The Open Square project is located on the Connecticut River and the Holyoke Canal System, a man-made structure constructed for the purpose of power generation. The canal system consists of three levels, referred to as First, Second, and Third Level Canals.

Project Name Open Square
LIHI Certificate No. 86
LIHI Certificate Term
December 5, 2016 – December 5, 2026
Owner Open Square Properties, LLC
State Massachusetts
Location Located on the Connecticut River and the Holyoke Canal System.
Installed Capacity 0.54 MW
Average Annual Generation 3,000 MWh
Facility Type conduit
FERC No. n/a, FERC non-jurisdictional

The system is tiered with the first canal at the highest elevation and each subsequent canal at a lower elevation. A series of subsurface sluiceways extend between each of the canals. Many of the sluiceways contain rotating turbines that generate power. The sluiceways and canals are not considered to be navigable waterways under the Clean Water Act.

Open Square is a mixed-use development of seven historic mill buildings containing 685,000 square feet of floor area on an 8-½ acre city block located between the First and Second Level Canals of the Holyoke Gas & Electric (HG&E) Hydropower System. The Project occupies a small amount of space within the complex.

The canal system consists of three levels. The Project utilizes the 20 feet of head between the First Level Canal at elevation 97.5 feet msl and the Second Level Canal at elevation 77.5 feet msl. The First Level Canal is a subsystem about 6,500 ft long and running through the city of Holyoke.

HG&E owns and operates hydroelectric facilities at Holyoke Dam (the Hadley Falls Station) and in the Holyoke Canal System. Within the canal system, HG&E owns eighteen stations, two of which, Crocker Mill A and B and Crocker Mill C, are no longer operating and are scheduled for decommissioning; as with Open Square, most of the HG&E canal system hydroelectric units are located within buildings that are used for unrelated light commercial or industrial purposes. Six HG&E stations utilize water from the First Level Canal, and there is a second privately owned station, Parsons, which is similarly located but no longer operates.

The Canal System begins at a gatehouse structure located directly upstream of Hadley Falls Station. A downstream fish passage louver facility is located starting about 554 feet downstream of the canal gatehouse. The full-depth louver rack is angled downstream across the canal and ends at a bypass facility and pipe. The pipe transports migrating fish to the Hadley Falls Station tailrace. The No. 1 Overflow structure, which is located immediately downstream of the gatehouse, discharges water directly back to the Hadley Falls Station tailrace, or to the fish lift attraction water.

Open Square (a.k.a. Aubin Station) consists of two powerhouses each with single units, referred to as the D-Wheel and the G-Wheel. The D-Wheel Powerhouse is located in the northeast corner of the lower level floor of Mill 2 at Open Square. The D-Wheel unit consists of a Leffel 33-inch ‘Z’ Vertical Francis Turbine in a pressure flume with an Electric Machine Company synchronous generator installed in 1933. The system generates an average of 260 kW.  The G-Wheel powerhouse is located in the northwest corner of the lower level floor of Mill 5. The unit consists of a Leffel 33-inch ‘Z’ Vertical Francis Turbine in a pressure flume with a General Electric synchronous generator installed in 1928. The system generates an average of 280 kW.

D Wheel Raceway

G Wheel Raceway











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 the Falls by diverting water from the Connecticut River to mills for mechanical power for manufacturing. Open Square’s first mills were built and operated by the South Hadley Falls Company before the company went bankrupt in 1854 (Mill 1 dates to 1848). The first hydroelectric turbine was installed within the canal system in 1888. The Hadley Falls 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.

There are a total of twenty hydroelectric generating stations currently in service on the Holyoke Canal System including two owned by Open Square and seventeen that are owned and operated by HG&E [Holyoke Gas & Electric, a department of the City of Holyoke]. The canal system begins with the canal gatehouse structure located between the Hadley Falls Station and the western shore.

The Holyoke Dam is the first dam encountered by fish migrating up the Connecticut River to spawn. Providing safe and adequate passage has been a priority at the Holyoke Project since the late 1800s. Several fish passage ladders were installed between the mid 1800s and the mid-1900s. In 1955 the first fishlift was constructed at the Project. The fish passage facilities have undergone substantial modifications and improvements since that time. Today, the Holyoke Project provides excellent passage for migratory fish in the Holyoke Project area, include Atlantic salmon, American shad, blueback herring, alewife, stripped bass, American eel, lampray and shortnose sturgeon.

Certification History

October 3, 2017:  On October 3, 2017, the 30-day appeal window for the preliminary decision to recertify the Open Square Hydroelectric Project ended with no appeals filed. The recertification decision is therefore final.

The term of Low Impact Certification for the Open Square Hydroelectric Project is from December 5, 2016 and expires on December 5, 2026.

August 25, 2017: On August 24th, LIHI issued a Preliminary Decision that the Open Square Hydroelectric Project continues to meet LIHI Low Impact Certification Criteria. The Certification includes two facility-specific conditions:

Condition 1: The Owner shall monitor the status of the studies being conducted evaluating impacts to American eel and other resident species living in the canal system for the re-licensing of the Holyoke Nos. 1, 2 and 3 Projects (FERC Projects P-2386, 2387 and 2388, respectively). When a new license is issued to these facilities, the Owner shall notify LIHI of the issuance date(s). At that time, LIHI will re-assess whether or not impacts are likely occurring at Open Square, and if so, will consider actions that may be needed at Open Square to maintain its LIHI certification.

Condition 2 (carried forward from 2012 certification): The Owner shall cooperate with the City of Holyoke in the planning and development of the Holyoke Canal Walk. Such cooperation shall accommodate the project’s planned completion within 12-18 months. The status of cooperation for this Canal Walk related bridge project shall be provided to LIHI within 45 days of reaching a mutually agreeable
understanding. A summary of further coordination activities shall be provided in the annual reports to LIHI.

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 https://lowimpacthydro.org/certification-program-html/.

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 Open Square Hydroelectric Project is December 5, 2016 for a ten(10) year term which will expire on December 5, 2026.

June 7, 2017: The Low Impact Hydropower Institute has received a complete application for a new term of Low Impact Certification for the Open Square Hydroelectric Facility. The Open Square Hydroelectric Facility is located in the town of Holyoke, Hampden County, Massachusetts, on the Connecticut River.

LIHI is seeking public comment on this application.  Specifically, we are interested in knowing whether you think the Open Square 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 2017 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 comments@lowimpacthydro.org with “Open Square 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 September 25, 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.

May 3, 2012: The Open Square Hydroelectric Project has been certified as low impact for a five year term, effective December 5, 2011 and expiring December 5, 2016. The following conditions were included with the certificate:

  1. Satisfied (incorporated into standard compliance statement requirements). Open Square Properties LLC shall consult with, and obtain approval from, the State Historic Preservation Office for activities that may have an adverse affect on cultural resources, including excavation, demolition, and structural alteration. Information on such activities shall be included in the annual reports filed with LIHI.
  2. Open Square Properties LLC shall continue to cooperate with the City of Holyoke in the planning and development of the Holyoke Canal Walk, including the grant of easements under reasonable terms. The status of negotiations and construction scheduling shall be provided in the annual reports to LIHI.

Recognizing that there is a concurrent application by Holyoke Gas & Electric Department for its Hadley Falls Station and Canal stations, that this application remains pending at this time, and that the Open Square Hydroelectric Project is inextricably part of the entire generating system at the Holyoke Dam site, LIHI adds the following two special conditions:

  1. Satisfied. If it determines that the project(s) owned and operated by the Holyoke Gas & Electric Department (Hadley Falls station on the Connecticut River and sixteen stations on the Holyoke Canal System) do not qualify for certification, LIHI reserves the right to revoke this certification.    
  2. Satisfied. If within three months from the date of issuance of this certification the Holyoke Gas & Electric Department does not have in place an agency-approved downstream fish passage plan and implementation schedule, this certification shall be suspended effective three months from the date of issuance, and it shall remain suspended until LIHI notifies Open Square Properties LLC that such a plan and schedule have been approved by the agencies and that the suspension is lifted. During the period of suspension, Open Square Properties LLC shall not employ the certification in marketing the power produced.

LIHI reserves the right to suspend certification if the above steps are not completed, if no agreement is reached with the agencies, or if required measures to ensure downstream passage that is appropriately protective of the Atlantic salmon resource, are not made by April 1, 2013.

February 5, 2012: Public comment period on application has been closed.

December 5, 2011: Open Square Properties has submitted an application for the certification of the Open Square Hydroelectric Project. Public comment period has been opened.


2017 Recertification

2011 Certification