Des Moines Water Works to customers: We need your help to keep water safe

The Des Moines Water Works announced today that it is continuing to use all available measures to provide residents safe drinking water after levels of nitrate in the Des Moines and Raccoon Rivers recently set new records.

In addition, in a statement the utility asked residents to limit the use of water for irrigation headed into the Memorial Day weekend to help the city temporarily avoid drawing water from the Des Moines and Raccoon Rivers:

Due to the recent historic nitrate concentrations found in the Raccoon and Des Moines Rivers, Des Moines Water Works is not currently pulling water from either river. The utility is able to meet current demand by relying on other water sources, including Maffitt Reservoir, Crystal lake and aquifer storage wells. If demand increases, Des Moines Water Works will have no choice but to start taking water from the heavily polluted rivers, and may be unable to remove nitrate in a manner that keeps up with high demand.

Although recent record nitrate levels at the Water Works have drawn attention in Iowa and nationwide, recent records are merely a new peak on an upward trend for pollution levels over the last 30 years, according to Water Works data.

Bill Stowe, head of the Des Moines Water Works, has previously attributed the trend to increasing runoff from agricultural land upstream.

Data from the Des Moines Water Works shows that over nearly 30 years, the concentration of nitrate in the Raccoon and Des Moines Rivers has been rising. Because this chart ends at 2010, the recent record nitrate event is not shown.

Data from the Des Moines Water Works shows that over nearly 30 years, the raw amount of nitrate in the Raccoon and Des Moines Rivers has also risen.