LIHI Certificate #57 - Oakdale Project, Massachusetts

The MWRA supplies wholesale water to local water departments in 50 communities, primarily in the Boston metropolitan area. On average, MWRA supplies approximately 200 million gallons per day to its water system customers. MWRA's water comes from the Quabbin Reservoir, about 65 miles west of Boston, and the Wachusett Reservoir, about 35 miles west of Boston. Both Quabbin and Wachusett Reservoirs are man-made reservoirs, constructed for water supply purposes. More than 50% of the inflow into the Wachusett Reservoir is transferred from Quabbin Reservoir via the Quabbin Aqueduct/Tunnel.   From Wachusett Reservoir, the Cosgrove Aqueduct conveys water to the John J. Carroll Treatment Plant (JJCWTP) in Marlborough.  After treatment, water is sent eastward via the MetroWest Tunnel or Hultman Aqueduct (back-up).

Downstream of JJCWTP and close to its centers of demand, MWRA has recently constructed a new network of tanks to protect and store treated drinking water in compliance with the Federal Safe Drinking Water Act.  The network of new tanks includes the Norumbega and Loring Road Covered Storage Facilities.  From the tanks, water is then distributed to member communities.

The 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 at the end of the Quabbin Aqueduct; the Cosgrove Intake to the Cosgrove Aqueduct, and at the Loring Road Covered Storage Facility (this facility is under construction and will become operational in fall, 2010).

The Oakdale hydroelectric facility is located at the outlet of the Quabbin Aqueduct just upstream of Wachusett Reservoir and near the mouth of the Quinepoxet River.  Quabbin Aqueduct is a deep rock tunnel.  The water enters the aqueduct at Quabbin Aqueduct Intake, Shaft 12 and travels over 24 miles to its terminus to the Oakdale transfer station in West Boylston Massachusetts.  It is one of the locations in the MWRA water transmission system where MWRA currently captures energy in falling water as it is conveyed from higher elevations in the western portion of the MWRA system (Quabbin Reservoir) to lower elevations in the distribution area. Generation of hydropower is secondary to MWRA’s primary objective of water supply, and is legally subordinate to MWRA’s obligation to provide high quality drinking water.

The Oakdale facility is operated and maintained by MWRA.  The Oakdale station was constructed in 1929 as an outlet works of Quabbin Tunnel, and was initially operated solely as a water transfer station. In 1949, a hydropower generator was added.

The project generated approximately 9,000 mWH in 2009. The hydropower generated is sold to West Boylston Municipal Lighting Plant. Revenues from the sale of power to West Boylston are used to offset the costs of operating the Massachusetts Department of Conservation and Recreation’s (DCR) Watershed Protection Division.  DCR and MWRA are partners in watershed protection and MWRA rate payers fund the DCR Watershed Protection Division.

Project Name Oakdale
LIHI Certificate No. 57
LIHI Certificate Term April 14, 2015 - April 14, 2023
Owner Massachusetts Water Resource Authority
State Massachusetts
Location Located at the outlet of the Quabbin Aqueduct just upstream of Wachusett Reservoir and near the mouth of the Quinepoxet River.
Installed Capacity 3.5 MW
Average Annual Generation 10,000 – 13,000 MWH
Facility Type conduit
FERC No. P-10689 exempt 1990

Certification History

December 7, 2015: LIHI Executive Director Michael J. Sale, using authority delegated from the LIHI Governing Board, has issued a Preliminary Certification Decision that the Oakdale 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 Oakdale Project is April 14, 2015 for an eight (8) year term, which will expire on April 14, 2023.

October 22, 2015:  The Oakdale 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 Oakdale 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 Oakdale Hydroelectric project has been granted an extension of the current certificate term. The new expiration date is October 11, 2015.

July 21, 2010: The Oakdale 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 for the application for certification has been closed.

June 9, 2010: LIHI received the following comment letter from the USFWS regarding the Oakdale Project. It can be found in the Files section below.

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