LIHI Certificate #120 – Gregg’s Falls Project, New Hampshire

The Gregg’s Falls Project is located on the Piscataquog River near the town of Goffstown, New Hampshire. The site was historically used for the generation of electrical energy and the project dam was constructed in 1919. It was operated as a peaking waterpower facility until the 1970s, when the powerhouse was decommissioned. In 1985, a major refurbishment took place, which included the installation of two new turbines and generators and the replacement of all electrical and control equipment. The Piscataquog River is within the Merrimack River Basin that encompasses approximately 1,799 square miles. The Piscataquog is approximately 70 miles long and consists of three branches. The three branches converge upstream of the Project. The river’s confluence with the Merrimack River is approximately 2 river miles downstream of Amoskeag dam, part of the Merrimack River Project which includes Hooksett (LIHI #162). The Lowell Project (LIHI#142) the next downstream project on the Merrimack mainstem in Massachusetts. The only downstream hydropower facility on the Piscataquog River is Kelley’s Falls.

The project consists of an existing earthfill and concrete gravity dam, 1,360 feet long and 60 feet high. The concrete spillway is topped by 1.5-foot-high flashboards. Intake structures, fish passage facilities, a concrete penstock 31.75 feet long with an oblong shape transitioning to circular shape are also project components. The powerhouse contains 2 turbines and 2 new generators with a total installed capacity of 3.479 MW.

The project operates in an instantaneous run-of-river mode and impounds a 136-acre reservoir. The project has a seasonal drawdown of 1.5 feet and run-of-river operations continue at the lower elevation throughout the winter and spring. Flashboards are removed after drawdown and are replaced in the spring after the freshet. Impoundment refill rates are customarily limited to 10% of inflow with 90% of inflow being passed over the spillway until the summer impoundment level is reached. Drawdowns are scheduled by New Hampshire Department of Environmental Services (NHDES), the owner of the dam. The project provides a 20-cfs tailrace base flow, or inflow if less. The US Fish and Wildlife Service conducted a site evaluation and determined the flow regime is adequate to protect aquatic habitat.

Project Name  Gregg's Falls
LIHI Certificate No. 120
LIHI Certificate Term January 26, 2020 - January 25, 2028
Owner Gregg's Falls Hydroelectric Associates Limited Partnership, a subsidiary of Eagle Creek Renewable Energy, LLC
State New Hampshire
Location Located at River Mile 30 (of 37) on the Piscataquog River in New Hampshire.
Installed Capacity 3.479 MW
Average Annual Generation 10,542 MWh
Facility Type  Run-of-river
FERC No. P-3180 exempt 1983

Waters within the project reach are designated Class B, best used for agriculture, boating, fishing, water-contact recreation, wetland and fish nursery support, and hydropower. The waters are listed as impaired for pH due to the effects of atmospheric deposition and low buffering capacity as determined by NHDES. The project coordinated with NHDES to develop a water quality monitoring plan and subsequent water sampling was conducted in 2016. NHDES confirmed the project was meeting water quality standards.

Migratory species historically present in the Piscataquog River include alewife, American shad, blueback herring, Atlantic salmon, and American eel. Currently, the downstream dam creates a barrier to upstream passage. However, the project has committed to implementing upstream passage should it be requested by agencies in the future. Downstream passage is facilitated by a passage pipe. The downstream passage pipe is no longer in use as the passage was primarily utilized by Atlantic salmon, but restoration efforts were discontinued in 2013 by US Fish and Wildlife Service. Downstream fish bypass passage facilities for adult and juvenile river herring are provided in all years when river herring are stocked upstream. The project must construct and operate American eel passage facilities should a prescription be made by USFWS or NH Fish and Game.

The project property consists of roughly 49 acres. The area is relatively developed including residential and mixed-use commercial properties. Downstream, the shoreline is primarily forested with little development. The Piscataquog River is a state-protected river under the New Hampshire Rivers Management and Protection Program. Over 4,300 acres of land along the river are further protected by conservation groups, agencies, and private landowners. Proposed development activities are subject to review by the Piscataquog River Local Advisory Committee and a 250-foot buffer from the river’s edge must be maintained per the NH Shoreland Water Quality Protection Act.

Threatened and endangered species that potentially within the project property include Northern long-eared bat, brook floater mussel and wood turtle (a state species of special concern). Bald eagle, black-billed cuckoo, bobolink, prairie warbler, snowy owl, and wood thrush may also be present, and the project complies with all provisions under the Migratory Bird Treaty Act and the Bald and Golden Eagle Protection Act. New Hampshire Fish and Game has confirmed that due to the operations of the project and its small footprint, the project is unlikely to impact listed species.

The project has consulted with the New Hampshire Division of Historical Resources to confirm that no historical or archaeological resources are expected to be impacted by routine operation of the project. The agency also noted that cultural resource surveys must be conducted should any site alterations occur.

Recreational resources at the project include boating, fishing, paddling, and whitewater boating. Public access is provided free of charge where safe.

PLUS-Standard: The owner coordinates with the local kayaking group on a convenient time and release date of annual drawdowns which support whitewater boating, to ensure there are not conflicting drawdowns or other paddling events. The owner also coordinates with NHDES on the specifics of the drawdown.


Certification History

April 17, 2020: The decision to recertify the Gregg’s Falls Project became final after the close of the appeals period on April 16, 2020 with no appeals filed. The Certification term is from January 26, 2020 – January 25, 2028. The Certificate includes the following condition:

  • Condition 1: If the Facility owner receives notification from FWS or NHFG during the term of LIHI Certification that upstream or downstream passage is required, the owner shall inform LIHI within 90 days of the notification and provide updates on the status of agency consultation, any studies conducted, design plans, and a schedule of implementation in annual compliance submittals.

March 17, 2020:  The Low Impact Hydropower Institute (LIHI) has preliminarily approved the Gregg’s Falls Project (LIHI #120) for a new 8-year term 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 comments@lowimpacthydro.org with “Gregg’s Falls Project” in the subject line, or by mail addressed to the Low Impact Hydropower Institute, 329 Massachusetts Ave, Suite 6, Lexington, MA 02420.

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 16, 2020. The full application and reviewer’s report are available below.

If no appeal requests are received and the decision becomes final, the Certification term for the Project will be January 26, 2020 through January 25, 2028.

January 3, 2020: The Low Impact Hydropower Institute has received a complete application for Low Impact Recertification of the Gregg’s Falls Hydroelectric Project.  LIHI is seeking public comment on this application.  Specifically, we are interested in knowing whether you think the Project meets the LIHI Low Impact Certification Criteria, as revised in the 2nd Edition Handbook.  Please review the program and criteria in LIHI’s revised Handbook and then review the Project’s application materials below.

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 “Gregg’s Falls Project Comments” in the subject line, or by mail addressed to the Low Impact Hydropower Institute, 329 Massachusetts Avenue, Suite 6, Lexington, MA 02420.  Comments must be received on or before 5 pm Eastern time on March 3, 2020 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.

June 24, 2015 – Executive Director Michael J. Sale, using authority delegated from the LIHI Governing Board and a full review of the Application Reviewer’s report and all public comments and additional materials provided by the Applicant, has determined that the Gregg’s Falls Hydroelectric Project (FERC No. P-3180) satisfies the LIHI Certification Criteria. The effective certification date for the Gregg’s Falls Project is January 26, 2015 for a five (5) year term, which will expire on January 26, 2020, with the following conditions:

  • Condition satisfied in 2017. Condition 1. To confirm compliance with possible new flow requirements, the Facility Owner shall provide LIHI with documentation of the USFWS’s required flow regime for the Project, the final schedule for implementing the Operations and Flow Monitoring Plan, and approval from USFWS and NHF&GD of this Plan. These shall be provided within 30 days of each item’s completion. In its annual compliance report, the Facility Owner shall provide a statement of compliance with the Operations and Flow Monitoring Plan and an explanation of any deviations from the Plan requirements.
  • Condition satisfied in 2017. Condition 2. To confirm that the project waters are meeting all numerical state standards for water quality, additional sampling for all parameters, including but not limited to DO, chlorophyll and pH as outlined in a sampling plan to be developed by NHDES, shall be conducted in 2015. The sampling plan, results of these studies and an analysis by NHDES regarding compliance with state standards shall be provided to LIHI within 30 days of completion of NHDES’s determination. All additional water quality sampling required by NHDES shall be completed by December 31, 2015.
  • Condition satisfied in 2016. Condition 3. To confirm compliance with the MOA regarding fish passage, the Facility Owner shall provide LIHI with copies of any notification that they receive from state or federal resource agencies that require construction of the downstream passage and protection facilities for river herring and American eel. LIHI shall be notified of any such fish passage requirements within 30 days of receipt of that notification. Further, the Facility Owner shall keep LIHI informed on the status of activities conducted to meet these requirements within the designated timeframe, including any interim deadlines (e.g., approval of construction plans, effectiveness testing completion, etc.) in their annual compliance report to LIHI.

January 26, 2015 – The Low Impact Hydropower Institute (LIHI) received an application from Eagle Creek Renewables for Low Impact Certification of the Gregg’s Falls Hydroelectric Project, FERC P-3180, located on the Piscataquog River, in the state of New Hampshire.