Project Description

The Gambo Project was originally constructed in 1911 and is the fourth hydro project downstream of the Sebago Lake outlet. The Project was originally FERC licensed in 1980, and currently holds a 40‐year license issued on October 2, 2003.  It has a 24-foot-high dam, a 737-foot-long, 15-foot-deep intake canal, and 2 Francis turbines. It is a run-of-river facility equipped with upstream passage for American eel.

Project Name Gambo
Owner S.D. Warren d/b/a Sappi North America
LIHI Certificate 139
LIHI Effective and Expiration Dates September 5, 2017 – September 4, 2022
State Maine
Location Windham and Gorham, Cumberland County

River mile 18.6 on the Presumpscot River

Installed Capacity 1.9 MW
Average Annual Generation 7,000 MWh
Facility Type run-of-river
FERC No. 2931

Certification History

March 23, 2018: The appeal period for the Preliminary Decision to certify the Gambo hydroelectric project has closed with no requests to appeal. The decision is therefore final. Island Park is LIHI Certificate #138.

January 30, 2018: On January 24, 2018, the Low Impact Hydropower Institute (LIHI) preliminarily approved Low Impact Certification for the Gambo project with the following conditions:

Condition 1. The Owner shall notify LIHI when the modifications to the Project to improve upstream eel passage are completed and submit copies of MDMR and USFWS comments related to whether these modifications are sufficient, and/or if additional effectiveness testing is required to confirm that eels are safely passing upstream at the Project.  If additional testing is required, the schedule and final results along with agency comments on the report, agency recommendations for modifications, and plans and schedule for any needed modifications to shall also be provided to LIHI.

Condition 2.  The Owner shall update LIHI on the following activities in the annual LIHI compliance statement:

  1. The status of Condition 1 above.
  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.

The reviewer’s report is attached at the bottom of this page. 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 Requests 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 Gambo Hydroelectric Project, FERC No. P-2931, located on the Presumpscot River in Maine.

LIHI is seeking comment on the Gambo 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 with “Gambo 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.