LIHI Certificate #65 - Medway Project, Maine

The Medway Hydroelectric Project is a run-of-river hydroelectric generating facility located on the West Branch of the Penobscot River in Medway, Maine with a gross nameplate generating capacity of 3.44 MW. The Medway Project commenced initial commercial operations in 1923. The Medway Project generates clean, renewable electricity while providing recreational opportunities (portage trail and boat launch), fish passage measures, consistent water levels that enhance habitats for waterfowl, etc., and substantial support of the local community through stable property tax payments, reliable voltage support of the electrical distribution system, etc.
The Medway Project consists of a 343-foot-long concrete gravity dam surmounted by flashboards, a 64-foot-long concrete gravity forebay wall, a 120-acre impoundment, a powerhouse containing five generating units with a total installed capacity of 3.44 MW, an approximate 144-foot-long underground transmission line, and appurtenant facilities. The Medway hydroelectric project is a component of the Penobscot River Restoration Agreement. The overall intent of the Agreement is to provide enhancements to the Penobscot River's environmental resources, and lower and minimize the influence of the Owner's hydroelectric projects on those resources while maintaining the levels of renewable hydropower generation from the river. The restoration effort is one of the largest river restoration projects in our nation's history. In an unprecedented collaboration, a diverse group of stakeholders are working together to restore 11 species of sea-run fish to the Penobscot River, while maintaining energy production. On June 25, 2004, the Lower Penobscot River Basin Comprehensive Settlement Accord (“Lower Penobscot Agreement”) was signed. The Agreement represented an unprecedented collaboration to restore 11 species of sea-run fish while rebalancing hydropower generated on the river. An integral part of the energy balance associated with the Agreement included amending the license for the Medway Hydroelectric Project. In June 2004 an application was filed with the Federal Energy Regulatory Commission (“FERC”) for the amendment and FERC issued the amendment on April 18, 2005. Pursuant to the Lower Penobscot Agreement, BBHP plans to add an additional 700 KW generating unit to the existing Medway Project Powerhouse. The Medway Project license was transferred to Black Bear Hydro Partners, LLC by FERC order dated September 17, 2009.
Project Name Medway
LIHI Certificate No. 65
LIHI Certificate Term June 1, 2020 - May 31, 2025
Owner Black Bear Hydro Partners LLC
State Maine
Location Located at river mile 0.7 on the West Branch of the Penobscot River in Medway, Maine.
Installed Capacity 3.44 MW
Average Annual Generation 29,944 MWh
Facility Type Run-of-river
FERC No. P-2666 issued 1999, expires 2029

Certification History

April 26, 2021: The decision to recertify the Medway Project became final after the close of the appeals period on April 17, 2021 with no valid appeals filed. The Certification term is from June 1, 2020 through May 31, 2025. The certification includes the following conditions:

  • Condition 1: The facility Owner shall provide LIHI a copy of agency correspondence documenting numerical performance standards that the agencies may establish for upstream and/or downstream passage for the Penobscot River basin that affect the Medway Project, within 60 days of publication of the standards.
  • Condition 2: In annual compliance statements, the facility Owner shall summarize any new agency or PIN requests for upstream eel passage studies or modifications to the eelway, and/or for provision of upstream passage for anadromous species. Documentation shall include the agency requests and any plans and schedule for implementing the requested activity(ies). Annual updates shall document agency communications, discussion of resolution of disagreements should they occur, and project modifications made or results of studies during the prior year. LIHI reserves the right to modify this condition in light of future Project changes.
  • Condition 3: The facility Owner shall provide LIHI a copy of the 2021 downstream eel passage study results, agency and PIN comments, and plans and schedules for any agreed upon modifications needed as a result of the study. Should the Owner not agree to make all requested modifications, the rationale for these decisions shall be provided. LIHI reserves the right to modify this condition based on the study results and assessment of the effectiveness of downstream passage.

March 18, 2021: The Low Impact Hydropower Institute (LIHI) has preliminarily approved recertification of the Medway Project for a new 5-year terms of Low Impact Certification.

This decision is preliminary pending the 30-day appeal window. Only those who commented on the initial application during the 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 by email to with "Medway Project” in the subject line, or by mail addressed to the Low Impact Hydropower Institute, 1167 Massachusetts Ave, Arlington MA 02476. All requests will be posted to the website. The applicant will have an opportunity to respond and any response will also be posted. Requests must be received by 5 pm Eastern time on April 17, 2021. The full application and reviewer's report is available below.

If no appeal requests are received and the decision becomes final, the Certification term for the Project will be June 1, 2020 through May 31, 2025.

December 1, 2020: The Low Impact Hydropower Institute has received a complete application for Low Impact recertification of the Medway Project. The complete application can be found below.

LIHI is seeking public comment on these applications. 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 “Medway Project Comments” in the subject line, or by mail addressed to the Low Impact Hydropower Institute, 1167 Massachusetts Avenue, Arlington MA 02476. Comments must be received on or before 5 pm Eastern time on January 30, 2021 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.

August 5, 2016: LIHI Executive Director Michael J. Sale, using authority delegated from the LIHI Governing Board, has issued a Preliminary Certification Decision that the Medway Hydroelectric Project (FERC No. P-2666) satisfies the LIHI Certification Criteria.  This Preliminary Certification Decision includes one facility-specific condition, as follows:

  • Condition 1.  The Owner shall be proactive in contacting the MIFWS a minimum of 30 days prior to any planned drawdown of the impoundment that would expose a significant portion of the river bottom, to determine if any special measures are needed to avoid or minimize adverse impacts to state-threatened mussels that may be in the impoundment. The Owner shall work with the MIFWS to implement appropriate mitigation measures should they be needed.  The Owner shall advise LIHI of any such events, including the results of any activities conducted to minimize such impacts. Such notification shall be provided as part of the annual compliance statement to LIHI.

As provided for in Section 4.2.5 of the LIHI 2nd Edition, the Preliminary Certification Decision to certify, along with the Application Reviewer’s report and (if prepared) report of the Executive Director, will be posted on the Institute’s Web page for 30 days.  Notice of the posting will be provided to all individuals or organizations that commented on the initial Application Package.Any Commenter may submit a letter to the Executive Director requesting an appeal within the 30-day period.  The appeal request must state specific reasons why the hydropower facility should have failed one or more criteria.  If an individual or organization did not comment on the initial Application Package, they may not file an appeal.  Further information about the LIHI appeal process is available in the LIHI Handbook, available at

If no appeal is requested within the 30-day period, the Executive Director will issue LIHI Certification for the facility and post a notification of certification on the Institute’s website.  Once final, the effective certification date for the Medway Project is June 1, 2015 for a five (5) year term, which will expire on June 1, 2020.

December 11, 2015: The Low Impact Hydropower Institute has received a complete application for a new term of Low Impact Certification for the Medway Hydroelectric project.  The application materials can be found in the Files section below.

The public comment period for this application closed on February 12, 2016.

January 28, 2011: The Medway Hydroelectric Project has been certified as low impact for a five year term, effective June 1, 2010 and expiring June 1, 2015.

August 2, 2010: Public comment period for the application for certification has been closed.

June 2, 2010: Black Bear Hydro Partners has submitted an application for certification of the Medway Hydroelectric Project. The public comment period on the application will remain open for 60 days.