Flagstaff Submerged To Form Flagstaff Lake
Latitude / Longitude:
45°11′38.9″N 70°18′52.4″W / 45.194139°N 70.314556°W / 45.194139
1,146 feet (349 m)
Eastern (EST) (UTC-5)
Flagstaff Lake is located in Somerset County and Franklin County, Maine in the United States. The North Branch Dead River and South Branch Dead River join in the lake, forming the Dead River.
The lake’s surface area is 20,300 acres (82 km2), and it has a storage capacity of about 275,482 acre-feet. It is extremely shallow (more so during drought years). Its deepest point is 48 feet (15 m). Landlocked salmon and brook trout can be caught. Some points on the lake are very marshy and have to be negotiated with a canoe or kayak; even then, wading may be necessary in the marshy areas to get through to the rest of the lake.
Flagstaff Lake was a smaller natural lake when the Long Falls Dam impounded the Dead River in 1950, enlarging the lake and turning it into a reservoir used for hydropower electricity production by regulating the flow of the Dead River into the Kennebec River. At the time, the river drive was still a primary means of delivering timber to the pulp mills downstream. Improved highways and the trucking industry have replaced the river drive.
The dam is 45 feet high, 1339 feet long at its crest, and consists of a 450-foot concrete spillway, a 125-foot-long concrete section containing five 20-foot-wide Tainter gates, a 70-foot-long concrete section containing two Broome gates, a fishway, and a log sluice, and a 694-foot-long earthen dike. The dam is owned and operated by NextEra Energy, but no electricity is generated here. The dam is operated to regulate and augment flows that are used by eight downstream mainstem Kennebec River hydropower projects, and to control flooding.