskrats who build their huts on the marsh. The department of forestry also performs controlled burns every year to allow new grow to reach the sun quicker, fortifying the soil and protecting against stronger erosion due to sea level rise. Each year, more of the marsh disappears, replaced with open water which lines the roads through the preserve.

Many of the homes near Blackwater National Wildlife Refuge are either abandoned or for sale. As marshland encroaches on property, longtime residents have few options. Fewer families, if any, are moving in. "I doubt there'll be any human life here in 100 years." Donald Webster, who lives near Blackwater NWR and works for the Maryland Department of Natural Resources, said. Rising sea level is the shortest of tidal waves, but has the longest effects on the people and land it consumes.

Crisfield, built on a bed of millions of oyster shells, is a small fishing town at the southern end of Maryland. Tradition thrives in the summer with seafood festivals and boat docking races; families build vacation homes near the water so they can watch herons, egrets and other waterfowl take flight over the marshes during sunset. Every winter, watermen dredge frigid waters to dig out a living harvesting oysters.

During this century, sea level is expected to rise about three times as much as in the 20th century on Maryland's shores. With that projection, much of Crisfield would be submerged. "Crisfield was the seafood capital of the world," resident Billie Chandler said. "What are they going to do 50 years from now? Say, 'Underneath that water used to be the seafood capital of the world'?"

There is nothing to stop Smith Island from slowly drowning. As one of the last occupied islands in the Chesapeake Bay, its plight is clear: The small water-locked piece of land, accessible only by boat, has a dwindling population of 264 townspeople and a declining height of four feet above sea level. The Maryland Department of Natural Resources predicts that Smith Island has, at most, 50 years before it is solely marshland, and 100 years before it is gone.

North of Smith Island, the road leading to the bridge connecting Hoopersville to the mainland has the churning bay on both sides, often needing only a high tide to crest the roadway. It's the only road in or out of the community and can leave residents stranded during weather events. "You can raise the houses but you can't raise the roads and you can't raise the driveways," Tom Horton, a Chesapeake historian, said.

Talbot county, one of the oldest centers of European settlements in America, has more than 600 miles of tidal shoreline, the most of any county in the United States. The county is home to Unionville, a historic African-American community settled by ex-slaves and free blacks.

Leading up to the Civil War, Maryland's border-state identity led to strong divisions in the community. There is still a contentious battle over a statue on the courthouse lawn commemorating the Talbot County residents who fought for the confederacy.