Information Sheet
Hydropower Relicensing

Revised: March 2014         Contact: (207) 287-7688

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The relicensing of hydroelectric generating and water storage dams in Maine provides a once-in-a- lifetime opportunity to shape the destiny of our river resources.

Hydropower Licensing

Hydropower projects are licensed by the Federal Energy Regulatory Commission (FERC) which has jurisdiction over all generating and storage dams on navigable waters. Projects on non-navigable rivers that have undergone post-1935 construction and affect interstate commerce (as through an inter- connection with a public utility power grid) also fall under FERC’s control. Licenses are valid for 30 to 50 years and must then be renewed.

102 hydropower dams are now licensed in Maine. These have a combined installed generating capacity of over 743 megawatts (roughly equivalent to one nuclear power plant), as well as billions of cubic feet of water storage capacity. An additional 27 small-scale hydro projects have an exemption from licensing.

Relicensing Activity in Maine

Since 1979, 55 Maine hydropower dams have been relicensed. Another 11 dams are currently pending for relicensing, with more dams due for relicensing in coming years. And one dam—the Edwards Dam in Augusta—has been removed after relicensing was denied by FERC. See the reverse side of this sheet for a table of license expirations in Maine.

The State’s Role in Relicensing

In order for a hydropower project to be relicensed by FERC, the State must first certify that continued operation of the project will comply with Maine’s water quality standards. These standards relate to the waterbody’s physical characteristics (e.g., minimum dissolved oxygen levels) as well as its designated uses (recreation, fishing, aquatic habitat, etc.). Existing in-stream uses must be protected under the State’s “antidegradation” policy.

By Executive Order of the Governor, DEP is the certifying agency for all hydropower project licensing and relicensings statewide, except for projects in unorganized territories subject to permitting by the Land Use Regulation Commission.

Through the water quality certification process, the DEP has imposed various conditions on projects undergoing relicensing to ensure that State water quality standards are maintained. Typical conditions include minimum flow releases, allowable
impoundment drawdowns, construction of public boat ramps, canoe portage trails, and other recreational facilities, and construction of new or improved fish passage facilities.

The DEP can regulate in another way as well. Any proposed relicensing that calls for the expansion of an existing dam or generating facility must be approved under the Maine Waterway Development and Conservation Act. This statute requires an evaluation of the full range of potential impacts, including impacts on wetlands, water quality, soils, fish and wildlife resources, historic and archaeological sites, public access, flooding, and energy generation.

Federal Role in Relicensing

To issue a license under the Federal Power Act, originally enacted in 1920, FERC must find that a project is “best adapted to a comprehensive plan for improving or developing a waterway.” The Electric Consumers Protection Act of 1986 directs FERC to consider power and non-power uses in making this determination. Specifically, FERC must give “equal consideration to the purposes of energy conservation, the protection, mitigation of damage to, and enhancement of fish and wildlife, the protection of recreational opportunities, and the preservation of other aspects of environmental quality.”

The Relicensing Process

Relicensing begins with a 3-to-5 year pre- application consultation process during which applicants, agencies and other interested parties identify environmental issues, address information needs, and explore mitigation options. Any necessary studies are then conducted, and a draft application is prepared for review and comment.

Federal law requires that a final application for relicensing be filed with FERC no later than 2 years prior to license expiration. If necessary, FERC will issue annual extensions of the license until the relicensing process is complete.


Hydropower relicensing will greatly affect the character of the State’s river resources for the next generation. DEP is committed to working with other agencies and the public to achieve a carefully considered balance among competing uses and resources, a balance that will enhance environmental values while encouraging the wise multiple use of Maine’s rivers.

license expiration project/dam river
2000 Forest City* St. Croix
West Grand Lake* St. Croix
Sysladobsis Lake* St. Croix
Howland* Piscataquis
2004 Eel Weir* Presumpscot
2012 Brassua Moose
2016 Vanceboro St. Croix
2017 Williams Kennebec
West Buxton Saco
2018 Mattaceunk Penobscot
Ellsworth Union
Graham L. Union
2019 Lower Barker L. Androscoggin
American Tissue Cobboseecontee
2020 CMP Dam Goose
Mill Dam Goose
Kelly Dam Goose
Mason Dam Goose
Swan L. Goose
2021 Shawmut Kennebec
Squa Pan Squa Pan
Rollinsford Salmon Falls
Somersworth Salmon Falls
2022 Hiram Saco
Great Falls Salmon Falls
Pejepscot Androscoggin
Kesselen Dam Mousam
Twine Mill Dam Mousam
Dane Perkins Mousam
2023 Errol Androscoggin
Upper Barker L. Androscoggin
Pumpkin Hill Passadumkeag
2024 West Enfield Penobscot
Upper Rumford Falls Androscoggin
Lower Rumford Falls Androscoggin
Hackett Mills L. Androscoggin
Green Lake Union
2025 Worumbo Androscoggin
Aziscohos Magalloway
2026 Lewiston Falls Androscoggin
North Twin Penobscot
Millinocket Penobscot
Dolby Penobscot
East Millinocket Penobscot
Millinocket Lake Penobscot
Ripogenus Penobscot
Upper Andro Androscoggin
Eustis Dead
2029 Brunswick Androscoggin
Medway Penobscot
Cataract Saco
Springs/Bradbury Saco
license expiration project/dam river
2030 Upper Kezar Falls Ossipee
Lower Kezar Falls Ossipee
2033 Damariscotta Damariscotta
2034 North Gorham Presumpscot
Benton Falls Sebasticook
2036 Messalonskee Lake Messalonskee
Oakland (M2) Messalonskee
Rice Rips (M3) Messalonskee
Automatic (M4) Messalonskee
Union Gas (M5) Messalonskee
Hydro-Kennebec Kennebec
Weston Kennebec
Wyman Kennebec
Flagstaff Lake** Dead
Harris Kennebec
Moosehead Lake Kennebec
Sandy River Sandy River
Burnham Sebasticook
Lockwood Kennebec
2036 Gulf Island-Deer Rips Androscoggin
2037 South Berwick Salmon Falls
Marcal L. Androscoggin
2038 Skelton Saco
Bonny Eagle Saco
Milford Penobscot
Stillwater Stillwater
2043 Saccarappa Presumpscot
Gambo Presumpscot
Mallison Falls Presumpscot
Little Falls Presumpscot
Dundee Presumpscot
2044 Millinocket Lake Aroostook
Caribou Aroostook
2045 Orono Stillwater
2048 Riley Androscoggin
Jay Androscoggin
Livermore Falls Androscoggin
Otis Androscoggin
Bar Mills Saco
2052 Mooselook-meguntic Lake Rapid
Richardson Lakes Rapid
2054 Anson Kennebec
Abenaki Kennebec
Canada Falls Lake Penobscot
Seboomook Lake Penobscot
Ragged Lake Penobscot
Caucomgomoc Lake Penobscot

* Currently operating under annual license.
** New license currently stayed.