If you’ve seen the news in Central Iowa, you’ve heard about the nitrate levels in the Des Moines and Raccoon rivers and the treatment challenges it’s creating for Central Iowa Water Works. This is a serious situation, but it’s not uncommon to observe nutrient spikes during a wet spring. 

There are several contributing factors — nonpoint source, water treatment capacity and weather — and addressing the issue requires a multipronged approach. Agriculture, conservation, recreation and urban and business growth can coexist in Iowa. 

Weather impacts

Nitrate levels are primarily driven by weather and stream flows, and we can’t control those variables. The sources of nitrates include farm activities, naturally occurring high organic soils, homes in town and in the country, businesses and industries. No one source or activity is the singular cause or solution. 

Iowa has experienced drought for the last several years. May and June are Iowa’s wettest months, and increased precipitation flushes built up nutrients from the soil and tile lines. 

These annual “flush” events cause nitrate levels to spike, then return to the baseline when precipitation and streamflows decrease. 

We know these events happen when we have a wet spring, and we are targeting conservation practices to minimize the impact. 

Nonpoint source contributions 

Iowa has nutrient-rich soils, and plants need nutrients to grow. Farmers apply nitrogen to support crop growth. 

Advances in precision agriculture empower farmers to be more efficient with nitrogen applications. Applying the right amount of nitrogen at the right time balances productivity and land stewardship. 

Managing inputs is important, but we also need conservation practices, like cover crops, wetlands and saturated buffers, to minimize soil erosion and filter nitrates from the runoff. Cities can also play a role and install urban conservation practices to manage stormwater and prevent sediment runoff from paved and residential areas. 

The Iowa Department of Agriculture and Land Stewardship works with farmers, ag groups and numerous other public and private partners to accelerate adoption of conservation practices. 

We’re proud of the Batch and Build project with Polk County, which streamlines the development process by working with multiple landowners and sites at once. It has yielded 155 new practices, and we’re getting ready to kick off phase three. 

We’re also partnering with the Great Outdoors Foundation on projects in Polk County and southwest Iowa. Together we’ve built a nutrient-reduction wetland and 47 structures to reduce stream erosion, with more projects planned. 

Public-private partnerships are essential to achieving our shared water quality goals. Thank you to the farmers and landowners who have said yes to conservation, and all the partners working alongside us. 

Criticizing is easy, but doing the boots-on-the-ground work is hard. Together we are making meaningful progress. 

Water treatment infrastructure 

Nonpoint source is one-half of the equation. We also need to invest in water treatment infrastructure. Since 2020, the Des Moines metro's population has increased by 6% and new businesses have arrived, which has increased water demands. We must closely examine the region’s investments in water treatment infrastructure and what it takes to meet future needs. 

The blame game is unproductive. There is work to be done on both sides of the point/nonpoint source equation. These investments are expensive, take time and require collaboration. 

Every Iowan has a role to play in improving water quality. Let’s work together to accelerate conservation and infrastructure up­­grades and continue attracting more residents, businesses and talent to Des Moines. 

Naig is Iowa's secretary of agriculture.