Iowa farmers and many Iowa municipal utilities are working together to reduce the amount of nutrients in Iowa rivers, streams and groundwater that provide Iowans drinking water, farm and utilities officials said last week.

Farmers are reworking their traditional cropping patterns to add cover crops. They are refining fertilization programs to reduce the potential for nutrient loss. And they are adopting conservation tillage practices as they work to improve the quality of water leaving their fields.

At the same time, many Iowa municipalities are working with farmers to install bioreactors, wetlands and other permanent...