Local efforts respond to high nitrate levels

In August, 600 Iowans gathered at Drake University, concerned about high nitrate levels in their water. Following a two-year study for Polk County, 16 scientists reported on the health of the Des Moines and Raccoon Rivers, the sources of much of the water used in central Iowa. They found the rivers had one of the highest nitrate levels in the nation, often exceeding the EPA's 1992 limit of 10 milligrams per liter, with 80% of the contamination attributed to agricultural sources. Nitrates above 10 mg/L are considered hazardous to pregnant women and newborns.

Central Iowa Water Works (CIWW) processes river water to keep nitrates below the EPA standard. Heavy rain raised levels beyond the limit, leading to a summer lawn watering ban. The ban allowed CIWW time to lower nitrate levels, meeting the region's essential water needs. To prepare for the future, it will invest $344 million in system upgrades, despite already having the world's largest nitrate removal system.

Professor Jerald Schnoor from the University of Iowa suggested rising cancer rates in Iowa could warrant lowering the allowable nitrate level, emphasizing that "the current standard is somewhat outdated," citing health concerns at levels as low as 3 to 5 mg/L.

To minimize lawn watering bans, the Urbandale Water Utility plans to build an aquifer storage and recovery well. Urbandale will purchase treated water from CIWW when demand is low and store it for use in peak usage times. Neil Weiss, General Manager for Urbandale Water, hopes this will enhance distribution reliability and drought resilience.

Local businesses are also affected by the nitrate issue. Aaron Graff from Culligan Home Water reported an increase in reverse osmosis systems since the water ban was implemented. Graff noted, "Reverse Osmosis reduces nitrates in residential water by as much as 80%." Conversely, sales for A+ Lawn and Landscape's irrigation systems have fallen by over 50%. Specialist Ethan Dykstra recommends adding Wi-Fi smart controllers and rain sensors to irrigation systems to reduce water usage by up to 40%.

Urbandale residents Bruce and Anne Hoffmaster have adopted a natural approach, replacing their lawn with pollinator plants and native species that require less water. They collect rainwater in barrels and have never needed to water their lawn. Bruce stated, "Our goal is to work with nature, not against it."

Reducing nitrates in Iowa's water is a challenging task. Despite growing concerns, Iowa plans to reduce the number of nitrate monitoring stations from 80 to 20. In August, the federal government removed the Des Moines and Raccoon Rivers from the list of impaired waterways, thereby eliminating funding for cleanup. Elliot Anderson, a scientist on the Polk County water report, said, "This is a step in the wrong direction, but there are many steps we can take" to make water safe.

Wayne Bruns is an Urbandale resident and a volunteer with Sustainable Urbandale. This article was previously published in Urbandale Living: https://www.iowalivingmagazines.com/urbandale-archives