Des Moines River, Iowa - Improving flows and water levels for water quality and habitat
Located along the Des Moines River in Iowa, Saylorville Dam and Reservoir is located directly upstream from the City of Des Moines, and Lake Red Rock Dam and Reservoir is approximately 50 miles downstream. The Corps dams are operated for flood risk management as well as recreation, water supply, drought management, and fish and wildlife.
Altered flows to the river affect resident fish, mussels, and other wildlife that depend on the river’s aquatic, riparian, and floodplain habitats. The Corps and Conservancy collaborated with scientific and environmental experts to identify environmental flow requirements for the Des Moines River. Several practices have been adopted to manage the reservoirs in ways that provide a variety of benefits.
Lake Red Rock - Water flows through the radial gates at Lake Red Rock during high water. Reservoir outflows and impounded water in the pool influence fish, mussels, and other wildlife that depend on the river’s aquatic, riparian, and floodplain habitats (USACE photo).
Des Moines River below Lake Red Rock - A science-based process was used to define environmental flow targets for the Des Moines River. Water managers and reservoir operators are considering how to implement and incorporate those targets into operations (USACE photo).
Recreating in Lake Red Rock - Kayaker explores bluffs along the shoreline of Lake Red Rock, a reservoir located about 50 miles downstream of Des Moines, Iowa. Lake Red Rock is operated for flood risk management as well as recreation, water supply, and fish and wildlife (photo by Ron Huelse).
Water quality improvements - Aerial photo of Lake Red Rock delta. Reservoir delta areas can be managed as shallow wetlands, reducing nutrients, improving water quality, and providing habitat and forage for a variety of birds (USACE photo).
Reservoir habitat management - A bar-tailed godwit foraging on freshly exposed mudflats at Lake Red Rock. Water levels are adjusted in the lake to attract shorebirds during migration periods. Exposed mudflats are ideal habitat and provide foraging opportunities for shorebirds (photo by Stephen Dinsmore, ISU).
Floodplain restoration - A Natural Resource Specialist checks water levels at river oxbows below Saylorville Dam. Improvements to this 3,100 acre area will restore vital seasonal conditions for fish and amphibians in spring and for waterfowl in late summer and fall (USACE photo).
Construction and operation of the Saylorville and Red Rock dams serve public interests by providing flood risk management, water supply, and many other social benefits. Reservoir operations also alter patterns of river flows, thereby affecting floodplain hydrology and life cycles of aquatic dependent species. The flow regime of the Des Moines River has been altered by increased summer flows, lower spring flows, and reduced peak flows, which have substantially reduced floodplain inundation. Concurrently, river flows have been significantly altered by upstream land use and drainage modifications. Read More
- Des Moines Water Works
- Drake University
- Iowa Department of Ag & Land Stewardship
- Iowa Department of Natural Resources
- Iowa State University
- Natural Resources Conservation Service
- Ottumwa Water and Hydro
- Polk County Conservation
- Red Rock Lake Association
- The Nature Conservancy - Iowa Chapter
- University of Iowa
- U.S. Fish and Wildlife Service
- U.S. Geological Society
- William Penn University