The State of Iowa has wrapped up a statewide effort to identify and map six types of conservation practices (terraces, ponds, grassed waterways, water and sediment control basins, contour strip cropping, and contour buffer strips/prairie strips) and provide the most comprehensive inventory of conservation practices in the nation.
An analysis of the results shows the value of this public and private investment in conservation to be $6.2 billion. Additional analysis is underway to use the science of the Iowa Nutrient Reduction Strategy to quantify the water quality impact of these practices in terms of reduced sediment and phosphorus loads to Iowa streams.
Iowa is the first state to analyze every watershed within its borders using the LiDAR surveying method and aerial imagery to create a detailed assessment of conservation practice implementation. These data allow for a much more detailed and accurate analysis of soil conservation efforts focused on phosphorus reduction because it includes all practices implemented by farmers, including those conducted without government cost share.
The Iowa Department of Natural Resources and researchers at Iowa State University led the three-year effort to use LiDAR-derived elevation data and aerial imagery to identify and inventory the conservation practices present on the landscape. The inventory provides a benchmark for measuring progress.
Maps and additional information about the project can be found here.