The Red Rock Hydroelectric Plant near Pella, Iowa, was commissioned late last year adding a new hydroelectric power-generating facility to an existing flood control dam that previously had no generation capacity. This six-year, $400-million retrofit the existing dam provides power for up 18,000 homes in the area.
Originally a flood control dam on the Des Moines River and Lake Red Rock near Pella, Red Rock was built by the U.S. Army Corps of Engineers in 1969. The USACE still owns and operates the flood control portion of the dam, but the Western Minnesota Municipal Power Agency sold the bonds necessary to make the investment to add the powerhouse and make it the second-largest hydroelectric power-generating facility in Iowa. It’s operated by Missouri River Energy Services, a utility that has a power supply agreement that entitles MRES to the output of all WMMPA-owned facilities. MRES has 61 member municipal electric systems in Iowa, Minnesota, North Dakota and South Dakota. Stantec was the owner’s engineer and designer-of-record.