Seboomook Lake

About Seboomook Lake

The primary purpose of Seboomook Lake is hydroelectric. The dam generates hydroelectric power by channeling water through turbines, converting the energy of flowing water into electricity. It impounds the West Branch Penobscot River near Seboomook.

The dam stands 60 feet tall and stretches 607 feet across, creates a reservoir covering 6,838 acres, has a maximum storage capacity of 117,080 acre-feet, and collects water from a drainage area of 526 square miles. Completed in 1936, the structure is well-established, with more than 75 years of service.

This dam carries a high hazard potential classification, which means that a failure or uncontrolled release of water would likely cause loss of human life. This classification reflects the consequences of failure, not the likelihood — it indicates that people live or work in the area downstream. Its condition is rated satisfactory, indicating no existing or potential dam safety deficiencies are recognized. An emergency action plan is in place for this dam. The most recent inspection on record was 07/20/2022.

At 60 feet, this dam is taller than 95% of all dams in the United States.

Living Downstream

If you live or work downstream of this dam, consider taking these steps: learn your local evacuation routes, check whether your county emergency management office has a dam failure inundation map, and sign up for local emergency alerts. The Maine dam safety program can provide more specific information about emergency planning for this structure.

Search for dams near your address to see all dams in your area with hazard classifications and safety data.