2024 - CORTEVA WETLAND PROJECT - JOHNSTON

Project Partners

• Polk County

• Great Outdoors Foundation

• Corteva

• Boone SWCD

• Polk SWCD

• Beaver Creek Watershed Management Authority
  

  
  

  
  

  
  

Grant award: $389,000 - WQI  

Total project: $858,000

Applicant/Partner Contributions: : $469,000

Description
Polk County has partnered with Corteva to construct three wetlands on their 1,100-acre campus in Johnston located along Beaver Creek. The project used three different wetland types (stormwater, floodplain, and enhanced oxbow wetland), floodplain habitat restoration and native landscaping to treat a mix of urban and agricultural drainage before flowing into Beaver Creek and the Des Moines River. The stormwater wetland captures and treats 20 acres of highly impervious runoff. The floodplain wetland diverts tile water for treatment before it reaches Beaver Creek. The large oxbow also manages road runoff and has a special outlet to manage the larger storm events. The project treats stormwater runoff from over 450 acres and provides education to many visitors on the benefits of a variety of constructed wetlands for water storage and treatment in the landscape.

The project was completed in October 2025.

Practices

• Native landscaping

• Oxbow restoration

• Stormwater wetlands