Palo Alto Drainage District #15 North
In 2009 the Iowa Department of Agriculture invited all of Iowa’s 3000+ drainage districts to be part of a pilot program to demonstrate a market-driven approach that would improve both crop performance and achieve significant environmental benefits through combining updates to tile drainage infrastructure with targeted water quality wetland restorations. This integrated approach was designed to reduce surface runoff that can lead to phosphorous and other ag chemical runoff as well as address the higher nitrate levels associated with tile drainage.
While the improved drainage infrastructure provides many environmental benefits, there can be an increase in nitrate transport. However, by incorporating strategically targeted and sized wetlands below drainage district outlets, nitrate levels can be reduced by 40-70%. This complete system allows for improved crop production along with positive environmental benefits.
Multiple drainage districts responded to the solicitation for pilot projects, and ultimately a total of five projects from Clay, Palo Alto and Pocahontas Counties proceeded as pilots. All of these pilot projects faced challenges to their implementation, but none more so than Palo Alto Drainage District #15 North since it was responsible to build a mitigation wetland that would serve the needs of all five pilots. This project served as the lynch pin for all of the pilots by providing the means to demonstrate that water quality wetlands can provide mitigation, thereby making this market driven approach feasible for adoption across the rest of Iowa’s drainage districts that are nearing the end of their design life and will need to be modernized over the next few decades.
Over the past 5 years, the Palo Alto Board of Supervisors and landowners of Drainage District #15 North persevered to complete their project, which was finished in mid-2013. This project, along with the other pilot projects, will now provide for opportunities to validate the expected environmental and agronomic benefits of the combined systems approach and will provide invaluable information for future drainage districts to help them to also incorporate environmental benefits into their modernization efforts over time.
Q. What water quality practices were used?
A. Drainage improvements and a strategically targeted and sized wetland, of 29 acres, were placed in the 2,034 acre watershed. The wetland nitrate removal over a lifetime is 3,228 tons.
Q. Why were these practices voluntarily adopted?
A. This project is unique in that it improves drainage and provides water quality improvement. The drainage district outlets and wetland together can reduce nitrate levels by 40-70%. This complete system allows for improved crop production along with positive environmental benefits.
Q. What, if any, assistance (financial as well as technical) was received to employ these practices?
A. The Iowa Department of Agriculture and Land Stewardship invited all of Iowa’s 3000+ drainage districts to be a part of a pilot program in 2009. The Palo Alto Drainage District #15 received cost share of 50% from the department for this 5 year project. The total cost of the drainage improvements and the wetland was $4.5 million.