The Cathance River is a 16.4 miles (26.4 km) river in Maine

Maine

Maine is a state in the New England region of the northeastern United States, bordered by the Atlantic Ocean to the east and south, New Hampshire to the west, and the Canadian provinces of Quebec to the northwest and New Brunswick to the northeast. Maine is both the northernmost and easternmost...

 flowing into Merrymeeting Bay

Merrymeeting Bay

Merrymeeting Bay is a large freshwater tidal bay in Sagadahoc, Lincoln, and Cumberland counties, in the U.S. state of Maine. Merrymeeting Bay's unusual geography defies common landform terms. It is not what is usually meant by the word bay. It is somewhat like an estuary except for being fresh...

.

It rises in Bowdoin

Bowdoin, Maine

Bowdoin is a town in Sagadahoc County, Maine, United States. The population was 2,727 at the 2000 census. It is part of the Portland–South Portland–Biddeford, Maine metropolitan statistical area.-History:...

 at the junction of West Cathance and East Cathance streams and flows south into Topsham. Turning east and then northeast, it reaches tidewater at the village of Cathance within Topsham and continues northeast into the town of Bowdoinham

Bowdoinham, Maine

Bowdoinham is a town in Sagadahoc County, Maine, United States. The population was 2,612 at the 2000 census. It is part of the Portland–South Portland–Biddeford, Maine metropolitan statistical area. The town is located on the west side of Merrymeeting Bay.-History:Fort Richmond was...

. The river turns south again for its final course to Merrymeeting Bay.