Iowans across the state asked to conserve water due to dry wells, high nitrate levels

Iowans in communities around the state, primarily in central and southern regions, have been told to refrain from watering their lawns, washing their cars and filling swimming pools. 

Some utilities issued preventative conservation orders in anticipation of dry conditions through the summer, while communities in central Iowa are conserving water to keep drinking water nitrate concentrations below the federal level. For other Iowans, water conservation orders are the new normal. 

Conservation for protection from nitrate contamination

Central Iowa Water Works, which serves more than 600,000 people in the Des Moines region, issued its first ever lawn watering ban June 12 due to high nitrate concentrations in the Des Moines and Raccoon rivers from which it sources. 

Nitrate levels in the Des Moines and Raccoon rivers have tested as high as 17 mg/L this month, making it difficult for the facilities to meet water demands while removing enough nitrates to comply with federal drinking water standards. 

The U.S. Environmental Protection Agency set a maximum nitrate concentration of 10 mg per liter to avoid pregnancy complications, blue-baby syndrome and other potential health risks. Facilities in the central Iowa system have been able to keep concentrations below the federal limit in outgoing water by “pulling all the levers” on its nitrate removal facilities.

Melissa Walker, a spokesperson with Des Moines Water Works, said the concentrations Monday were 15.6 mg/L in Des Moines River and 15.3 mg/L in Raccoon River. 

“When concentrations are this high, production at treatment facilities is limited,” Walker said in an email. “The lawn watering ban will remain in effect until nitrate concentrations drop in our rivers.” 

In a Tuesday press conference, CIWW leadership said the lawn watering ban has been effective at reducing demand on the system.

The City of Des Moines has additionally closed spraygrounds and splash pads to help conserve water. CIWW customers can be penalized if caught violating the orders. 

Des Moines Water Works, part of CIWW, installed a nitrate removal facility in the 1990s due to steady increases of nitrate concentrations in its source-waters. A fact sheet from the facility said operation of the removal system adds an estimated $10,000 each day to facility costs. The removal system has been operating this spring for nearly 60 days, according to a release from CIWW. 

The “spring flush,” as water quality advocates call it, of nitrates in Iowa rivers is an annual occurrence caused by spring rains that wash nutrients off of crop land, feedlots and other areas, into the waterways. 

Heather Wilson, Midwest Save Our Streams coordinator with Izaak Walton League of America, said surface water nitrate concentrations across the state “habitually” exceed the 10 parts per million standard in May and June. 

“For the average surface water readings to be so high is definitely indicative of a lot of input,” Wilson said. “Some of it is cyclical, like every year around this time there’s more rain, so there’s more runoff, but as far as what that runoff contains, it’s definitely being impacted by the fertilizer and manure applications on the landscape.” 

Izaak Walton League leads the Nitrate Watch program, which relies on citizen scientists to take regular samples of rivers, creeks and drinking water. The data is available online and shows streams and wells with records of high nitrate concentrations. 

Wilson said it’s important to note that 10 parts per million is the regulatory standard that water treatment facilities are held to, but research exists that shows concentrations of 5 parts per million, which is equivalent to milligrams per liter, may be linked to increased risk for certain types of cancer and thyroid diseases. 

Wilson said EPA has initiated processes to reevaluate the regulatory figure, though the work has been started and stopped with administrative changes. 

“Ten parts per million, that’s the regulatory standard, and that’s the goal for Waterworks, because that’s what they’re held to, but I think it’s important to remember the research that exists about what is actually probably a healthier nitrate diet,” Wilson said.

Ted Corrigan with Des Moines Water Works said Tuesday the water coming out of the Fleur Drive facility had nitrate concentrations of 7.7 mg/L.

The Nitrate Watch map shows quite a few red and orange dots, indicative of excessive nitrate concentrations, around the Des Moines region, but also around Iowa City, Waterloo and several other parts of the state. 

Nitrate monitoring from the Iowa Water Quality Information Center, which pulls from U.S. Geological Survey monitors, show surface level measurements in the Iowa River in excess of 10 parts per million this spring. 

Jonathan Durst, the water superintendent for the City of Iowa City, said while the city’s water treatment facility draws from the Iowa River, it also draws from groundwater aquifers to dilute nitrate concentrations and comply with EPA regulations. 

Durst said the Iowa River nitrates spikes periodically, but if it were to stay consistently high, the facility’s current dilution methods at the plant would not be effective. 

Durst said it’s “hard to put a finger on” if the levels have gotten worse or changed over the past years.

“It really is weather and human dependent, like where is the rain going to hit and how much fertilizer has been spread on the ground,” Durst said.  

Low wells in southwest Iowa make water conservation a perennial necessity

Water conservation orders have become the normal for cities in southwestern Iowa, where years of drought conditions have created water shortages in the system. 

The shortages have become severe enough that several towns were put under boil advisories for almost a month, after too much stress on the system depleted stores in city water towers, causing a drop in system pressure. 

Municipalities on the Regional Water Rural Water Association in southwest Iowa no longer have to boil their drinking water, but remain in a “red” level advisory that restricts things like lawn watering, filling pools and washing cars. 

These shortages are not caused by nitrate filtration concerns, but by consistent drought over the past 10 years that has impacted the replenishment of groundwater stores.

In its latest release, Regional Water said it is 7-10 days away from completing a pipeline to pump water into the system from Council Bluffs’ water supply, which sources from the Missouri River.

Some Iowans in the water system, which covers Avoca, Persia, Panama, Portsmouth, Westphalia, Kirkman, Tennant, Earling, Exira, and Brayton, however, are skeptical the pipeline will solve the water shortage problems they have been dealing with for the past several years. 

Denison Municipal Utilities, together with West Central Iowa Rural Water Association have been under water use restrictions for watering lawns, filling pools and washing cars since mid March, due to “an extended dry spell” that has caused the levels at the facility to drop. 

Shenandoah residents have been under some form of water use restrictions for about a year and a half, according to the city’s water superintendent, Tim Martin. The municipality is currently under a stage four restriction that prohibits residents from irrigating lawns, filling pools, or watering with their outdoor hoses. 

“We’re hanging on but we’re not in dire straits yet,” Martin said. 

The utility has bought property over the Fremont Channel, an alluvial aquifer, and plans to install two new wells to tap into the groundwater source. Martin said he expects the project to be online in fall 2026 and said he was “very confident” the town “should not have to worry about drought again” once the wells are in place.

Utilities are not required to report water conservation orders to the Iowa Department of Natural Resources, but DNR field offices are generally aware of shortages in their regions. 

Field office staff in north central, northeast and northwest Iowa said they were not aware of any communities under water use restrictions. 

Staff at the field office in Des Moines, covering south central Iowa communities, said they were only aware of the restrictions in the Des Moines region. 

In southeast Iowa, the Poweshiek Water Association initiated mandatory water conservation orders at the beginning of March for Tama and Amana systems. The water association issued the same order last year, and according to its website, was able to keep enough water in the system through the high demand summer months until wells were replenished in August. 

The water association had to terminate some well contracts last year which, if completed, would have alleviated the need for a summer 2025 conservation order. The association said it is planning to drill new wells in Tama and Amana in July, and continue to treat existing wells to improve flow. 

In the meantime, affected customers in parts of Tama, Benton, Black Hawk, Poweshiek, Mahaska, Jasper, Iowa, and Keokuk counties join other Iowa residents in refraining from watering grass, washing cars or streets and filling swimming pools. 

“Let’s all band together and do our part one last time to help each other through this time frame,” a release from Poweshiek Water Association read.