From time to time, I trade phone calls with an old acquaintance, Carl Palmquist. Carl served as a Commissioner of the Soil & Water Conservation District in Woodbury County (Iowa) during the time I worked for the Soil Conservation Service (now the NRCS).
Carl and I often lament the decline of two very important federal programs, the Flood Control Act of 1944 (PL-534) and the Watershed Protection and Flood Prevention Act of 1954 (PL-566). The Flood Control Act of 1944 authorizes the Secretary of Agriculture to install watershed improvement measures to reduce flood, sedimentation, and erosion damages. The Little Sioux Watershed, in Northwest Iowa, was one of 11 watersheds singled out for watershed planning and for installing measures to reduce runoff and erosion. The Little Sioux Watershed still stands as one of the granddaddies of all small watershed projects.
It is from these early watershed protection efforts that conservationists first learned that reducing flooding, and managing water was all about changing the hydrology on a small watershed scale. They learned that better soil infiltration and stair-stepping water down through the watershed, using flood control structures like ponds and wetlands, were the first essential steps. Unfortunately, due to lack of funding, these USDA watershed programs have been reduced to a skeleton of what they use to be. It seems like these effective approaches had been shelved for newer, in-vogue schemes.
The good news though, is that there is a renewed interest in using the watershed approach to reduce runoff and change hydrology across the landscape. The Iowa Watershed Approach (IWA), funded by the U.S. Department of Housing and Urban Development, is a new five-year project focused on addressing factors associated with flood disasters in the state of Iowa. The HUD Project, as it is commonly referred, was awarded $96.9 million.
The Iowa Watershed Approach focuses on in-field and edge-of-field practices to both reduce flood potential and decrease nutrient concentration in surface water. The practices include:
|Wetland Construction||Farm Ponds|
|Storm Water Detention Basins||Terraces|
|Sediment Detention Basins||Floodplain Restoration|
|Channel Bank Stabilization||Buffer Strips|
|Saturated Buffers||Perennial Cover|
The Iowa Watershed Approach promises to build on the lessons of the Flood Control Act of 1944 (PL-534) and the Watershed Protection and Flood Prevention Act of 1954 (PL-566), but adding in new practices and new approaches to reduce nutrient concentrations in surface water. It is good to see that ponds are back in vogue. And yes, it is about the hydrology…
Some content on the Iowa Watershed Approach originally appeared on the Iowa Learning Farms website by Adam Wilke, ISU Extension and Outreach Water Specialist.