Iowa water sensors show 2016 uptick in nitrates

LA PORTE CITY — If the doctor says you’ve got to lose weight for your health, you need to step on the scale once in a while, right?

Iowa is among states trying to reduce the amount of nitrates washing from farm fields into streams and rivers, where they can harm human health and are adding to the creation of an oxygen-deprived dead zone near the mouth of the Mississippi River in the Gulf of Mexico.

Iowa has more than 70 sensors deployed this year on streams and rivers across the state that measure nitrate loads and concentration so observers can tell whether water treatment plant upgrades, wetland improvements and agricultural conservation practices are working to reduce pollution.