Officials say nitrate levels are still high in central Iowa waterways that supply the Des Moines area with drinking water.
It’s been nearly a week since the Central Iowa Water Works banned its 600,000 customers from watering lawns to keep drinking water from violating EPA standards.
Water usage has dropped, but Ted Corrigan, CEO at Des Moines Water Works, says the ban will remain in place.
“We’re going to need your continued support,” Corrigan says. “This is likely going to be measured in weeks, not days.”
Nitrate levels in the Des Moines and Raccoon rivers are at their highest since 2013. Corrigan says the main source of the high nitrate levels is fertilizer from farm field runoff.
Christina Murphy, general manager at West Des Moines Water Works, says treatment plants are working at max capacity to filter out the chemicals, but she notes, central Iowans are using less water.
“We estimate that there’s a 30% reduction in water that’s being consumed by our customers,” Murphy says, “obviously attributable to outdoor water use.”
Murphy says the ban will continue in order to keep nitrates in drinking water below the federal standard. She says water works staff are not worried about additional restrictions.
Central Iowa Water Works is also planning multiple long-term projects to expand treatment capacity.
(By Lucia Cheng, Iowa Public Radio)