Wassaw Island is one of the Sea Islands. It is located on the Atlantic Ocean off the coast of the U.S. state of Georgia and is within the borders of Chatham County. The island and its surrounding marshlands are part of the Wassaw National Wildlife Refuge, which has a total area of 10,053 acres of marsh, mudflats, and tidal creeks, including approximately 7 …Wassaw Island is one of the Sea Islands. It is located on the Atlantic Ocean off the coast of the U.S. state of Georgia and is within the borders of Chatham County. The island and its surrounding marshlands are part of the Wassaw National Wildlife Refuge, which has a total area of 10,053 acres of marsh, mudflats, and tidal creeks, including approximately 7 miles of undeveloped beaches. The land mass is 76 percent salt marshes and 24 percent beaches, dunes, and maritime forest. The refuge is a part of the Savannah Coastal Refuges Complex.