The Cathance River flows southeastwardly to Merrymeeting Bay in Bowdoinham, about five miles north of Bath. Navigational activity in Merrymeeting Bay, where the Androscoggin and Cathance rivers join the Kennebec River, is limited to transient recreational craft.
The project involved constructing a 2.1-mile-long channel, 10 feet deep and 200 feet wide, through Merrymeeting Bay. The channel extends eastward from the mouth of the Cathance River, through the bay, to a point near the confluence of the Cathance and Kennebec rivers known as "The Chops." The work was completed in 1883.