LIHI Certificate #188 - Cascade Project, New Hampshire
| Project Name | Cascade |
| LIHI Certificate No. | 188 |
| LIHI Certificate Term | August 31, 2026 – August 30, 2036 |
| Owner | Great Lakes Hydro America, LLC, a subsidiary of Brookfield Renewable Energy Group |
| State | New Hampshire |
| Location | Located at river mile 135.6 on the Androscoggin River in Berlin and Gorham, Coos County |
| Installed Capacity | 8.115 MW |
| Average Annual Generation | 49,897 MWh |
| Facility Type | Run-of-river |
| FERC No. | P-2327 issued in 2025, expires 08/31/2065 |
The Cascade Project is located on the Androscoggin River in the city of Berlin and the town of Gorham, New Hampshire. The dam and a grinder room were originally constructed in 1903 by the Berlin Mills Company to provide hydro-mechanical power for paper making activities. The grinder room was converted to a hydroelectric generating powerhouse between 1913 and 1918 which included the replacement of the hydro-mechanical units with hydroelectric turbine/generators. Hydroelectric energy was first produced in 1914.
The Androscoggin River, spanning 178 miles, drains 3,450 square miles within New Hampshire and Maine. It joins the Kennebec River at Merrymeeting Bay in Maine before emptying into the Gulf of Maine and subsequently the Atlantic Ocean. The Project is one of several hydroelectric projects within an 11-mile reach of the Androscoggin River between Berlin and Shelburne, New Hampshire including Sawmill (LIHI #173), Cross Power (LIHI #174), Upper Gorham (LIHI #175), Gorham (LIHI #153), and Shelburne (LIHI #176). The Cascade project is located just downstream of the Cross Power Project (LIHI #174) and immediately upstream of the Upper Gorham Project (LIHI #175).
The dam is in the same configuration as it was in 1903. It is a 583-foot-high concrete gravity dam consisting of:
- A 15-foot-wide concrete abutment which extends for about 20 feet upstream and 30 feet downstream perpendicular to the end of the spillway,
- An ogee spillway section, 313 feet long with 3-foot-high flashboards,
- A forebay gate structure, 168-feet-long by 15-feet-wide. It consists of 15 three-feet-wide concrete piers and a concrete deck with wooden gates, each 9-feet-wide and 11-feet-high,
- An abutment adjacent to the forebay gate structure consisting of two parallel 3-foot-wide concrete retaining walls with earth fill. The retaining walls extend approximately 88 feet, including 77 feet located inland of the riverbank,
- A forebay, downstream of the forebay gate structure, approximately 300-feet-long by 240-feet-wide with a maximum depth of 24 feet. The forebay wall is a concrete gravity structure that extends approximately 326 feet downstream. The wall has a maximum height of 41 feet, with a 4-foot, 11-inch-wide crest.
Within the forebay wall is:
- A deep gate located about 90 feet downstream.
- A 4-foot-wide by 2.5-foot-deepsluiceway located about 193 feet downstream.
- A concrete platform located on top of the forebay wall, measuring 19-feet by 24-feet, to support an electrical tower with transmission lines.
- A steel framed brick and block powerhouse, measuring 135-feet-long, 43-feet-wide, and 67-feet-high with a concrete structure addition measuring 19-feet by 24-feet. Three penstocks lead from the head gates to the three Francis turbines with a combined capacity of 8.115 MW.
A 400-foot-long bedrock channel bypass reach is fed by the water passing over the spillway.
The project operates in a run-of-river mode and impounds a 28-acre reservoir. The impoundment is allowed to fluctuate over a 6-inch range. The project provides a minimum flow of 6 cfs or inflow, whichever is less, through an orifice in the spillway flashboards to provide stable habitat for resident species. This minimum flow regime was developed in consultation with the US Fish and Wildlife Service and New Hampshire Fish and Game Department.
Waters within the project reach are designated as Class B, suitable for fishing, primary contact recreation, and water supply after treatment. The project waters are listed as impaired due to prior discharges from several paper mills. Given run-of-river operations, the project is unlikely to adversely impact water quality.
The Androscoggin River is not accessible to diadromous fish species in the project reach due to downstream natural falls – Lewiston and Rumford Falls, in the Maine portion of the river. American eel are present in the lower reaches of the Androscoggin River though none have historically reached the upper sections of the river. The project area supports cold-water fishery habitat. New Hampshire Department of Fish and Game annually stocks brook, rainbow, and brown trout upstream of the project. Resident river species include fallfish, smallmouth bass, white sucker, longnose dace, common shiner, spottail shiner, and yellow perch. Downstream passage can occur by means of spillway flow, low-level gate releases, and power intake flow through the trashracks. The project does not impede the successful completion of resident fish life cycles.
The limited project lands consist of those associated with project structures. The project is surrounded by low density residential and commercial development out the outskirts of the City of Berlin. The project’s run-of-river operations provides protection of the shoreline areas. The project is also subject to the New Hampshire Shoreland Water Quality Protection Act which governs shoreland uses within a 250-foot buffer of the high-water mark.
Threatened or endangered species potentially present in the project vicinity include northern long-eared baty, Canada lynx, and the proposed for listing tri-colored bat and monarch butterfly. The project avoids removing trees from April 15 through October 31, unless emergency tree removal for public safety is necessary.
The project’s dam and powerhouse are eligible for listing on the National Register of Historic Places (NRHP). No Native American lands, known as traditional cultural properties, or NRHP-eligible tribal resources are present within the Project boundary. The project operates under a Programmatic Agreement (PA) in consultation with the State Historic Preservation Office. The PA and related Historic Properties Management Plan (HPMP) provides provisions detailing annual monitoring and reporting concerning repair and improvement activities conducted as well as any scheduled activities for the upcoming year.
No recreational resources are provided in the project’s limited area. However, an impoundment access area is owned and operated by the City of Berlin outside the Project boundary. This area provides scenic views, a gravel hand-carry boat access, and bank and boat fishing.
Compliance Status
The Certificate includes the following facility-specific conditions:
Condition 1: The Facility Owner shall submit the final Operational Compliance Monitoring Plan (OCMP) to LIHI once it has been approved by resource agencies and FERC. In annual compliance submittals to LIHI the Facility Owner shall submit a summary of all planned and unplanned operational deviations that occurred during the year along with evidence of resource agency consultation and comments received.
Condition 2: The Facility Owner shall submit the final Historic Properties Management Plan to LIHI once it has been approved by the SHPO and FERC. In annual compliance submittals to LIHI, the Facility Owner shall report on any consultation that occurred during the year related to ground-disturbing or other activities subject to the HPMP.
Condition 3: The Facility Owner shall consult with the City of Berlin on the proposed installation of a safety chain and/or a gate across the boating put-in at the impoundment access area with safety signage that states when the site is open and closed. If the City feels it is needed, the Facility Owner shall provide LIHI with a plan and schedule for implementation. If the City agrees that a chain/gate or signage is not needed, the Facility Owner shall provide documented evidence of that agreement.
2026: Annual reporting for the current Certificate has not yet taken effect.
Certification History
August 18, 2026: The Low Impact Hydropower Institute has preliminarily approved Low Impact recertification for the Cascade Hydroelectric Project. The mid-term review applications and reviewer report are available below. The certification includes three conditions included in the review report to ensure that FERC relicensing implementation measures are timely met. The 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 “Cascade Project” in the subject line, or by mail addressed to the Low Impact Hydropower Institute, 68 Harrison Ave Ste 605, PMB 113938 Boston, Massachusetts 02111-1929. 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 September 17, 2026. If no appeal requests are received the new certification term will be March 1, 2026 through February 29, 2036.
April 28, 2026: The Low Impact Hydropower Institute has received a complete application (see below) for a mid-term review of the Cascade Project. The Project is one of several LIHI Certified projects located on the upper Androscoggin River in New Hampshire that were issued new FERC licenses in September 2025. In accordance with Section 5.3.4 of the 2nd Edition LIHI Handbook, issuance of a new license constitutes a “material change” and triggers a mid-term LIHI Certification review. LIHI is seeking public comment on this application. Specifically, we are interested in knowing whether you think the Project continues to meet the LIHI Low Impact Certification Criteria, as revised in the 2nd Edition Handbook. 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 comments@lowimpacthydro.org with “Cascade Comments” in the subject line, or by mail addressed to the Low Impact Hydropower Institute, 68 Harrison Ave. Ste 605, PMB 113938, Boston MA 02111-1929. Comments must be received by 5 pm Eastern time on June 27, 2026 to be considered. All comments will be posted to the website, and the applicants will have an opportunity to respond. Any response will also be posted.
May 19, 2022: The decision to certify the Cascade Project became final after the close of the appeals period on May 18, 2022 with no appeals filed. The Certification term is from March 1, 2022 – February 29, 2032.
April 18, 2022: The Low Impact Hydropower Institute (LIHI) has preliminarily approved the Cascade Project for a 10-year term of Low Impact Certification. 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 comments@lowimpacthydro.org with “Cascade Project” in the subject line, or by mail addressed to the Low Impact Hydropower Institute, 1167 Massachusetts Ave, Office 407, 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 May 18, 2022. If no appeal requests are received and the decision becomes final, the Certification term for the Project will be March 1, 2022 through February 29, 2032.
February 7, 2022: The Low Impact Hydropower Institute has received a complete application for Low Impact Certification of the Cascade 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 “Cascade 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 on or before 5 pm Eastern time on April 8, 2022 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.
Certification Files
2026 Mid-Term Review
2022 Certification