LIHI Certificate #89 - Holyoke Project, Massachusetts

Project Name Holyoke
LIHI Certificate No. 89
LIHI Certificate Term
January 1, 2017 – January 1, 2030 (option to extend to January 1, 2032)
Owner City of Holyoke Gas & Electric Department
State Massachusetts
Location Located at river mile 87 in Holyoke and South Hadley, Massachusetts, 12.6 miles north of the Connecticut State Line.
Installed Capacity See table below
Average Annual Generation See table below
Facility Type Run-of-river, conduit
FERC No. See table below

The Holyoke Project is located on the Connecticut River in Holyoke and South Hadley, Massachusetts. The dam and canal system were conceived and constructed as one system by the South Hadley Falls Company starting in 1847-1848. The purpose of the system was to harness the power of Hadley Falls by diverting water from the Connecticut River to mills for mechanical power for manufacturing. The first hydroelectric turbine was installed within the canal system in 1888. Holyoke dam continued to be used solely for diversion of flow until 1950 when the first hydroelectric turbine was installed; a second unit followed in 1983. The project consists of 11 operating developments: Hadley Falls, Boatlock Station, Skinner Station, Chemical, Riverside #4-8, Holyoke 1-4, and Valley Hydro (Station #5). The Holyoke Canal system consists of three levels, referred to as First, Second, and Third Level Canals. Nine other canal developments have been decommissioned as of 2020.

The Holyoke dam is located at the mouth of the canal system and is the only dam associated with the project. There are no downstream dams on the Connecticut River although several are located upstream including Turner’s Falls and Vernon (LIHI #40), the two closest hydroelectric projects. The Open Square Project (LIHI #86) is also located within the canal system.

The project includes Holyoke Dam and eleven developments on the three levels of the canal system, with a combined capacity of 46.946 MW:

  • Holyoke Dam: The dam is a rubble masonry structure finished with ashlar granite, extending 1,020 feet from bank to bank. Founded on bedrock, it is 30 feet high. In 2001, the project owner installed five 3.5-foot-high, inflatable flashboard sections to replace the wooden flashboards. The inflatable flashboard system extends across the entire crest, except at the south end adjacent to the powerhouse intake, where a 25-foot-wide bascule gate is located. The flashboard system helps to minimize reservoir fluctuation and ensure run-of-river operations.
  • Hadley Falls: The station is integral with the Holyoke Dam’s south abutment. Four gated openings admit water to two 28-foot-diameter reinforced concrete penstocks that serve the two generating units. Hadley Unit 1, the older 1950 unit, consists of a full Kaplan turbine and a 15.8-MW generator. Hadley Unit 2 consists of a turbine with a fixed blade propeller and a 15-MW generator. Flows passed through the Hadley Falls Station are discharged into a 2,750-foot-long tailrace, a walled channel between the shore and the riverbed.
  • Between First and Second Levels:
    • Boatlock: The powerhouse structure is an L-shaped building with a concrete substructure and a brick superstructure. It dates from the early1920s and houses one 700-kW unit, one 1,200-kW unit, and one 1,440-kW unit. All are vertical axis Francis units. The 1,200-kW unit underwent a complete generator overhaul and rehabilitation from June 2014 to May 2015.
    • Skinner: The station is located 1,600 feet south of the former Beebe-Holbrook Station and is housed in a non-project building. The installation dates from 1924. Water is delivered through a 150-foot-long, 9-foot diameter steel penstock. There is one 300-kW vertical axis Francis unit.
    • Holyoke 1: The powerhouse is a brick structure constructed in 1893. It contains two 230-kW and two 270-kW turbine generators. Other facility works include two steel penstocks 10 feet in diameter and 36.5 feet long and two tailraces 328.5 feet long and 20 feet wide.
    • Holyoke 2: This facility commenced operation in 1938. Project works include an intake at the wall of the Holyoke first level canal; two parallel 9-foot diameter steel penstocks each 240 feet long; one surge tank about 17 feet high and 10 feet in diameter; a powerhouse containing one vertical turbine-generator unit rated at 800 kW; and two parallel brick arched tailrace conduits, each 9 feet wide, 10 feet high and 120 feet long, discharging into the Holyoke second level canal.
    • Holyoke 4: This facility includes two 7-foot-diameter, 76-foot-long penstocks which draw water from the first level canal to the powerhouse equipped with two 375-kW generating units. Two 13-foot-wide, 300-foot-long tailraces discharge into the second level canal.
  • Between Second Level and the Connecticut River:
    • Riverside: The station has two distinct powerhouses made of concrete and brick. Units 4-7 are housed in one structure. Unit 4 is an 880-kW turbine-generator and Unit 5 is a 600-kW turbine generator; both are horizontal Francis turbines. Unit 6 is also a horizontal Francis unit rated at 600 kW but has been partially dismantled and placed in deactivated reserve status. Unit 7 is a 1,560-kW vertical-axis Francis turbine-generator. Unit 8 is housed in a separate powerhouse and is a vertical axis propeller turbine-generator rated at 4 MW.
    • Valley Hydro (Holyoke 5): Project works consist of a gated intake with trashracks; two 75-foot-long, 6.5-foot-diameter steel penstocks; a refurbished vertical Kaplan turbine-generator rated at 790-kW; a 375 foot long, 16.5 foot wide, and an11-foot-high arched brick-lined tailrace tunnel.
  • Between Second and Third Levels:
    • Holyoke 3: The station commenced operation in 1940 and includes an intake trashrack about 47 feet long and 11 feet high; two head gates about 11 feet square; two low pressure brick penstocks, each roughly 85 feet long and 93 square feet in cross section; a reinforced concrete powerhouse which houses one turbine generator unit rated at 450 kW; and an open tailrace about 118 feet long, 30 feet wide, and 10 feet deep.
  • Between Third Level and Connecticut River:
    • Chemical: The facility is located in a non-project industrial building with water delivered through a masonry flume about 260 feet long and 22 feet wide. The facility’s building is constructed of concrete and brick. There are two generating units, one a vertical-axis Kaplan set rated at 800 kW and the other a vertical-axis fixed blade set, also rated at 800 kW. The units were installed in 1935. The tailwater is carried to the river by two covered masonry flumes, each 125 feet long, 15 feet wide, and 9.5 feet high.

The project operates in run-of-river mode. Inflows to Holyoke Dam are highly regulated by upstream operations at Turner Falls and Vernon. Impoundment fluctuations are limited to 1.2 feet for protection of the endangered Puritan tiger beetle. Minimum flows of 840 cfs are provided into the three channels of the bypass reach and adjusted up to 1,300 cfs for the fish passage season. A total discharge of 550 cfs is also released into the canal system – 150 cfs for the operation of the downstream fish passage facility and 400 cfs for protection of aquatic biota, specifically mussels. The flow regimes were developed in consultation with Massachusetts Department of Environmental Protection (MADEP) and Massachusetts Division of Fish and Wildlife (MADFW).

Waters within the project reach are listed as impaired for E. coli, PCBs in fish tissue, and total suspended solids. Consultation with MADEP concluded that none of the listed impairments are contributed to by the project. The project monitors water quality at the project developments and reports annually to MADEP with the results.

Upstream fish passage is provided for migratory fish and American eel. The passage facility consists of two fish lifts which have been successful in passing shortnose sturgeon (a federally endangered species) and other anadromous species (American shad, Atlantis salmon, sea lamprey, and river herring) and four ramp traps provide passage of American eel. A downstream fish passage louver facility is located in the canal about 550 feet downstream of the canal gatehouse to prevent fish from entering the canal system. An eel ramp, bypass pipe, bypass weir and spillage provide adequate downstream passage for migratory species.

The project lands are completely located within a heavily developed, urban environment. No lands of significant ecological value are found in the project area. The project developed a Shoreline Erosion Remediation Plan which included provisions for inventorying, evaluating, monitoring, and remediating shoreline erosion problems at the project.

Threatened or endangered species potentially present in the project vicinity include the Puritan tiger beetle, bald eagle, yellow lampmussel, Atlantic sturgeon, and shortnose sturgeon. One of the primary reasons the project modified operations from peaking to run-of-river was to protect the Puritan tiger beetle populations that were found along the project boundaries. This operational modification also helped enhance downstream habitat for aquatic species. The National Marine Fisheries Service was consulted to determine the impact of the project on sturgeon populations. There is potential for critical habitat to occur downstream of the project but outside of the project boundary. Thus, operations have generally benefited the downstream flow regime, enhancing the habitat and minimizing any adverse impacts.

The Holyoke and South Hadley canal systems are both listed as Historic Districts on the National Register of Historic Places. Unfortunately, upgrading of the fish passage facilities in 2015 resulted in adverse impacts to a submerged timber crib dam and a 1950s-era cofferdam, both contributing elements to the Holyoke Hydropower System Historic District. The project owner collaborated with the State Historic Preservation Office (SHPO) to preserve photographs of the resources and salvage some pieces of wood from the timber crib dam as part of it had to be removed in the passage facility upgrade. This was done in coordination with the Holyoke Historical Commission. Additionally, the historic Texon Mill was demolished after several failed attempts at adaptive reuse of the building. An agreement was made between the Army Corps of Engineers, the SHPO, and the South Hadley Selectboard and Historic Commission to demolish the mill, clean up the site, and install recreational and public access improvements (Texon Mill Park).

Recreational resources at the project include walking trails, picnic areas, fishing access, a canoe portage, and a visitor center. Public access is provided free of charge.

PLUS-Standard: The project owner voluntarily added the Texon Mill park and a fishway visitor center. The project has permitted camps on project land and funds a seasonal river ranger.

Project Name FERC No. FERC License Term
Installed Capacity (MW) Average Annual Generation (MWH)
Hadley Falls 2004 1999 – 2029 30.61 186,112
Boatlock Station 2004 1999 – 2029 3.34 12,745
Skinner Station 2004 1999 – 2029 0.3 1,389
Chemical 2004 1999 – 2029 1.6 4,107
Riverside 4-7 2004 1999 – 2029 3.04 13,515
Riverside 8 2004 1999 – 2029 4.0 22,177
Holyoke 1 2386 2020-2060 1.0 4,730
Holyoke 2 2387 2020-2060 0.8 3,569
Holyoke 3 2388 2020-2060 0.45 3,206
Holyoke 4 7758 2006-2039 0.75 3,470
Valley Hydro (Station No. 5) 10806 1990-2030 0.79 3,697


Compliance Status

The Certificate includes the following facility-specific conditions:

Condition 1: As related to the goals set forth in License Article 405, the Owner shall evaluate the need to revise its modified run-of-river operation and update the Comprehensive Operations and Flow Plan (COFP) if there is a material change to the operation of the Turner Falls and Northfield Pump Storage projects because of the FERC relicensing of those upstream facilities. The Owner shall notify LIHI within 30 days of the licensing of those facilities and indicate its planned response.

Condition 2: The Owner shall: (a) notify LIHI within 30 days of any communication from a resource agency or FERC that its fish passage facilities are not providing safe and effective upstream or downstream passage and include with the notification a copy of the communication and a statement as to the Owner’s planned response and schedule for remedying deficiencies; and (b) provide a summary report on the status of fish passage activities over the prior year when filing the LIHI annual compliance statement (see Section 5.2.3 of the Handbook), which shall include any information on related studies/evaluations, FERC actions, agency communications/recommendations, and any plans for design and/or construction of new or modified facilities. LIHI reserves the right to modify this certification as necessary to assure that its upstream and downstream fish passage standards are being met.  This condition pertains to fish passage issues at all the Holyoke units, including the canal units.  Optional: If fish passage effectiveness is proven successful before the end of the eighth year of certification, then LIHI will award two additional years to the term of the certificate, related to satisfaction of a second PLUS standard.

Condition 3: The Owner shall notify LIHI within 30 days of any communication from a resource agency of a need to modify its management or operation of the hydroelectric system to assure protection of Atlantic sturgeon and its habitat. The notification shall include a copy of the communication and a statement as to the Owner’s intended response.

2023: No material changes or compliance issues were identified. The project remains in compliance based on the annual review. For Conditions 1 and 3, the project reported no change in status. For Condition 2, the project reported filing annual upstream passage reports.

2022: No material changes or compliance issues were identified. The project remains in compliance based on the annual review. For Conditions 1 and 3, the project reported no change in status. For Condition 2, the project reported filing annual upstream passage reports.

2021: There were no reported changes or compliance issues. The project remains in compliance based on the annual review. For Conditions 1 and 3, the project reported no change in status. For Condition 2, the project reported filing annual upstream passage reports.

2020: There were no reported changes or compliance issues. The project remains in compliance based on the annual review. For Conditions 1 and 3, the project reported no change in status. For Condition 2, the project reported filing annual upstream passage reports.

2019: There were no reported changes or compliance issues. The project remains in compliance based on the annual review. For Conditions 1 and 3, the project reported no change in status. For Condition 2, the project reported filing annual upstream passage reports.

2018: There were no reported changes or compliance issues. The project remains in compliance based on the annual review. For all conditions, the project reported no change in status.

2017: There were no reported changes or compliance issues. The project remains in compliance based on the annual review. For all conditions, the project reported no change in status.

Certification History

January 1, 2022: The LIHI Certificate term has been extended in accordance with Revision 2.05 of the LIHI 2nd Edition Certification Handbook issued January 1, 2022. Refer to the facility table above for the new term.

September 28, 2017:  The 30 day appeal window for the Holyoke Hydroelectric Project has now ended and no appeals were filed. Therefore, the preliminary decision is now final and the Holyoke Gas & Electric Department Hydroelectric System has been approved for an 8-year term, effective January 1, 2017 and expiring January 1, 2025 with an opportunity to extend the term to January 1, 2027.

August 24, 2017:  LIHI has issued a Preliminary Certification Decision that the Holyoke Gas & Electric Department Hydroelectric System (FERC Nos 2004, 2768, 2766, 2771, 2386, 2387, 2388, 7758, 10806) continues to satisfy the LIHI Certification Criteria. As provided for in Section 4.2.5 of the LIHI 2nd Edition Handbook, the Preliminary Certification Decision, 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.  Only individuals or organizations that commented on the initial Application Package may file an appeal.  In addition, applicants may appeal conditions or decisions in a similar manner. 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 the final certification for the facility and post a notification of certification on the LIHI website.  Once final, the effective certification date for the Holyoke Gas & Electric Department Hydro System is August 31, 2017 for an eight (8) year term (with the possibility of an additional two (2) years after satisfaction of Condition 2) which will expire on January 1, 2025.

April 21, 2017: The Low Impact Hydropower Institute has received a complete application for a new term of Low Impact Certification for the Holyoke Hydroelectric project. The application materials can be found in the Files section below. LIHI is seeking public comment on this application.  Specifically, we are interested in knowing whether you think the Holyoke project meets the LIHI Low Impact Certification Criteria, as revised in the 2nd Edition Handbook released in March 2016.  Please review the program and criteria in LIHI’s revised Handbook and then review the Project’s 2016 application materials posted on the project page. 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 “Holyoke Project Comments” in the subject line, or by mail addressed to the Low Impact Hydropower Institute, PO Box 194, Harrington Park, New Jersey 07640.  Comments must be received at the Institute on or before 5 pm Eastern time on June 21, 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.

July 26, 2012: The Holyoke Hydropower System has been certified as low impact for a five year term, effective January 1, 2012 and expiring January 1, 2017, with the following conditions:

  • Condition satisfied. If HG&E does not meet any of the downstream fish passage design and implementation deadlines that fall within the 5-year term of certification, LIHI will suspend certification unless HG&E demonstrates to LIHI that the resource agencies believe good cause exists for the schedule delay. Any subsequent re-certifications of the Facility will be dependent on HG&E’s passage facilities meeting effectiveness targets set by the agencies. HG&E shall either 1) restore the Shad Derby to two May weekends per year starting with May 2013 and at a minimum through the term of this certification, or 2) shall sponsor the Shad Derby for only one May weekend per year but only if the change from two weekends to one is approved by FERC based on an application to amend the Project 2004 recreation plan, with full consultation of Resource Agencies and interested NGOs. Should HG&E seek to amend the recreation plan, the Shad Derby shall be sponsored for two weekends per year until such time as FERC acts. HG&E shall inform LIHI of its decision by October 1, 2012. If it chooses to seek to amend the recreation plan, it shall notify LIHI of FERC’s final decision within 30 days of issuance. Continued non-compliance with this element of the recreation plan shall result in immediate revocation of this certification. Should HG&E obtain a written determination from FERC that the change from two weekends to one is not subject to FERC approval, HG&E shall provide LIHI with a copy of the determination and this condition shall become nullified.

May 14, 2010: The Holyoke Gas and Electric Department has submitted an application for certification of the HG&E Hydroelectric System.

Certification Files

2017 Recertification

2012 Certification

Key Documents