Nitrate levels up in Iowa rivers, but Cedar Rapids drinking water safe

Rivers in Iowa are experiencing high nitrate levels, though the city of Cedar Rapids does not anticipate that high nitrate levels will impact the city's drinking water supply.

Levels must reach 10 milligrams per liter to prompt a health advisory, and the city has not had to issue such an advisory in the past. It does not expect to now either, Megan Murphy, communications director and education coordinator for the city's Utilities Department, said Tuesday.

Murphy noted that the city of Cedar Rapids does not draw its drinking water directly from a river, and so is better protected from high nitrate levels than cities like Des Moines, which gets its water from a river. Cedar Rapids draws water from shallow wells along the river.

The city of Des Moines, she said, began operating its nitrate removal facility last Friday for the first time since 2007. The city of Cedar Rapids has not needed such a facility.

Murphy said nitrate levels were measured at 18.5 milligrams per liter in the Cedar River at Blairs Ferry Road, which she termed one of the highest levels ever recorded in the Cedar River.

Nitrate levels in Iowa rivers, she said, typically rise during rainy periods in the spring as nitrogen fertilizer that has been applied to farm fields washes into streams and rivers.

"We do not expect to exceed the limit, but we saw this moment as an opportunity to start talking … about nitrates and how the quality of our source water is connected to the quality of our drinking water," Murphy said.