RRHP work progressing downstream; still on hold upstream due to high water levels

Jul 02, 2019

RRHP work progressing downstream; still on hold upstream due to high water levels

Progress on the intake structure at Red Rock Hydroelectric Project (RRHP) remains on hold on the upstream side of the dam due to elevated water levels on Lake Red Rock.

Water levels were more than 756.6 feet above sea level as of June 28. These levels need to drop to about 748 feet before upstream work can resume. The U.S. Army Corps of Engineers (USACE) estimates that the 748-foot level could be reached July 8.

Work is progressing on the downstream side of the dam. Final equipment installation, verification, and equipment checks are in full swing and the switchyard located between the dam and the powerhouse is nearly complete.

The underground transmission cable from the powerhouse to the overhead transmission line has been installed and final testing will start July 8. The transmission line is expected to be energized the first week of August.

Lake Red Rock is a reservoir on the Des Moines River. It was built for flood control 50 years ago. A celebration of this milestone will be held during the 2019 Lake Red Rock Balloon Fest July 12-14.

The USACE monitors, maintains, and determines water flow exiting the Red Rock Dam into the Des Moines River in accordance with its water control manual. Even with the addition of the hydroelectric project, the primary purpose of Lake Red Rock will remain flood control.

When RRHP becomes operational, currently scheduled for 2020 barring additional flood events, the USACE Hydrology Department will continue to be responsible for scheduling water releases from the Dam into the river as it has been for the past 50 years. These releases could be directed through the existing gates on the Dam, through the new hydroelectric facility, or through a combination of these depending on the reservoir elevation and desired flow release. Regardless of where the releases are directed, no additional water will flow into the river below the dam than what has occurred in the past.

RRHP is owned by the Western Minnesota Municipal Power Agency and will be operated by Missouri River Energy Services (

The Federal Energy Regulatory Commission license for RRHP allows for the generation of 36.4 megawatts of electricity. The current design model indicates that, to achieve this level of generation, it would take up to 10,000 cubic feet per second (cfs) of water flow. The minimum flow for the hydroelectric facility would be 1,200 cfs. When flows drop below this minimum level, the turbines will not operate efficiently so the hydroelectric facility will be taken out of operation.

Once fully operational, RRHP will be able to generate enough power to satisfy the electrical needs for all the homes in Marion County.

For more information about the Red Rock Hydroelectric Project, visit the project website at or contact Joni Livingston at Missouri River Energy Services, phone 605-261-3637 or email: