The Stevens Mill Hydroelectric Project is located in Franklin, N.H. Franklin is in the Lakes Region of central New Hampshire. The Winnipesaukee River drains New Hampshire’s largest lake, Lake Winnipesaukee, and flows southwest 10.5 miles to join with the Pemigewasset River, forming the Merrimack River. The Project is 1.5 miles upstream of the confluence of the Winnipesaukee and the Pemigewasset rivers. The dam is the second one upstream of the confluence; the Franklin Falls Dam (LIHI Certificate #83) is located about one mile downstream of the Project. The Merrimack River flows south to Massachusetts where it turns northeastward to empty into the Atlantic Ocean at Newburyport.
|Project Name||Stevens Mill|
|LIHI Certificate Number||123|
|LIHI Effective and Expiration Dates||March 5, 2015
March 5, 2020
|Owner||Franklin Power, LLC, a subsidiary of Eagle Creek Renewable Energy, LLC|
|Location||Located at River Mile 1.5 on the Winnipesaukee River in New Hampshire.|
|Installed Capacity||Stevens Mill: 0.236 MW River Bend: 1.7 MW|
|Average Annual Generation||Stevens Mill: 1,182 MWh River Bend: 3,539 MWh|
The site was originally developed in the early 1900s by the M.T. Stevens Company, a manufacturer of woolen dress goods. The origins of the company can be traced to J.P. Stevens and Company, which was founded in 1813 in North Andover, Massachusetts by Captain Nathaniel Stevens and produced woolen broadcloth in 1813. In 1901, Moses T. Stevens incorporated the company, constructed the Stevens Mill Complex and associated hydroelectric facilities, and changed the company name to M.T. Stevens Company.
The Project utilizes two generating units located in separate powerhouses. Unit 1 (236 kW) is located on the north side of the river immediately across from the Stevens Mill Building No. 1 while Unit 2 (1,700 kW) is located approximately 900 feet southwest of the dam and adjacent to Stevens Mill Building No. 2. The two units comprise the Stevens Mill facility (Bow Street powerhouse) and the River Bend facility, respectively. Unit 1 is connected to the dam via a 150-foot penstock, and Unit 2 via a 740-foot penstock. Unit 1 is a Flygt turbine that was installed in 1985; it is used to maintain conservation flows in the reach of river bypassed by the River Bend station.
The Project dam is a concrete gravity structure approximately 80 feet long and 22 feet high. The crest elevation is reported as 312.55 feet NGVD; however, it is equipped with a 3-foot-high Obermeyer inflatable crest gate, which was installed in 2008 and provides an overflow elevation of 315.28 feet. With the pool maintained at approximately elevation 315 feet, the impoundment covers approximately one acre with an average depth of about seven feet. The Franklin Falls dam controls the tailwater elevation, about 281.5 feet NGVD, at the River Bend facility. The Project has an average annual production of 4,721,000 kWh (Stevens Mill: 1,182,000 kWh and River Bend: 3,539,000 kWh).
July 27, 2015: LIHI 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 Stevens Mill Hydroelectric Project (FERC No. 3760) satisfies the LIHI Certification Criteria. The effective certification date for the Stevens Mill Project is March 5, 2015 for a five (5) year term, which will expire on March 5, 2020, with the following conditions:
- Condition No. 1. The facility owner shall comply with Section 4.1 of the August 14, 2014, Memorandum of Agreement by implementing appropriately protective bypass conservation flows immediately upon approval by the U.S. Fish and Wildlife Service and the New Hampshire Department of Fish and Game. Since this certification is being granted without the minimum bypass flow having been deemed appropriately protective by the resource agencies, LIHI may withdraw certification if it determines that the facility owner is failing to make a good faith effort to cooperate with the resource agencies in determining a final minimum bypass flow. The owner shall provide LIHI with monthly status updates until this issue is resolved.
- Condition No. 2. The facility owner shall develop a system for producing and maintaining records sufficient to demonstrate compliance with the headpond elevation and flow management limitations for an instantaneous run-of-river operation and bypass conservation flows, including flows as necessary to operate fish passage measures. The facility owner shall comply with Section 4.2 of the August 14, 2014, Memorandum of Agreement. Within three months of the date of issuance of the certification, the facility owner shall provide LIHI with a copy of the operations and flow monitoring plan. Prior to filing the plan, the facility owner shall obtain plan approval from U.S. Fish and Wildlife Service and New Hampshire Department of Environmental Services; written confirmation of the approvals will be filed with the plan. The plan shall be updated as necessary to reflect any future changes in minimum bypass flows and flow releases for fish passage operation.
- Condition No. 3. Modified 2017: a) The facility owner shall continue to notify LIHI within 30 days if changes in the downstream fish passage are made. b) During the term of this certification, should a resource agency request implementation of upstream passage at the facility, the owner shall notify LIHI within 30 days and provide LIHI with a copy of the request and its response.
- Condition No. 4. To enable NHDES to make a determination of Project compliance with New Hampshire quantitative water quality standards, the facility owner shall complete water quality sampling during summer 2015 following a study plan approved by NHDES. By December 31, 2015, the facility owner shall provide LIHI with a letter from NHDES documenting NHDES’s review and conclusions. If NHDES determines that structural or operational changes are necessary to meet water quality standards, the facility owner will provide LIHI with a proposed implementation schedule at the same time it files the NHDES letter.
- Condition No. 5. Modified 2017: The facility Owner shall report in its annual compliance statement, whether or not any changes or amendments were made in the MOA. If changes were made, the facility owner will provide a brief summary of those changes. The MOA shall be extended, by mutual agreement, in accordance with Section 1.1 of the MOA to keep it in effect throughout the term of the LIHI certification of this facility. Under the unlikely scenario of the US Fish and Wildlife Service having no interest in extending the MOA, the facility owner shall continue to operate Stevens Mill in accordance with the most recent version of the Plans required by the MOA.
March 11, 2015: On March 5, 2015, the Low Impact Hydropower Institute (LIHI) received a complete application from Eagle Creek Renewable Energy for the Low Impact Certification of the Stevens Mill Project, FERC P-3760-007, located on the Winnipesauki River in New Hampshire.
- Stevens Mill_Certification Effective_03052015
- Stevens Mill-River Bend Project LIHI Application Questionnaire
- Stevens Mill-River Bend Project LIHI Application – Appendices
- Stevens Mill Fish Passage MOA – 2014
- Appendix F.1 – Stevens Mill Project Bounday and recreational access Map
- Appendix I.6_19980820_ Order Amending Exemption 3760
- New Hampshire Fish & Game Letter 2014-08-27
- Appendix A.3_NHDES commitment