by Swaesy, Caleb, Sam and Haley

The tests they conduct include:

1- Chemical: the concentrations of dissolved nutrients (like nitrates and phosphates) indicate how toxic the water is to humans as well as to aquatic life.

2- Biological: the amount and kinds of life in a body of water are good indicators of the quality of that water. For example, mayflies prefer to live in water that is clean, and certain species of worms thrive in water that is polluted.

3- Physical: characteristics like transparency and temperature are affected by and can affect nutrient concentrations and aquatic diversity.

The DNR continues to value volunteer water monitoring for its role in increasing citizen awareness, knowledge, and stewardship of Iowa’s water resources, and appreciates all volunteers that help us achieve our natural resource conservation and enhancement goals. Volunteer water monitoring is best able to inform local water quality goals if the decision-making and coordination is locally-led. With the help of the DNR to get started, interested communities, watersheds, counties, and regions have an opportunity to take ownership and derive more value from their locally-led volunteer water monitoring programs.


A volunteer “citizen science” program within the Iowa Department of Natural Resources (DNR) that trains volunteers in monitoring the water quality of creeks, rivers, wetlands, and lakes, through chemical, physical, and biological tests.


According to the US Environmental Agency (EPA), they “build community awareness of pollution problems, help identify and restore problem sites, become advocates for their watersheds and increase the amount of needed water quality information available on our waters.”

“In September of 2009, I was conducting my monthly water sampling at Squaw Creek and I discovered large amounts of E. coli bacteria,” Erv said. “I notified the city of Ames and they began a search to find the source, leading them to a broken sewer line discharging raw sewage into Squaw Creek. The city had to dig up the street to correct the problem.

“I developed a moral interest in protecting our habitat. IOWATER allows me to gather scientific data that is used to assess the level of pollution in our watersheds and identify problems at a local level. Anything we do to improve our water quality at the local watershed level helps to correct a national problem.”

IOWATER Volunteer
Ames, IA

Under the Clean Water Act of 1972, water pollution control facilities in the U.S. are required to have an NPDES permit in order to discharge water to waterways.

by Jay, Moe and Zoey

NPDES permits regulate how much flow can be discharged to a receiving stream and set limits on pollutants such as biochemical oxygen demand, total suspended solids, and ammonia nitrogen.The Ames facility [shown here] was issued a permit by the Iowa Department of National Resources (DNR), with approval from the EPA. It is allowed to discharge 21 million gallons per day (MGD) but averages 6.

[Shown in this picture: wastewater with ammonia and organic matter is pumped into the top of a TRICKLING FILTER. It passes through a plastic matrix composed of corrugated plastic sheets and hollow cylinders lined with biofilm. These microbes reduce the biochemical oxygen demand and ammonia before it is discharged into the Skunk River.

National Pollutant Discharge Elimination System (NPDES)

A provision of the Clean Water Act that regulates point sources that discharge pollutants into US waters.


A source of pollution that discharges from a specific, confined site.


Pre-settled wastewater continuously sprayed over a fixed-bed, biological reactor operating under (mostly) aerobic conditions. As water migrates through the filter’s pores, organics are aerobically degraded by the biofilm covering the filter material, then discharged into a stream or waterway.

the Des Moines Water Works Chem Lab monitorS and manageS nitrate and phosphorous levels to ensure its safety for 500,000 people in the Greater Des moines area.

by Moe and Zoey

“I have the responsibility to assure customers that the data is accurate, defensible, and handled properly by trained personnel.”

Senior Chemist
Des Moines Waterworks
Des Moines, IA


The Environmental Protection Agency (EPA) has established National Primary Drinking Water Regulations (NPDWRs) that set mandatory water quality standards for drinking water by establishing “maximum contaminant levels” for contaminants that present a risk to human health. The MCL for nitrate is 10 mg/L or 10 parts per million.


A federal law established to set standards for the quality of drinking water in the U.S. It focuses on all waters actually or potentially designed for drinking use, whether from above ground or underground sources.

Des Moines Water Works has one of the world’s largest nitrate removal facilities, capable of removing nitrate from 10 million gallons of water every day.

by Dawson, Justin and Timothy

Nitrate concentrations in the Raccoon and Des Moines Rivers present Des Moines Water Works with their biggest water quality problem. When nitrate exceeds the Environmental Protection Agency’s (EPA) maximum contaminant level (MCL) of 10 milligrams per liter (mg/L), water must be purified using a nitrate removal facility which cost over $4 million to build. In 2015 alone, their plant had to operate for 177 days to bring DMWW into compliance with federal statutes defined by the Safe Drinking Water Act.


As nitrate-laden water passes through removal vessels filled with a sodium chloride-coated resin material is in each removal vessel, nitrate ions are captured and chloride ions are released into the water in a process known as ion exchange. This process is similar to a home water softener that removes calcium and magnesium ions from the water, exchanging them for sodium ions.

When the resin in these removal vessels is exhausted, it is regenerated with sodium chloride brine. Nitrate on the resin is exchanged for chloride, a reversal of the removal process. The spent brine containing the collected nitrate is diluted with partly-treated water and discharged back into the Raccoon River. DMWW has two National Pollutant Discharge Elimination System (NPDES) permits allowing for this nitrate discharge.