LIHI Certificate #192 - High Falls Project, New York

Project Name High Falls
LIHI Certificate No. 192
LIHI Certificate Term October 4, 2022 – October 3, 2032
Owner Copenhagen Hydro, LLC, a subsidiary of LS Power/ Patriot Hydro, LLC
State New York
Location River Mile 7.75 on the Deer River
Installed Capacity 3.43 MW
Average Annual Generation 8,000 MWh
Facility Type Run of river
FERC No. P-3754, exempt 1982

The High Falls Project is located on the Deer River in the Village of Copenhagen, Town of Denmark, Lewis County, New York. Originating at Tug Hill, the Deer River runs for 27 miles northeasterly through north-central New York, feeding into the Black River. The dam was built in 1909 by the Deer River Power Company at High Falls, a 166-foot natural waterfall. Farther downstream are the 25-foot King Falls and the 15-foot Deer River Falls. The King Falls Hydroelectric Project, built in 1953, is located several miles downstream of the High Falls Project.

The project consists of a 175-foot-long and 25-foot-high-concrete gravity dam with 2-foot-high flashboards and an impoundment about 0.6 miles long. Average annual flow is estimated to be 127 cfs. The impoundment is situated directly above High Falls with the penstock following the top eastern ridge line until it drops toward the powerhouse located along the riverbank. The impoundment creates a bypassed reach approximately 0.26 miles long. The intakes have 2.5-inch clear spaced trashracks and a 1,350-ft-long, 6-ft-diameter steel penstock leads to the powerhouse which includes three horizontal Francis turbine-generators. Units 1 and 2 are each rated for 1.5 MW and Unit 3 is an induction unit limited to 0.429 MW which operates either on or off with a hydraulic capacity of 35 cfs. The project operates with a total installed capacity of 3.429 megawatts and generates approximately 8,000 MWh annually.

The project operates in a run-of-river mode and impounds a 4-acre reservoir with negligible storage capacity. A minimum flow of 8 cfs is provided in the bypassed reach from a discharge pipe below the dam crest. Run-of-river operation is maintained by a headpond sensor and programmable logic controller which ramps the generating units accordingly to sustain the impoundment level.

Waters within the project reach are designated as Class C Fresh Water by the New York State Department of Environmental Conservation (NYSDEC). This class of waters is suitable for aquatic habitat, angling, and primary/secondary contact recreation. Agricultural runoff and the upstream wastewater treatment plant may limit recreation in and on the water. NYSDEC conducted macroinvertebrate sampling and confirmed that parameters including dissolved oxygen, temperature, conductivity, and pH are not impacted by the project or the nearby wastewater treatment plant.

The natural High Falls at the project preclude upstream passage for any potential migratory species present in the project area. No current or historical observations of migratory fish species have been made. Resident species include smallmouth bass, rock bass, yellow perch, walleye, northern pike, and chain pickerel.

The project lands consist of roughly 16 acres surrounded primarily by agricultural lands with a forested riverine buffer along the impoundment. The downstream reach is mostly forested with some agricultural use. Of these lands, no ecological significance has been identified. Run-of-river operations mitigate the potential for impoundment erosion and the bypassed reach is not likely to be subject to erosion due to its bedrock composition.

Threatened or endangered species potentially present in the project vicinity include the Indiana bat, Northern long-eared bat, American Hart’s-tongue fern, and bald eagle. No critical habitats for the listed species exist in the project area. Vegetation management is limited to periodic mowing and brush clearing around project structures, activities unlikely to impact bat or eagle habitat. American Hart’s-tongue fern is found in close association to limestone gorges and cool limestone sinkholes in mature hardwood forests. Even if present, the species is unlikely to be adversely impacted due to the run-of-river operations.

The Village of Copenhagen was developed within the Town of Denmark in 1800 when Nathan Munger and his son erected their first gristmill followed by a sawmill the following year, both on the Deer River. The village that grew up around this mill was called Munger Mills, with most of its residents considered Federalists in support of British rule. But after the news of the British attacking Copenhagen, Denmark, the republican villagers agreed in a village meeting to take on the name of Copenhagen to shame local Federalists for their support of the British. The original mills built along the river are no longer standing. In 1890, the worst recorded flood on the Deer River came roaring down from the hills sweeping away all obstacles within reach of its raging torrent. Several buildings, waterwheels, bridges, and dams were carried away. The area is designated an Archeologically Sensitive Area by the New York Cultural Resource Information System, though no National Register of Historic Places listed properties exist within the town or downstream of the project. Project structures could be eligible for listing based on project age.

Recreational resources at the project are limited due to the small project footprint and the height and steepness of the bypassed reach. Informal angling and boating occur in the impoundment and downstream reach. Nearby resources include Adirondack Park, stocked trout streams, and whitewater boating upstream of the project. Public access is provided free of charge where safe and reasonable to do so.

Compliance Status

The Certificate does not include any facility-specific conditions.

2023: No material changes or compliance issues were identified. The project remains in compliance based on the annual review.

2022: Annual reporting for the current Certificate has not yet taken effect.

Certification History

December 19, 2022:  The decision to certify the High Falls Project became final after the close of the appeals period on December 10, 2022 with no appeals filed. The Certification term is from October 4, 2022 – October 3, 2032.

November 10, 2022:  The Low Impact Hydropower Institute (LIHI) has preliminarily approved Low Impact Certification (pending LIHI #192) for the High Falls Hydroelectric Project. 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 with “American Tissue Project” in the subject line, or by mail addressed to the Low Impact Hydropower Institute, 1167 Massachusetts Ave. 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 December 10, 2022. If no appeal requests are received the certification term will be October 4, 2022 through October 3, 2032.

July 15, 2022: The Low Impact Hydropower Institute has received a complete application for Low Impact Certification of the High Falls (Copenhagen) 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.  The Project’s application materials can be found 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 with “High Falls Project Comments” in the subject line, or by mail addressed to the Low Impact Hydropower Institute, 1167 Massachusetts Avenue, Office 407, Arlington, MA 02476.  Comments must be received on or before 5 pm Eastern time on September 13, 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

2022 Certification

Key Documents