LIHI Certificate #73 - Siphon Power Project, Oregon

Project Name Siphon Power
LIHI Certificate No. 73
LIHI Certificate Term
October 28, 2020 – October 27, 2030
Owner Central Oregon Irrigation District
State Oregon
Location Located at river mile 170.9 on the Deschutes River, Oregon.
Installed Capacity 5.5 MW
Average Annual Generation 22,470 MWh
Facility Type diversion/run-of-river
FERC No. P-3571 issued in 1987, expires 08/31/2037

The Siphon Power Project is located on the Deschutes River in the City of Bend, Deschutes County, Oregon. There is no dam associated with the project. There are seven dams on the Deschutes River downstream of the Project to the confluence with the Columbia River, including Pelton Round Butte (LIHI #25). The Wickiup Dam is the next dam located upstream of the project and impounds Wickiup Reservoir, the largest of the Cascade Lakes. There is also a diversion dam approximately 3.5 miles upstream of the Siphon Power diversion. The project diversion was originally constructed in 1903 and later modified into the current configuration in the mid 1970s. The hydropower facilities have been operating since 1989.

The project consists of the use of the pre-existing Central Oregon Irrigation District’s canal system including the Deschutes River diversion and the approximate two miles of water conveyance system downstream which delivers water to the project penstock and powerhouse. Immediately downstream of the diversion intake is the downstream fish louver array that guides and returns entrained fish back to the Deschutes River. Downstream of the fish protection facility, water enters the 10-foot-diameter double inverted siphon pipe. About 1,200 feet downstream of the start of the open canal, a buried 9-foot-diameter pipe is utilized to deliver excess water to the powerhouse. About a mile and a quarter downstream from the diversion structure, an underground powerhouse contains two turbines and generators with a combined capacity of 5.5 MW. From the penstock intake to the river downstream, there is a 135-foot drop available to drive the two turbines which discharge back to the Deschutes River.

The project operates in a run-of-river mode and provides a minimum flow of 400 cfs into the 1.5-mile-long bypass reach. This flow regime was developed in coordination with Oregon Department of Fish and Wildlife (ODFW) to protect fish resources in the Deschutes River. The project diverts 25% of stream flow, on average.

The water available for power generation depends on irrigation flow releases from upstream storage reservoirs during the irrigation season and typically the flow in the bypassed reach is much more than the minimum 400 cfs. During the non-irrigation season, flow available will range from none to the maximum generation capacity of about 640 cfs. Flows are electronically monitored, and streamflow is reported quarterly to resource agencies.

Waters within the project reach are designated as impaired upstream for flow modification, habitat modification, sedimentation, turbidity, and temperature. Downstream, the river is impaired for flow modification, temperature, and pH. Consultation with Oregon Department of Environmental Quality concluded that due to run-of-river operations and minimum bypass flows, the project does not adversely impact water quality of the river.

Project waters support coldwater fish species, primarily brown and rainbow trout, as well as a few warmwater species. Non-migratory species include mountain whitefish, several sculpin species, longnose and speckled dace, chiselmouth, and largescale and bridgelip sucker. Since no dam is associated with the project, it does not present a barrier to passage in the river. The minimum bypass flow facilitates downstream movement past the project and the louver array mitigates the potential for entrainment into the irrigation diversion.

The project lands consist of 22 acres. Vegetative buffers are present along the river shorelines, which consist of the ponderosa pine shrub type. Land use in the immediate project vicinity is mostly undeveloped although residential development and the City of Bend and its suburbs are located nearby. The project annually contributes to a Mitigation and Enhancement fund that ODFW facilitates, utilizing funds for river enhancement projects, riparian area regrowth, and even fish passage projects in the Deschutes basin.

Threatened or endangered species potentially present in the project vicinity include the gray wolf, yellow-billed cuckoo, Oregon spotted frog, steelhead trout, and bull trout. Eight irrigation districts (including the project owner) in the Deschutes Basin of Oregon and the City of Prineville, Oregon prepared a Deschutes Basin Habitat Conservation Plan. The plan represents a collaborative effort between irrigators, resource agencies, non-governmental agencies, and the Confederated Tribes of the Warm Springs Reservation to protect the habitat of steelhead trout, bull trout, sockeye salmon, and the Oregon spotted frog and to mitigate the effects of the eight irrigation districts and the City of Prineville on over 480 miles of rivers and creeks.

The project area does not support any cultural or historic resources listed on the National Register of Historic Places. Consultation with the State Historic Preservation Office concluded that the project does not adversely impact any cultural or historic resources in the project vicinity.

Recreational resources at the project include a walking trail from the Pilot Butte Canal to the project powerhouse which connects to several other trails in the area. Whitewater boating is not recommended in the project area due to hazardous, life-threatening rapids. Public access is provided free of charge.

Compliance Status

There are no facility-specific conditions in the current Certificate.

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

2022: No material changes or compliance issues were identified. The project remains in compliance based on the annual review.

2021: There were no reported changes or compliance issues. The project remains in compliance based on the annual review.

2020: 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.

June 23, 2021: The Low Impact Hydropower Institute has issued a final decision on the recertification of the Siphon Power Hydroelectric Project. The 30-day appeal window closed on June 16, 2021 and no appeals were filed. Therefore, the decision to recertify the project is now final. The new term for the project is October 28, 2020 through October 27, 2025.

May 18, 2021: The Low Impact Hydropower Institute (LIHI) has preliminarily approved the Siphon Power (LIHI #73) for a new 5-year term 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 “Siphon Power Project” in the subject line, or by mail addressed to the Low Impact Hydropower Institute, 1167 Massachusetts Ave, Office 407, 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 June 17, 2021. The full application and reviewer’s report are available below. If no appeal requests are received and the decision becomes final, the Certification term for the Project will be October 28, 2020 through October 27, 2025.

March 2, 2021: The Low Impact Hydropower Institute (LIHI) has received a complete recertification application from Central Oregon Irrigation District for the Siphon Power Project located on the Deschutes River in Oregon. LIHI is seeking comment on this 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 “Siphon Power 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 at the Institute on or before 5 pm Eastern time on May 1, 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. The complete application can be found below.

April 20, 2016: LIHI Executive Director Michael J. Sale, using authority delegated from the LIHI Governing Board, has certified that the Siphon Power Hydroelectric Project (FERC No. P-3571) satisfies the LIHI Certification Criteria.  A Preliminary Decision was announced on March 4, 2016, and a 30-day appeal period was open through April 4, 2016. No requests for appeal were received. This Certification Decision includes two facility-specific conditions, as follows:

  • Satisfied 2021 Condition 1. As part of their annual Compliance statement to LIHI, the Owner shall include electronic copies of or electronic addresses to the reports that they file with the Oregon Department of Fish and Wildlife related to conservation flows and tailrace fish observations, covering the prior four quarters.
  • Satisfied 2021 Condition 2. The Owner shall notify LIHI within 30 days of any changes in the level of mitigation enhancement funding for fish and wildlife, with particular attention to changes at or around January 1, 2021.

The effective certification date for the Siphon Power Project is October 28, 2015 for a five (5) year term, which will expire on October 28, 2020.

November 2, 2015: The Low Impact Hydropower Institute has received a complete application for a new term of Low Impact Certification for the Siphon Power Hydroelectric project.  The application materials can be found in the Files section below.

June 19, 2015: The Siphon Power Hydroelectric project has been granted an extension of the current certificate term. The new expiration date is December 31, 2015. See Extension Letter_2015 Recert for explanation below.

May 28, 2011: The Siphon Power Hydroelectric Project has been certified as low impact for a five year term, effective October 28, 2010 and expiring October 28, 2015.

October 28, 2010: The Central Oregon Irrigation District has submitted an application for certification of the Siphon Power Project.

Certification Files

2020 Recertification

2015 Recertification

2010 Certification

Key Documents