Des Moines and Raccoon Rivers

Every year, Des Moines Water Works treats about 15 billion gallons of water from the Raccoon River and the shallow groundwater wells heavily influenced by it.

Water sourced from the Raccoon River is consumed by approximately 500,000 people, around 17 percent of Iowa’s population. In the Upper Midwest, Lake Michigan, the Mississippi River and the Missouri River supply water to more people from a surface water resource than the Raccoon River.

Now, ACWA reaches beyond the Raccoon River and Des Moines River watersheds — we have gone statewide!

Des Moines Headwaters
Acres: 790,000
Percent Row Crop: 78
Sample Sites: 0

West Fork Des Moines
Acres: 703,000
Percent Row Crop: 81
Sample Sites: 1
2011 Average Nitrate Concentration at Outlet: 5.6 mg/L

East Fork Des Moines
Acres: 843,000
Percent Row Crop: 86
Sample Sites: 1
2011 Average Nitrate Concentration at Outlet: 8.6 mg/L

Middle Des Moines
Acres: 1,091,000
Percent Row Crop: 76
Sample Sites: 27
2011 Average Nitrate Concentration at Outlet: 6.5 mg/L

Boone
Acres: 583,000
Percent Row Crop: 88
Sample Sites: 30
2011 Average Nitrate Concentration at Outlet: 9.0 mg/L

North Raccoon
Acres: 1,594,000
Percent Row Crop: 81
Sample Sites: 33
2011 Average Nitrate Concentration at Outlet: 7.2 mg/L

South Raccoon
Acres: 727,000
Percent Row Crop: 67
Sample Sites: 15
2011 Average Nitrate Concentration at Outlet: 5.9 mg/L

Real-time Nitrate Monitoring In The Raccoon River

ACWA has played a key role with the partners below in establishing real-time nitrate monitoring in the Raccoon River.

In 2006, ACWA purchased the first real-time monitoring device in the Raccoon River Watershed for $10,000. The IDNR and DMWW contributed operational and maintenance support. The USGS provided a site near Van Meter, just below the confluence of the North, Middle and South Raccoon branches.

Thanks to this installation, the City of Panora now has advance information about upstream nitrate levels and can manage its water quality accordingly. ACWA and the following partners provided funding to support real-time monitoring at the Panora site:

  • Lake Panorama Association
  • City of Panora
  • Des Moines Water Works
  • The Izaak Walton League
  • Raccoon River Watershed Association

Based on success of the Van Meter and Panora real-time monitoring devices, USGS has funded installation, operation and maintenance of two nitrate monitors for the North Raccoon River at Sac City and Jefferson.

Mississippi River and other locations

Based on the ACWA success at these sites, the University of Iowa located 10 real-time monitoring units on the Mississippi River and USGS has plans for 27 more throughout Iowa.

The benefits of real-time nitrate monitors include:

  • An accurate assessment of Raccoon River nitrate levels when grab sampling is not conducted (during the winter months)
  • A mechanism to estimate relative nitrate loads from the South and North Raccoon watersheds
  • An estimate of the relative nitrate loads in tile water versus runoff water
  • Advance information for DMWW about upstream nitrate levels
  • A visible demonstration to the public and regulators of the commitment to monitoring and characterization of water quality
  • A mechanism to establish working relationships with public agencies, including the U.S. Geological Survey (USGS), county governments, and the Iowa Department of Natural Resources (IDNR)