LIHI Certificate #66 - Orono Project, Maine

Project Name Orono
LIHI Certificate No. 66
LIHI Certificate Term June 1, 2020 – May 31, 2030 (option to extend to May 31, 2033)
Owner Black Bear Hydro Partners, LLC, a subsidiary of Brookfield Renewable Energy Group
State Maine
Location Located at river mile 0.0 on the Stillwater Branch of the Penobscot River in Orono, Maine.
Installed Capacity 6.548 MW

Powerhouse A: 2.798 MW

Powerhouse B: 3.75 MW

Average Annual Generation 33,731 MWh

Powerhouse A: 14,413 MWh

Powerhouse B: 19,318 MWh

Facility Type Run-of-river
FERC No. P-2710 issued in 2005, expires 03/31/2048

The Orono Project is located on the Stillwater Branch of the Penobscot River in Orono, Penobscot County, Maine. The site was first developed for hydropower in 1898, and in the ensuing decades went in and out of operation. The project stopped operating in 1996 due to catastrophic failure of the facility’s wood-stave penstocks which caused the project to be shut down. After FERC issued a new license for the project in 2005, the facility was refurbished and began commercial operation of the four units in the original powerhouse in 2009.

The Penobscot River basin is New England’s second largest river system with a drainage area of 8,570 square miles. The basin includes the East and West Branches of the Penobscot River, Piscataquis River, Sebec River, Pleasant River, Mattawamkeag River, Passadumkeag River, the Stillwater Branch of the Penobscot River and the mainstem of the Penobscot River. The project is located just upstream of the Stillwater Branch’s confluence with the mainstem. The Stillwater Project (LIHI #67) is located one mile upstream. With removal of the Veazie Dam in November 2013, there are no longer any dams on the Penobscot River downstream of the Orono Project. Removal of the Veazie and Great Works dams was a key feature of the nationally recognized restoration of the Penobscot River.

The Orono project is included in the Penobscot River Restoration Agreement. The overall intent of the agreement is to provide enhancements to the Penobscot River’s environmental resources, and lower and minimize the influence of the owner’s hydroelectric projects on those resources while maintaining renewable hydropower generation from the river. The restoration effort was one of the largest river restoration projects in our nation’s history. In an unprecedented collaboration, a diverse group of stakeholders worked together to restore 11 species of sea-run fish to the Penobscot River, while maintaining energy production.

The project consists of a 1,178-foot-long by 15-foot-high concrete gravity dam with a 320-foot-long spillway topped with 2.4-foot-high flashboards; three 10-foot-diameter penstocks; a 40-foot-wide, 94-foot-long and 27-foot-high surge tank; and an original powerhouse with four existing generating units. The second powerhouse was constructed in 2012-2013 and began operation on November 22, 2013.

The new powerhouse (Powerhouse B) is located within the existing bypassed reach about 420 feet downstream of the dam and is supplied by a 292-foot-long, 25-foot-wide, 12-foot-high concrete penstock and surge chamber just upstream of the powerhouse. A new 84-foot-wide, 20- foot-high intake is integrated into the existing intake and shares a single trashrack with 1-inch clear spacing. The powerhouse contains seven turbine generators, 4 Francis turbines, 2 vertical propeller type, and 1 Kaplan. Combined installed capacity is 6.548 MW.

The project operates in a run-of-river mode and impounds a 180-acre reservoir. Impoundment fluctuations are limited to one foot and the project provides a minimum flow of 200 cfs. 153 cfs is provided through the fish passage facility and 47 cfs via the spillway. The upstream eel passage facility adds an additional 1-2 cfs to this flow from June 1 – August 31. This flow regime was developed in consultation with Maine Department of Environmental Protection (MDEP).

Waters within the project reach are designated as Class B, suitable for fish propagation and survival, as well as primary contact recreation. The Stillwater Branch of the Penobscot is not listed as impaired though the mainstem of the Penobscot River at Orono is classified as a Category 4B water due to E. coli presence. This categorization is not influenced or caused by project operations.

Diadromous species present in the Penobscot River include alewife, Atlantic salmon, American shad, sea lamprey and American eel. Historically, the Penobscot River supported larger runs of American shad, blueback herring, Atlantic sturgeon, shortnose sturgeon, rainbow smelt, tomcod, and striped bass. The project has an upstream fish lift and trapping facility. Trapped fish are trucked to a location upstream on the mainstem. This is because it was determined to be more beneficial for overall fish restoration of the river basin to concentrate the upstream passage in the Penobscot River mainstem. A permanent, flow-through concrete upstream eel passage channel was installed in 2016, located to the right and downstream side of the non-overflow spillway section of the dam. It is approximately 4 feet wide and 49 feet long, has a bristle-brush floor, and ends approximately 20 feet from the pier between the spillway and the overflow dam. A 1.5-cfs conveyance flow is provided at the upstream eel passage seasonally.

The downstream fish passage facility consists of an opening in the flashboards on the spillway used for 2 weeks during the downstream Atlantic salmon smolt migration, and an 8-foot-wide entrance into a 20-foot-long by 12-foot-wide floor screen chamber with a 3-foot wide exit at the downstream end that is operated throughout the fish migration season. A lower level entrance for American eel, consisting of a 4-foot square opening at the base of the trashrack, which outlets to the downstream end of the screen chamber, is also part of the downstream fish passage facility. An attraction flow of up to 150 cfs is provided to the downstream surface bypass that discharges into a plunge pool below the dam. The surface bypass is opened for the duration of the juvenile alosine outmigration period.

The project lands are limited to those occupied by project facilities (dam, powerhouses, and penstocks). No critical habitats for endangered or threatened species or lands of significant ecological value exist in the project area due to the limited land ownership.

Threatened or endangered species potentially present in the project vicinity include Atlantic salmon, shortnose and Atlantic sturgeon, yellow lampmussel, Northern long-eared bat, little brown bat, eastern small-footed bat, big brown bat, red bat, hoary bat, silver-haired bat, tri-colored bat, hyssop-leaved fleabane, and wood turtle. Ongoing efforts to restore river connectivity for the listed aquatic species have yet to confirm the effectiveness of the fish passage facilities at the project. The facilities are not likely to adversely impact these species, but effectiveness of passage is still under review. The mussel species is not expected to be impacted by normal run-of-river operations. Similarly, the bat and turtle species are not likely to be impacted as limited shoreline management activities occur. The project has committed to adhering to the USFWS 4(d) rule concerning bat roosting site protection should any construction or tree-cutting occur at the site. Consultation with the Maine Natural Areas Program (MNAP) identified the presence of the hyssop-leaved fleabane, a state Species of Special Concern, in the project area. The species has been previously observed in the area and led to the development of a sensitive plant protection plan. The plan has helped to preserve critical habitat for the species and MNAP has stated it has no concerns related to project impacts on the species.

Consultation with the Maine Historic Preservation Commission has concluded that no historic, archaeological, or cultural resources exist in the project area. The State Historic Preservation Office and Tribal Historic Preservation Office must be consulted should any potential resources be discovered in the area.

Recreational resources at the project include a canoe take-out, portage trail around the dam, and put-in location, and whitewater canoeing and kayaking opportunities. Additionally, Webster Park, the University of Maine’s Stillwater Branch Riverside Recreation Area, and the Fay Hyland Botanical Garden and Walking Trail provide access to the project impoundment. Public access is provided free of charge.

Compliance Status

The Certificate includes the following facility-specific conditions:

Condition 1: The facility Owner shall provide LIHI a copy of agency correspondence documenting numerical performance standards that the agencies may establish for upstream eel passage and/or downstream diadromous species for the Penobscot River basin that affect the Stillwater Project within 60 days of publication of the standards.

Condition 2: In annual compliance statements, the facility Owner shall notify LIHI of actions implemented, as agreed to by agencies and PIN, that address upstream passage concerns:

a)    If additional upstream fish passage studies are required at this Project, the plan and schedule for implementation, study results, and agency and PIN comments on them shall be provided to LIHI in applicable compliance statements. Should studies occur, LIHI reserves the right to modify this condition based on study results and assessment of the effectiveness of upstream passage.
b)    If additional meetings with agencies and PIN are convened to discuss fish lift modifications or provision of upstream passage measures at the Project, the facility Owner shall provide a summary of the meetings, agency and PIN recommendations, areas of disagreement if any, and plans and schedules for implementing facility upstream passage modifications. Should modifications occur, LIHI reserves the right to modify this condition in light of future Project changes.

Condition 3: In annual compliance statements, the facility Owner shall notify LIHI of actions implemented, as agreed to by agencies and PIN, that address downstream passage concerns for alosines and American eel:

a)   At the conclusion of meetings held to address the three concerns identified in FERC’s March 6, 2020 letter, the facility Owner shall provide a summary of the final agreements. This shall include a copy of filing(s) made to FERC addressing these concerns, plans and schedules for implementation, results of studies, and agency and PIN comments on them. Should the Owner not agree to make all requested modifications, the rationale for these decisions shall be provided.
b)   Should studies or modifications occur, LIHI reserves the right to modify this condition based on study results and assessment of the effectiveness of downstream passage.

Condition 4: In annual compliance statements, the facility Owner shall notify LIHI of actions implemented, as agreed to by agencies and PIN, that address Atlantic salmon downstream passage concerns:

a)   Any changes made in the current Atlantic salmon downstream passage performance standards established by the Biological Opinion or if formal consultation under the Endangered Species Act ahead of the 2023 deadline is needed. The status of actions undertaken as part of any formal consultation shall also be provided.
b)   If during the term of LIHI certification, the current or new performance standards cannot be met within the existing or any new timeframes established by NMFS, LIHI reserves the right to modify, suspend, or revoke the Certificate.
c)   If, prior to expiration of the LIHI Certificate, the facility Owner receives NMFS concurrence that current or revised numerical performance standards for downstream Atlantic salmon have been met, thus confirming safe and effective downstream passage, the facility Owner may request that LIHI consider possible certification extension pursuant to satisfying the PLUS requirements under the Threatened and Endangered Species Criterion.

2023: No material changes or compliance issues were identified.  The project remains in compliance based on the annual review.  For Conditions 1, 3 and 4 the project reported no changes.  For Condition 2, the project submitted the 2022 upstream eel passage report.

2022: No material changes or compliance issues were identified.  The project remains in compliance based on the annual review.  For Conditions 1 and 4 the project reported no changes.  For Condition 2, the project submitted a 2021 river herring upstream passage telemetry study report and a plan to conduct an upstream juvenile eel PIT tag efficiency study in 2022.  For Condition 3, the project submitted results of the 2016 downstream eel passage study reanalysis.

2021: Annual reporting for the current Certificate has not yet taken effect.

Certification History

January 1, 2022: The LIHI Certificate term has been extended in accordance with Revision 2.05 of the LIHI 2nd Edition Certification Handbook issued January 1, 2022. Refer to the facility table above for the new term.

April 26, 2021: The decision to recertify the Orono Project became final after the close of the appeals period on April 17, 2021 with no valid appeals filed. The Certification term is from June 1, 2020 through May 31, 2025.

March 18, 2021: The Low Impact Hydropower Institute (LIHI) has preliminarily approved recertification of the Orono Project for a new 5-year terms of Low Impact Certification. 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 “Orono 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 April 17, 2021. The full application and reviewer’s report is available below. If no appeal requests are received and the decision becomes final, the Certification term for the Project will be June 1, 2020 through May 31, 2025.

December 1, 2020: The Low Impact Hydropower Institute has received a complete application for Low Impact recertification of the Orono Project. The complete application can be found below. LIHI is seeking public comment on the application. 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 “Orono 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 January 30, 2021 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.

March 24, 2017: On March 13, 2017, LIHI issued a Preliminary Certification Decision that the Orono Hydroelectric Project (FERC No. 2710) continues to satisfy the LIHI Certification Criteria. The Orono certification includes the following conditions:

  • Condition satisfied 2018. Condition 1. The Owner shall notify LIHI within 30 days of receipt of USFWS certification of the upstream and downstream anadromous fish and eel passage facilities as required by the Lower Penobscot River Multiparty Settlement Agreement. This certification requires affirmation that: a) the facilities were designed and installed as prescribed, b) the facilities are ready for routine operation as evidenced by approved Operating Manuals and electronic data collection systems, and c) one year of testing and any required “fine tuning” has been completed. It is assumed that certification of the fish lift indicates that the capacity concerns have been resolved. If such USFWS certification is not received by the end of 2017, the Owner shall provide LIHI documentation as to why the certification has not been received and the plan and schedule to remedy deficiencies identified by USFWS preventing such certification.
  • Condition 2. If the requirement for re-initiation of quantitative studies of downstream passage of juvenile and adult alosine species occurs within this LIHI certification period, the Owner shall notify LIHI within 60 days of receipt of such study re-initiation. This notification shall include the study schedule including the expected report issuance date. A copy of the final report, along with agency statement as to whether the testing results prove that safe downstream passage has been demonstrated, shall be provided to LIHI within 60 days of issuance of the final report.
  • Condition 3. The Owner shall notify LIHI within 60 days of receipt of USFWS, NMFS and MDMR acknowledgement that the standards specified in the Biological Opinion for safe downstream passage of Atlantic salmon have been met. Currently, effectiveness testing could be completed by 2018 based on the three-year testing requirement, unless advancement to a higher enhancement sequence is found to be necessary. Should this occur, the Owner shall notify LIHI in the annual compliance report as to the new date by which such continuing testing to meet passage standards is expected to be completed.
  • Condition 4. The Owner shall provide LIHI with a summary of the results of the 2016 quantitative downstream effectiveness study for American eel, along with any comments received from USFWS, NMFS and Maine Department of Marine Resources (MDMR) as to whether the testing results prove that safe downstream passage for American eel has been demonstrated. Also, the Owner shall provide a summary of the annual American eel upstream passage results, along with confirmation that any changes to the passage facilities recommended by the resource agencies have been, or are scheduled for implementation. The noted upstream and downstream passage results shall be provided within 60 days of report finalization.
  • Condition satisfied 2018. Condition 5. The Owner shall provide LIHI a summary of the results the 2017 survey for Hyssopleaved fleabane, a state-listed species of Special Concern, as required by the Sensitive Species Protection Plan. This summary shall be provided within 60 days of its finalization, following review and comment by the Maine Natural Areas Program and New England Wild Flower Society.

This application was processed under the 2014 edition of the LIHI Handbook because the application materials were received prior to 2016. As provided for in Section 2.14 of the LIHI 2014 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.  The appeal request must state specific reasons why the hydropower facility should have failed one or more criteria.  If an individual or organization did not comment on the initial Application Package, they may not file an appeal.  Further information about the LIHI appeal process is available in the LIHI Handbook, available HERE. 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 Orono Project is June 1, 2015 for a five (5) year term, which will expire on June 1, 2020.

December 11, 2015: The Low Impact Hydropower Institute has received a complete application for a new term of Low Impact Certification for the Orono Hydroelectric project.  The application materials can be found in the Files section below.

The public comment period for this application closed on February 12, 2016.

January 28, 2011: The Orono Hydroelectric Project has been certified as low impact for a five year term, effective June 1, 2010 and expiring June 1, 2015.

August 2, 2010: Public comment period for the application for certification has been closed.

June 2, 2010: Black Bear Hydro Partners has submitted an application for certification of the Orono Hydroelectric Project. Public comment period on the application will be open for 60 days.

Certification Files

2020 Recertification

2015 Recertification

2010 Certification

Key Documents