Southeastern Massachusetts, SEMA, is the region south of Boston, West of Cape Cod Bay, East of Providence and North of Buzzards Bay. Historically the region was largely defined as the tribal lands of the Wampanoag Native American nation. SEMA includes 500 miles of major rivers and streams that have long been a core part of the culture in each community, offering historically important venues for commerce, fisheries (both inland and coastal), hydro power for grist mills, and boatbuilding trades. Today, Southeastern Massachusetts has multiple watersheds (boundaries in black in map) that are complex networks of wetlands, streams, and rivers and sometimes tidelands that are home to many critical environmental resources, including globally rare species, coastal plain ponds, pine barrens, free-flowing undammed rivers, the states’s second largest underground aquifer, and the largest freshwater swamp in Southern New England (Hockomock Swamp). Groundwater resources include the Canoe River aquifer and the Plymouth-Carver aquifer. The ground water/surface water interactions are critical to sustaining the aquatic habitats of our watersheds.