LIHI Certificate #132 – Dog River Project, Vermont

The Dog River Project is located on the Dog River in Northfield, Vermont, in the Nantanna Mill complex. The Dog River is formed by the hydrology of the Green Mountains and flows into the Winooski River which culminates in Lake Champlain. There are three partially breached dams downstream and two partially breached dams upstream of the project.

The project includes a concrete dam, intake structure, penstock, air blast system, two turbines, an earthen channel tailrace, and a plunge pool.

The dam is a reinforced concrete ogee-shaped arch structure with a total length of approximately 90 feet, including a 78-foot-long spillway. The dam is approximately 22 feet high. The remaining portion of the dam is made up of non-overflow abutments and an intake structure. The intake includes trashracks with 2-inch clear spacing. Flow then moves through a 7-foot-diameter, approximately 40-foot-long steel penstock with 25 feet of gross head. An air blast system works automatically to maintain clean racks and low intake water velocities.

The project has two identical vertical Kaplan turbines which were installed in 1996 and have a total installed capacity of 0.222 MW. The operations of the units depend on available flows in the river. When flows are sufficient, both units operate simultaneously.

The tailrace is an unlined earthen channel approximately 120 feet long. The bypass reach is approximately 190 feet long, and includes a short plunge pool and shallow ledge section. A permanent notch cut in the flashboards provides the required minimum flow to the bypass. To provide for water control, there is an adjustable gate, which can slide vertically to modify the opening. Generally, the gate is operated to provide approximately four inches of water depth. The notch and adjustable gate are located immediately to the right of the intake structure.

Project Name Dog River
LIHI Certificate No. 132
LIHI Certificate Term October 14, 2016 - October 14, 2021, extended to April 14, 2022
Owner Gravity Renewables
State Vermont
Location Dog River, river mile 11.8, Northfield, VT
Installed Capacity 222 kW
Average Annual Generation 650 MWh
Facility Type Run of River
FERC No. P-6757, exempt 1984

The project operates in a run-of-river mode and impounds a 1.5-acre reservoir. The project is required by FERC and the Vermont Department of Environmental Conservation (VDEC) to provide 5 cfs continuous minimum flow. However, the project voluntarily provides 20 cfs to the bypass section below the dam through a permanent notch in the flashboards. This minimum flow helps to maintain adequate dissolved oxygen levels and to protect aquatic habitat at the base of the dam.

Waters within the project reach are designated Class B and the Dog River is not listed on Vermont’s list of impaired streams and rivers. Consultation with VDEC confirms that there are no water quality concerns associated with the project.

No anadromous or catadromous fish species are present in the river now or historically as confirmed by consultation with VDEC. Additionally, downstream passage is blocked by Northfield Falls, a natural barrier, and the partially breached Cross Brothers Dam. The Dog River is an important wild trout fishery supporting brook, brown, and rainbow trout populations. The trashracks have 2-inch clear spacing which mitigate the potential for entrainment of most fish.

The project property consists of 2 acres. There are no lands of significant ecological value in the project area. Based on review with USFWS, VT Natural Heritage Inventory, and VT Fish and Wildlife Department, no state or federally listed threatened or endangered species exist in the project vicinity.

No cultural or historical resources are present in the project area based on past licensing studies.

Natural obstructions and safety concerns limit access to the project. Additionally, the adjacent Nantana Mill limits access to the area. Fishing is a common recreational use in the Dog River.

Certification History

March 30, 2017:  On February 6, 2017, LIHI Executive Director Shannon Ames announced a Preliminary Certification Decision that the Dog River Hydroelectric Project (FERC No. P-6757) satisfies the LIHI Certification Criteria.  The Dog River certification includes the following conditions:

  • Condition 1. During the term of LIHI certification, a minimum flow of 20 cfs, or inflow if less, shall be maintained in the bypass reach at all times, as such flows formed the basis of VT DEC’s position that healthy flows for fish, wildlife and water quality are being released. Deviations from this flow requirement shall be reported to VT DEC and summarized annually in the annual compliance letter to LIHI. If deviations occur, the owner shall explain the causes, the frequency and magnitude of them, the resulting environmental effects, and plans to avoid these deviations in the future.
  • Partially Satisfied Condition 2. By no later than October 31, 2017, the Owner shall supply operating records related to downstream flows from October 1, 2016, to September 30, 2017, to the Vermont Agency of Natural Resources, Department of Environmental Conservation (VT DEC). The parties shall evaluate operations to ensure run-of river operations are reliably maintained. By December 31, 2017, the Owner shall report to LIHI on the findings made by VT DEC relative to this data, along with any facility changes that may be found necessary to ensure continuing compliance.

As provided for in Section 4.2.5 of the LIHI 2nd Edition Handbook, notice of the preliminary decision to certify was posted on the Institute’s website and sent to the stakeholder email distribution list on February 7, 2017. A 30-day period was provided to anyone who commented on the original application to request an appeal, and no requests for appeal were received.

The Dog River Project is now deemed certified by LIHI for a five (5) year term. The effective certification date for the Dog River Project is October 14, 2016, expiring on October 14, 2021.

February 6, 2017: On February 3, 2017 LIHI issued a Preliminary Certification Decision that the Dog River Hydroelectric Project (FERC No. P-6757) satisfies the LIHI Certification Criteria.

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 which begins on February 7, 2017 and ends on March 7, 2017.  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.

If no appeal is requested within the 30-day period, the Executive Director will issue LIHI Certification for the facility and post a notification of certification on the Institute’s website.  Once final, the effective certification date for the Dog River Project is October 14, 2016 for a five (5) year term, which will expire on October 14, 2021.

January 6, 2017: LIHI has received a comment letter from the Vermont Department of Environmental Conservation in regards to the Dog River application for LIHI certification. The letter can be found in the Files section below.

January 3, 2017: LIHI has received a comment letter from the MadDog Chapter of Vermont Trout Unlimmited (MDTU) in regards to the Dog River application for LIHI certification. The letter can be found in the Files section below.

November 7, 2016: On October 14, 2016, the Low Impact Hydropower Institute (LIHI) received a complete application from Stuwe and Davenport Partnership Partnership, LLC, a wholly-owned subsidiary of Gravity Renewables, Inc. (Gravity),  for the Low Impact Certification of the Dog River hydroelectric project, located in Northfield, VT (FERC P-6757).

LIHI is seeking public comment on this application. Specifically, we are interested in knowing whether you think the Dog River project meets the LIHI Low Impact Certification Criteria. The Dog River application is subject to review using the Criteria in the LIHI Certification Handbook of 2014.  Please review the program and criteria in LIHI’s 2014 Handbook and then review the Project’s 2016 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 with “Dog River Project Comments” in the subject line, or by mail addressed to the Low Impact Hydropower Institute, PO Box 194, Harrington Park, New Jersey 07640. The 60 day public comment period begins on November 7, 2016.  Comments must be received at the Institute on or before 5 pm Eastern time on January 6, 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.

The Dog River comment period has been extended to January 8, 2017.