Drainage District No. 15
Iowa | Agriculture
ISG innovated tile drainage infrastructure solutions to create a model for quality wetland restorations.
An Iowa Department of Agriculture pilot program provided the opportunity to design wetland mitigation that could be translated across the state.
Palo Alto County volunteered to be part of this pilot project with the Iowa Department of Agriculture to demonstrate a market driven approach that would improve both production and achieve significant environmental benefits through combining updates to tile drainage infrastructure with targeted water quality wetland restorations. This integrated approach was designed by ISG to reduce surface runoff that can lead to phosphorous and other agricultural chemical runoff as well as address the higher nitrate levels associated with tile drainage. Drainage improvements and a strategically located and sized wetland were placed in the watershed.
As one of five pilot projects of the Iowa Wetland Landscape Systems Initiative, this ISG designed project included construction of 0.70 miles of open ditch; 6.7 miles of tile; design and construction of a nutrient removal wetland encompassing 42.7 acres; 404 permitting with channel mitigation plan; and development and coordination with the Natural Resource Conservation Service (NRCS) for mitigation of farmed wetlands. This project provided the means to demonstrate that wetlands can provide mitigation, thereby making this market driven approach feasible for application 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.