LIHI Certificate #140 – Little Falls Project, Maine

The Little Falls Project is located on the Presumpscot River in Cumberland County, Maine. Several mills have existed at the Little Falls site since the early 19th century. C.A. Brown and Company purchased the site in 1875 and constructed a wood board mill. Later, in the early 1900s, the Androscoggin Pulp and Paper mill purchased the property. Although Central Maine Power Company owned the power rights in the 1950s, they did not operate it. Mr. Lawrence Keddy purchased the site in the 1960s and used the power in his nearby steel mill. S.D. Warren purchased the site in 1974 (later renamed Sappi North America, Inc.). There are six hydroelectric facilities on the Presumpscot River between Sebago Lake and the Atlantic Ocean in Portland, Maine. The Little Falls project is the fifth hydro project downstream of the Sebago Lake outlet. Upstream of the project are the Eel Weir (LIHI #137), North Gorham (LIHI #129), Dundee (LIHI #138), and Gambo (LIHI #139) Projects. The downstream project is Mallison Falls (LIHI #141).

The project includes the dam, intake structure, powerhouse, four turbines, bypass reach, and upstream eel passage. The dam is a 331-foot-long, 14- foot-high, reinforced concrete and masonry structure incorporating a 160-foot-long spillway section, a 101.5-foot-long spillway and sluice gate section, and a 70.5-foot-long intake structure. A masonry powerhouse is also integral to the dam. It contains four vertical Francis turbines direct-connected to generators with a total installed capacity of 1 MW. The bypass reach is 300 feet long, running between the dam and the powerhouse tailwaters.

The project operates in run-of-river mode and impounds a 29-acre reservoir. The project provides a minimum flow of 26 cfs into the bypass reach. The flow regime was developed based on studies conducted by Maine Department of Environmental Protection (MDEP) to ensure suitable riverine habitat is maintained for fish and wildlife resources.

Project Name Little Falls
LIHI Certificate No. 140
LIHI Certificate Term September 5, 2017 - September 4, 2022
Owner Sappi North America, Inc.
State Maine
Location Windham and Gorham, Cumberland Counties River mile 16.9 Presumpscot River
Installed Capacity 1.0 MW
Average Annual Generation 4,200 MWH
Facility Type run-of-river
FERC No. P-2941 issued 2003, expires 2053

Waters within the project reach are designated Class B. This area of the Presumpscot River has historically been impaired for low dissolved oxygen levels. Monitoring conducted by MDEP confirms that increased minimum flows at the project have achieved full attainment of dissolved oxygen standards in the downstream section of the river.

Downstream dams prevent anadromous fish passage at the project. Agencies retain the right to prescribe passage facilities should biological triggers be met that initiate passage construction. American eel passage facilities were installed in 2007 and have been updated to provide more effective access for eel passage. From September 1 through October 31, the project shuts down operations for 8 hours starting at sunset. This facilitates downstream migration of American eel. Shutdowns are coordinated with Maine Department of Marine Resources and USFWS to determine the most effective timing. Flows pass over the spillway and ensure safe migration into the bypass reach.

The project property consists of 2 acres not including the reservoir. The project’s operation and flow monitoring plan includes provisions for mitigating erosion through impoundment dewatering and re-fill procedures.

Threatened and endangered species potentially within project vicinity include: Northern Long-eared bat, Eastern Small-footed Bat, Little Brown Bat, Brook Floater, Least Bittern, Upland Sandpiper, Eastern Box Turtle, Spotted Turtle. Activities with the potential to affect the listed species include: removal of large trees that may provide roosting habitat for the bats; exposure/dewatering of the Brook Floater mussel during significant, prolonged impoundment drawdowns, loss of or fragmentation of habitat due to development for the Least Bittern, Upland Sandpiper, and Spotted Turtle, direct taking of Box Turtles for pets. The project owner expressed that none of these activities are planned at the project.

Cultural resources in the project vicinity include the Cumberland and Oxford Canal, the Oriental Powder Mill Complex, and an archaeological site. The project owner submits annual reports to the State Historic Preservation Office and the Penobscot Indian Nation detailing activities conducted under the project’s historic properties management plan.

Recreational resources at the project include a canoe portage trail and a carry-in boat launch.


Certification History

March 5, 2018 – The 30-day appeal window closed for the preliminary certification decision of the Little Falls Hydroelectric Project closed on March 1, 2018 with no appeals to the decision received. The decision is therefore final and Little Falls is LIHI Certificate #140. The Certification term will be September 5, 2017 – September 4, 2022. The certificate includes the following condition:

  • Condition 1. The Owner shall update LIHI on the following activities in the annual LIHI compliance statement:
    1. The status of the effectiveness testing of downstream passage of eels.
    2. The status of upstream and downstream anadromous fish passage activities at the Project and at the Saccarappa Project. The updates should include summaries of agency and stakeholder consultation and recommendations made, any changes in the fish passage plans from those described in the LIHI application, and any changes in passage requirements or the timing of implementation at both Projects. LIHI reserves the right to suspend its certification if the agencies do not determine that safe passage at the Project is being provided and that such passage needs have not been waived.
    3. A summary of any consultation with MIF&W and/or USFWS related to state or federally listed species identified as possibly occurring at the site that could be impacted by construction activities or non-routine operations or maintenance activities. This would also include impoundment drawdowns that would expose a significant portion of the river bottom, among other non-routine activities. A summary of the relevant triggering activities and the measures implemented during the year to protect such species shall also be provided.
    4. The status of completion of the outstanding portage take-out/put-in or a viable alternative. A copy of FERC’s acceptance of the December 2017 request for extension of time, and FERC’s subsequent acceptance of the completed facility shall also be provided when it becomes available.

January 30, 2018 – On January 24, 2018, the Low Impact Hydropower Institute (LIHI) preliminarily approved Low Impact Certification for the Little Falls project. This decision is preliminary pending the 30-day appeal window. Only those who commented in the initial application 60-day comment period are eligible to file an appeal. Such appeal needs to include an explanation as to how the project does not meet the LIHI criteria. Appeal requests can be submitted to comments@lowimpacthydro.orgRequests must be received by 5:00 pm Eastern time March 1, 2018.

September 7, 2017 – On September 7, 2017, the Low Impact Hydropower Institute (LIHI) received a complete application from S.D. Warren Company d/b/a Sappi North America for the Low Impact Certification of the Little Falls Project, FERC No. P-2941.

LIHI is seeking comment on the Little Falls application for certification. Comments that are directly tied to specific LIHI criteria (flows, water quality, fish passage, etc.) will be most helpful, but all comments will be considered.  Comments may be submitted to the Institute by e-mail at comments@lowimpacthydro.org with “Little Falls Project Comments” in the subject line, or by mail addressed to the Low Impact Hydropower Institute, 329 Massachusetts Avenue, Suite 2, Lexington, MA 02420.  Comments must be received at the Institute on or before 5 pm Eastern time on November 7, 2017 to be considered.  All comments will be posted to the web site and the applicant will have an opportunity to respond.  Any response will also be posted.