LIHI Certificate #55 - Cosgrove Project, Massachusetts

Project Name Cosgrove
LIHI Certificate No. 55
LIHI Certificate Term April 14, 2023 – April 13, 2038
Owner Massachusetts Water Resource Authority
State Massachusetts
Location Located at the Cosgrove Intake in the Cosgrove Aqueduct
Installed Capacity 2.4 MW
Average Annual Generation 4,623 MWh
Facility Type conduit
FERC No. P-10688 exempt 1990

The Cosgrove Project is located at the Cosgrove Intake. The Cosgrove Intake and hydroelectric facility regulates the flow of water from the Wachusett Reservoir into the Cosgrove Aqueduct, which is an important transmission leg in the supply of water to the Boston Metropolitan area.

The Massachusetts Water Resources Authority (MWRA) transmission system consists of over 100 miles of tunnels and aqueducts that transports water largely by gravity to points of distribution within the MWRA service area. There are three locations within this water transmission system where hydroelectric facilities are located. These include Oakdale (LIHI #57) at the end of the Quabbin Aqueduct; the Cosgrove Intake to the Cosgrove Aqueduct; and the Loring Road Covered Storage Facility (LIHI #56).

The hydroelectric facility generates power from potable water as it is transferred from the Wachusett Reservoir into the MetroWest Tunnel for eventual distribution throughout MWRA’s Service territory. The project includes two sections, the North and South intakes, and both intakes include a hydraulic turbine and two bypass lines. Each intake has three channels with traveling water screens. Each intake also has an upper intake sluice gate and lower intake sluice gate that allow operational flexibility to draw water from different levels of the reservoir. On the North intake, after this sluice gate, the water enters a common wet-well and from the wet well, flow is directed to either the turbine generator 1, bypass line 1 or bypass line 2 or a combination. Each of the bypass lines contains a sleeve valve, which is designed to regulate flows to the water supply transmission system over a range of flows. The configuration of the South intake parallels the North intake and flows entering the South intake are directed to either turbine generator 2, or bypass line 3 or bypass line 4.

The turbines are vertically oriented, full Kaplan type with six adjustable runner blades. The turbine generators were put into operation in 1969 and were recently rehabilitated and upgraded, having a total installed capacity of 2.4 MW. These upgrades were necessary to integrate the turbine operation with a newly configured water supply system. Electricity is used on site as well as exported to the regional electrical grid generating income for MWRA.

The project operates as a conduit facility and is located on a water transfer aqueduct. Waters are transferred from one water supply reservoir to another and do not discharge into a river.

Waters within the project reach are treated and utilized for water supply purposes and are thus high quality and potable.

Fish passage is not necessary nor feasible due to the conduit nature of the project.

The facility is located in a water distribution facility and the Massachusetts Department of Conservation and Recreation (DCR)  Division of Water Supply is responsible for shoreline protection. MWRA maintains a partnership with the Massachusetts Department of Conservation and Recreation Division of Water Supply Protection, which is responsible for managing the activities within the watershed funded by MWRA.

There are no threatened or endangered species that could be affected by the project which is located inside a building.

No cultural or historic resources exist at the hydro project.

The project is located at a public water supply which restricts public access to project facilities.

Compliance Status

There are no facility-specific conditions in the current Certificate

2024: No material changes or compliance issues were identified. The project remains in compliance based on the annual review.

2023:  Annual reporting for the current Certificate has not yet taken effect.

Certification History

December 21, 2023: The Low Impact Hydropower Institute has issued a final decision on the recertification of the Cosgrove Hydroelectric Project  The certification term is April 14, 2023 through April 13, 2038.

November 17, 2023: The Low Impact Hydropower Institute has preliminarily approved Low Impact recertification for the Cosgrove Hydroelectric Project (LIHI #55) located on the Cosgrove Aqueduct in Massachusetts. The full application and reviewer’s report are available below. 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 “Cosgrove 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 December 17, 2023. If no appeal requests are received the certification term will be April 14, 2023 through April 13, 2038.

September 5, 2023: The Low Impact Hydropower Institute (LIHI) has received a complete recertification application from Massachusetts Water Resource Authority for the Cosgrove Project.  LIHI is seeking comment on this application. 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 LIHI by e-mail at with “Cosgrove 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 at the Institute on or before 5 pm Eastern time on November 6, 2023 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. The project complete application can be found below.

January 13, 2016: LIHI Executive Director Michael J. Sale, using authority delegated from the LIHI Governing Board, has certified that the Cosgrove Hydroelectric Project (FERC No. P-10689) continues to satisfy the LIHI Certification Criteria. A Preliminary Decision was announced on December 14, 2015, and a 30-day appeal period was open through January 14, 2016. No requests for appeal were received. The effective certification date for the Cosgrove Project is April 14, 2015 for an eight (8) year term, which will expire on April 14, 2023.

October 22, 2015:  The Cosgrove Hydroelectric Project has been granted an additional extension; the new expiration date is December 31, 2015.

September 30, 2015 – The Low Impact Hydropower Institute received a complete application for a new term of Low Impact Certification for the Cosgrove Hydroelectric project on September 21, 2015.  The application materials can be found in the Files section below.

The public comment period for this application closed on November 30, 2015.

June 19, 2015: The Cosgrove Hydroelectric project has been granted an extension of the current certificate term. The new expiration date is December 31, 2015. See ExtensionLetter_2015Recert for explanation below.

July 21, 2010: The Cosgrove Hydroelectric Project has been certified as low impact for a five year term, effective April 14, 2010 and expiring April 14, 2015.

June 14, 2010: The public comment period on the application for certification has been closed.

June 9, 2010: LIHI received a comment letter from the USFWS regarding the Cosgrove Project. It can be read in the Files section below.

April 14, 2010: The Massachusetts Resource Water Authority has submitted an application for certification of the Cosgrove Hydro Project. A public comment period will remain open for 60 days.

Certification Files

2023 Recertification

2015 Recertification

2010 Certification

Key Documents