The Weybridge Project is situated at the head of a rock-walled gorge where the Otter Creek cascades around a small island, the Weybridge Project is located in the towns of Weybridge and New Haven. The Project forms a compact cluster of buildings and structures around the divided falls at the upstream end of an island. The riverbank corridor within the Project follows the impoundment about 1.5 miles upstream to Huntington Falls (part of Otter Creek Hydro FERC No.2558), and reaches miles downstream from the powerhouse falls. The Vergennes Project (FERC No.2674) is located approximately 12 miles downstream.

Project Name Weybridge
LIHI Certificate Number 98
LIHI Effective and Expiration Dates February 6, 2012
February 6, 2017
(extended to March 31, 2019)
Owner Green Mountain Power Corporation
State Vermont
Location Located in Weybridge and New Haven, Vermont.
Installed Capacity 3.0 MW
Average Annual Generation 13,846 MWH
Facility Type Daily cycling in normal and low flows; run-of-river in high flows
FERC No. 2731

The Project consists of a concrete gravity dam with integral powerhouse, a 62-acre impoundment, transmission facilities and appurtenant facilities.   The dam is 30 feet high and 302.6 feet long with two spillway sections: a 150-foot long west spillway section, topped with a 6-foot high hinged steel flashboard, and abutted by a 20-foot wide and 10-foot high taintor gate; and a 116-foot long east spillway section topped with an automatically-inflated rubber weir. The reservoir is 1.5 miles long, impounding 62 acres with a normal water surface elevation of 174.3 feet msl.

The powerhouse is integral with the dam and has an intake with 3-inch steel trashracks. There is one vertical Kaplan turbine generator with an installed capacity of 3.0 MW. Appropriate generator leads and transformers connect the Project to the interconnected transmission and distribution system at the switchyard located about 100 feet from the powerhouse.

The Project operates as a daily cycling facility during normal and low flow conditions. cycling is suspended from April 1 to June 15 to protect fish spawning. The Project operates in a run-of-river mode when flows exceed its hydraulic capacity of 1,600 cubic feet per second. A diversion structure extends from the downstream end of the dam at Rock Island to another small island at the entrance to the bypass channel, and around another island (Wyman Island), reapportioning the flow in the bypassed (west) and tailrace (east) channels. The diversion structure includes a control weir with stop log slots at the downstream end, at the entrance to the west channel. A 15-foot wide by 3.5-foot high notch in the control weir passes water from the pool formed by the control weir and the diversion structure, downstream into the west channel around Wyman Island.

Weybridge aerial photo

Weybridge aerial photo

Certification History

November 12, 2018: The Weybridge Hydroelectric project has been granted another extension of the current certificate term. The new expiration date is March 31, 2019.

June 11, 2018: The Weybridge Hydroelectric project has been granted another extension of the current certificate term. The new expiration date is September 30, 2018.

November 3, 2017: The Weybridge Hydroelectric project has been granted another extension of the current certificate term. The new expiration date is March 31, 2018.

October 26, 2017: On October 26, 2017, the Low Impact Hydropower Institute (LIHI) received a complete application from Green Mountain Power for the Low Impact Certification of the Weybridge Hydroelectric Project, located in Webridge and New Haven, VT (FERC 2731).

LIHI is seeking public comment on this application. Specifically, we are interested in knowing whether you think the Weybridge project meets the LIHI Low Impact Certification Criteria. The Weybridge application is subject to review using the Criteria in the LIHI Certification Handbook of 2016.  Please review the program and criteria in LIHI’s 2016 Handbook and then review the Project’s 2017 application materials posted 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 “Weybridge Project Comments” in the subject line, or by mail addressed to the Low Impact Hydropower Institute, 329 Massachusetts Ave, Suite 2, Lexington, MA 02420. The 60 day public comment period begins on October 26, 2017. Comments must be received at the Institute on or before 5 pm Eastern time on December 26, 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.

December 16, 2016: The Weybridge Hydroelectric project has been granted an extension of the current certificate term. The new expiration date is November 6, 2017. See extension letter for explanation below.

November 29, 2012: The Weybridge Project has been certified as low impact for a five-year term, effective February 6, 2012 and expiring February 6, 2017.

April 6, 2012: Public comment period on application has closed.

February 6, 2012: Central Vermont Public Service (CVPS) has submitted an application for the certification of its Weybridge Hydroelectric Project. Public comment period on application has opened.


2017-2019 Recertification

2012 Certification