LIHI Certificate #200 - Monroe Drop Project, Oregon

Project Name Monroe Drop
LIHI Certificate No.
LIHI Certificate Term
February 9, 2023 – February 8, 2033
Owner Natel Energy
State Oregon
Location North Unit Irrigation District Main Canal
Installed Capacity 0.3 MW
Average Annual Generation 1,078 MWh
Facility Type Run of canal (operates only if there is sufficient flow in the canal)
FERC No. P-14430. Conduit exemption issued August 1, 2014

The Monroe Drop project is located within the Deschutes River Basin on the U.S. Bureau of Reclamation’s (USBR) North Unit Irrigation District Main Canal (NUMC) near the Town of Culver, in Jefferson County, OR. The NUMC and the Monroe Drop structure are irrigation facilities operated by the North Unit Irrigation District (NUID) with a primary purpose to deliver irrigation water to nearly 50,000 acres of farmland in Jefferson County. Construction of the North Unit Irrigation project began in 1938 and was completed in 1949.

Water for the irrigation project comes from both the Deschutes and Crooked rivers. Water travels out of Wickiup Reservoir into the Deschutes River, and water from the Crooked river travels to a pumping plant where it is diverted to the NUMC in Bend, Oregon. From there, the water reaches users via the North Unit Irrigation District’s 65 miles of main canal and 235 miles of laterals.
The Main Canal’s Monroe Drop structure consists of a 35-­foot­-long, 15­-foot­-high concrete open irrigation drop with concrete winged transition sections upstream and downstream. Water falls between 13.5 feet to 16.5 feet at this structure, depending on the flow. The drop structure contains an automated gate that controls the normal flow of irrigation water through the Main Canal.

The hydro facility was constructed in 2015 and consists of a 12-foot-wide by 61.5-foot-long concrete intake channel, a 63-foot-long, 84-inch-diameter penstock, a 25-foot-long by 44-foot-wide powerhouse containing a single turbine/generating unit, an approximately 50-foot-long rectangular-section draft tube with inlet dimensions of 43 inches wide by 54 inches tall extends from the powerhouse to the bottom of the canal, and a 2,200­foot­long power line buried in conduit under the canal service road that interconnects with a 12.5-kV distribution line owned and operated by PacifiCorp.

An Obermeyer gate in the main canal spillway controls the head at the site and remains fully inflated during the irrigation season. The gate is lowered during canal weed flushing periods to allow for all canal debris to pass without causing blockages in the facilities. The gate is part of the canal operating system, not part of the hydro project.

The original 250-kW SLH turbine was replaced with a 300 kW Natel MS­D190 Fish-Safe Pit Style Restoration Hydro Turbine (RHT) in 2020. The RHT is a compact hydroelectric turbine that couples high performance with safe through­-turbine fish passage. Its unique fish­safe blades are thickened and optimized for low head applications, eliminating the need for fine fish screens which reduces cost while increasing plant efficiency.

The project operates in a “run-of-canal” mode generating electricity from available water flowing through the drop structure during the irrigation season only (April through October). During emergency powerhouse outages, flow that would normally pass through the powerhouse remains in the canal. The Obermeyer gate automatically adjusts to maintain constant elevation upstream of the drop structure and to maintain flow downstream of it, and typically remains fully inflated during the irrigation season. Project operations do not impact the timing or location of water delivered to irrigation users. After the irrigation season, the canal is drained.

The canal system is not a natural river system and as a human-made structure, is not supportive of aquatic life. Oregon Integrated Report’s online mapping tool indicates that the Crooked River upstream of the diversion is impaired for fish and aquatic life due to temperature, biocriteria, phosphorus, and total dissolved gas. The Deschutes River at the Main Canal diversion is impaired for temperature and pH. Since the Project is located 6 miles upstream of Haystack Reservoir with 55­60 similar drops of varying height along the canal system in that section, it is unlikely that the project would have any effect on dissolved oxygen levels. Given the short distance between the project intake and discharge and lack of storage, water temperature is also unlikely to be affected by Project operations.

The Deschutes and Crooked Rivers in the project vicinity are not host to any migratory fish species. Further, the canal is dewatered from November to March or April, so no year-round fish habitat exists. The intake at the Main Canal diversion dam on the Deschutes River, located 37 miles upstream from Monroe Drop, is equipped with a trash rack and fish screening, although it does not meet current state standards. Oregon Department of Fish and Wildlife (ODFW) reports that resident fish including redband trout, brown trout, and mountain whitefish have been observed stranded in the dewatered canal downstream of the Main Canal intake; and kokanee salmon have been observed in Haystack Reservoir which is located 6 miles downstream in the canal from the project. During the irrigation season, any fish moving downstream from the canal intake could therefore continue moving downstream through the project but as noted above, could be stranded downstream during canal dewatering, or be unable to spawn if they reached Haystack Reservoir. NUID reports that they, in coordination with the Deschutes Basin Board of Control, the Deschutes River Conservancy, and volunteers have rescued fish from the canal at the time of dewatering in the fall. However, Natel’s Restoration Hydro Turbine has been shown to provide safe fish passage in laboratory and field testing. In tests at Natal’s test facility, survival of silver phase American eels was 100% with minimal injury or impact even when the turbine was operated at full power. Field testing at the Freedom Falls Project (LIHI #178) found 48-hour survival of juvenile alewife to be 100%. The turbine design is an innovative technology, due in part to the thickness of the blades’ leading edges which were engineered to reduce tip speed and minimize strike probability and harm to fish.

The project itself does not adversely affect downstream fish passage or fish protection. Furthermore, there is nothing the project owner could reasonably do to influence NUID’s actions or schedule for implementing the long-proposed fish screens but with the influx of new funding it is likely that screening will be installed over the next few years. NUID is currently assessing funding mechanisms under the Infrastructure Investment and Jobs Act as well as awards from ODFW to implement updated fish screening.

The project lands consist of roughly 2 acres of federal lands in the Crooked River National Grassland managed with the Ochoco National Forest (0.89 acres for the powerhouse and 1.2 acres for the transmission line). The Grassland (administered by the US Forest Service) is managed for ranch land, fish and wildlife, recreation, mineral extraction, and fuelwood, with no direct impacts on the project. Lands west of the canal are primarily agricultural, and to the east is the Crooked River National Grasslands. As a conduit project, no impacts on shoreline or the watershed occur from project operations. No lands of ecological value and no critical habitats for threatened or endangered species exist in the project area. Consultation with ODFW and USFWS determined that no threatened or endangered species exist in the project area.

The Monroe Drop structure and canal are historic properties eligible for listing on the National Register of Historic Places. In 2013, the Oregon State Historic Preservation Office (SHPO) determined that project installation would have an adverse impact on the eligible historic properties. Thus, the project owner worked with the SHPO to mitigate these impacts. The subsequent replacement of the turbine was determined to have no impact on the historic properties.

There are no recreational resources or uses at the Project. NUID prohibits public access to the Main Canal due to safety concerns. However, other recreational resources are available in the vicinity, including at Haystack Reservoir which is popular for fishing, camping, boating, and day use as well as within the Crooked River National Grassland.

Compliance Status

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

2024: No material changes or compliance issues were identified. The project remains in compliance based on the annual review.

2023: Annual reporting for the current Certificate has not yet taken effect.

Certification History

June 8, 2023: The Low Impact Hydropower Institute has issued a final decision on the certification of the Monroe Drop Hydroelectric Project. The certification term is February 9, 2023 for a 10-year term which will expire on February 8, 2033.

May 8, 2023: The Low Impact Hydropower Institute has preliminarily approved Low Impact Certification for the Monroe Drop Hydroelectric Project. The full application and reviewer’s report are available below. 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 “Monroe Drop 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 June 7, 2023. If no appeal requests are received the certification terms will be February 9, 2023 through February 8, 2033.

April 10, 2023: Upon stakeholder request, the comment period for Monroe Drop has been extended one week. The comment period will close on April 17, 2023.

February 9, 2023: The Low Impact Hydropower Institute has received a complete application for Low Impact Certification of the Monroe Drop Hydroelectric Project.  LIHI is seeking public comment on this application.  Specifically, we are interested in knowing whether you think the Project meets the LIHI Low Impact Certification Criteria, as revised in the 2nd Edition Handbook.  Please review the program and criteria in LIHI’s revised Handbook and then review the Project’s application materials 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 “Monroe Drop 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 April 10, 2023 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.

Certification Files

Key Documents