Quantifying Nutrient Load Reduction Practices at Multiple Field Sites

Issue

Staff from the Iowa Geological Survey (IGS) will conduct three concurrent projects on behalf of the Iowa Nutrient Research Center that are focused on quantifying nutrient load reductions at multiple field sites in Iowa.

Objective

1) One project will continue field monitoring of a new "saturated waterway" conservation practice at the Clark Porter farm located near Reinbeck, Iowa. 

2) In a second project, a stacked conservation practice system will be constructed and monitored at the Mike Paustian farm near Walcott, Iowa.

3) In a third project, IGS services will be provided to assist other INRC researchers. 

Approach

1) The new waterway practice utilizes a multi-chamber control box and a series of Agri Drain Water Gates to back tile water upslope into waterway sediments for nitrate reduction. Tile flow and water level and quality measurements will be made to monitor the performance and functionality of the new saturated waterway system and quantify the water flux and nitrate load reductions occurring in the waterway.

2) A new saturated buffer will be installed at the outlet of a tile system with surface inlets to document the future potential of stacking Modified Blind Inlets (MBIs) and saturated buffers together. Following installation, sediment and phosphorus (P) loads delivered to the saturated buffer with surface inlets will be measured and the performance of the saturated buffer will be assessed. Baseline data collection will be used to evaluate how stacking MBIs within a tiled catchment can be integrated into a saturated buffer design.

3) IGS services will help measure, map and monitor deep soil and groundwater conditions at project sites, including drilling and well installation services, geophysical mapping, water level monitoring and data analyses.

Results from the projects will be shared on social media, in the IGS Geode publication, at local, regional and national conferences, and in scientific publications.