FIND YOUR
region within the WATERSHED
Casco Bay is an estuary – a place where rivers meet the sea. Casco Bay was named an “estuary of national significance” (a designation under the Clean Water Act) in 1990 because of its richness and diversity of marine life. The Casco Bay Watershed is the land area from which water flows into rivers and streams and ultimately, into Casco Bay.
Casco Bay supports 850 species of marine life, and contains about 8,200 acres of eelgrass beds. This nationally significant embayment is home to important commercial species such as clams, lobsters, and numerous fish species. The waters and islands of Casco Bay cover nearly 200 square miles from Cape Elizabeth to Cape Small in Phippsburg. From the top of the watershed, in the western mountains near Bethel, to the coast, all the waters that flow to the sea are part of the Casco Bay Watershed. The six regions are based on municipal boundaries. The regional descriptions contain maps and information on organizations serving that area.
Twelve significant lake and river systems feed the Bay, including Sebago Lake and three major freshwater tributaries: the Presumpscot, Royal and Stroudwater Rivers. Casco Bay is dotted with roughly 785 islands, islets, and exposed ledges.
Towns in the Casco Bay
watershed have been divided into six regions that cluster around major subwatersheds:
Eastern Bay
New Meadows; Harpswell Sound/Quahog; Maquoit & Middle Bays
Inner Bay
Harraseeket River; Broad Cove/Cumberland & Falmouth Foresides; Islands
Presumpscot
Lower Presumpscot
Royal
Royal & Cousins Rivers
South Bay
Fore River & Back Cove; Southern Bay
Upper Watershed
Sebago/Upper Presumpscot
Regional Groups in Casco Bay
Many regional and state-wide groups include Casco Bay in their planning, management, habitat protection, monitoring, and outreach efforts. A listing, including contact information, for many of these organizations is available here.
The photo illustrates a pilot project undertaken by the Eelgrass Consortium, made up of MeDEP, USGS, FOCB, USFWS, and CBEP, to test methods of transplanting eelgrass in Casco Bay.