Iowa Institute of Hydraulic Research (IIHR) ‐ Hydroscience and Engineering Work Plan
Issue
New scientific tools and techniques and an improved understanding of the physical, chemical and biological processes are needed to predict nutrient mobilization, fate and transport in Iowa’s waterways. It also is important to improve scientific understanding of best management practices (BMP) at scales ranging from individuals to watersheds
Objective
Five research projects focus on developing scientific and technological tools to aid in the implementation of the Iowa Nutrient Reduction Strategy. A science and process-based framework using an integrated watershed approach will provide improved understanding of the complex nutrient management issues in Iowa, and the basis for possible solutions.
Approach
The first project will quantify the benefits of BMPs and land management practices, and associated hydrology on nutrient loading to water resources using hydrodynamic modeling tools. Three new models will be implemented to quantify nitrogen removal benefits over a range of precipitation and stream flow. The second project will quantify the benefits of BMPs and land management practices, and associated hydrology on sediment and phosphorus loading to water resources using hydrodynamic modeling tools. The third project will explore optimal placement of BMPs and land management practices for reduction of nitrogen, sediment and phosphorus loading to water resources. Using the suite of numerical tools developed in the first two projects, researchers will identify combinations of physical setting and current land use that result in the most nutrient reduction compared to current conditions. The fourth project will develop a functional, web-based database of available nutrient data sets in Iowa to be used by the Iowa Nutrient Research Center and other researchers. The fifth project will involve measurement of field data parameters to support modeling. Scientists will conduct field monitoring of nitrogen, sediment and phosphorus inputs and outputs for select BMPs installed in priority watersheds.
Project Updates
Note: Project reports published on the INRC website are often revised from researchers' original reports to increase consistency.
March 2016
FINAL REPORT
One project under this umbrella title is complete. The project studied floodplain phosphorus distribution in an agricultural watershed, and its role in contributing to in-stream phosphorus load. Over three years, researchers collected and analyzed soil samples from the floodplains, streambed and banks of the Turkey River to estimate the total phosphorus concentration in soils at each location. Key findings: Phosphorus concentration in floodplain soils is closely related to soil fine particle content; topography and flood characteristics control distribution of soil fine particle content and phosphorus concentration; lower floodplain terraces are short-term phosphorus storage locations, while upper floodplain terraces provide long-term phosphorus storage; dense root systems on floodplain sediments reduce erosion and total-phosphorus loss.
December 2015
Four projects are underway. Modeling tools are being used in the Upper Roberts Creek watershed to study the potential impacts on watershed nitrogen loads if there was widespread use of cover crops, and nitrate removal wetlands were constructed. In another project, researchers are analyzing soil samples to estimate the total phosphorus concentration in soils at the floodplains, streambed and banks of the Turkey River. This is helping to identify where the greatest amount of erosion is occurring. In the third project, the Iowa Water Quality Information System online tool is available at http://iwqis.iowawis.org. It offers access to real time nutrient data with a range of water-related information such as precipitation, stream flow and soil moisture. Improvements to the system are ongoing. The IIHR network of 26 water quality stations was fully deployed for the 2015 water season. Planning has begun to add an additional 15 water quality monitoring stations for the 2016 water season. Coverage then will include all of Iowa’s major rivers.
September 2015
Several projects are underway. One is using modeling tools to determine the impact on the Upper Roberts Creek watershed if there was widespread use of cover crops and other stacked nutrient management practices. In another project, researchers are analyzing soil samples to estimate the total phosphorus concentration in soils at the floodplains, streambed and banks of the Turkey River. Development continues on a web-based interactive database for the Iowa Nutrient Research Center. The online tool is running and improvements are being made. The IIHR network of 26 water quality stations was fully deployed for the 2015 water season. Of these, 21 were in the same locations as the 2014 sampling season, with five in new locations. Additional sensors that target Water Quality Initiatives have been proposed.
June 2015
Several projects are underway in support of ongoing modeling efforts. A total of 165 extracted soil cores from the Turkey River watershed field sites have been analyzed, which is about one-third of the soil samples taken. In this project, researchers are focused on estimating the total phosphorus concentration in soils at the floodplains, stream bed and banks of the Turkey River. Development has begun on the web-based interactive database for the Iowa Nutrient Research Center. Content so far includes nutrient data collected from various sources, and improvements to the system are in progress. The IIHR network of 26 water quality stations has been fully deployed for the 2015 water season. Of these, 21 are in the same locations as the 2014 sampling season, with five in new locations.
March 2015
A model for the Upper Roberts Creek watershed is nearing completion and the calibration process has begun. This model is being developed to quantify nitrogen removal benefits over a range of precipitation and stream flow. In the Turkey River watershed, researchers are focused on estimating the total phosphorus concentration in soils at the floodplains, streambed and banks of the Turkey River. Five field sites were selected and soil samples collected. Data is being analyzed to estimate the total phosphorus concentration in the Turkey River soils and develop maps with the average soil total phosphorus.
December 2014
Models are under development to quantify nitrogen removal benefits over a range of precipitation and stream flow. Model development continues in both Beaver Creek (Cedar River) and Roberts Creek (Turkey River). Work in Beaver Creek is focused on understanding the coupling of surface water and shallow groundwater processes and the integration of root zone nitrate concentrations. Model development in Roberts Creek is focused on calibration. Another project to quantify phosphorus concentrations in the Turkey River is underway, with researchers surveying cross-sections and analyzing soil cores.
September 2014
Three new models are under development to quantify nitrogen removal benefits over a range of precipitation and stream flow. The installation of real-time nitrate sensors in the Iowa River Basin is complete, and work on calculations between methods of various load calculations has progressed. Model development continues in both Beaver Creek (Cedar River) and Roberts Creek (Turkey River). Work in Beaver Creek is focused on understanding the coupling of surface water and shallow groundwater processes and the integration of root zone nitrate concentrations. Model development in Roberts Creek is focused on calibration. Another project to quantify phosphorus concentrations in the Turkey River is underway, with researchers surveying cross-sections and analyzing soil cores.
June 2014
Three new models are in development to quantify nitrogen removal benefits over a range of precipitation and stream flow. Real-time nitrate sensors were deployed in 2013 at 26 sites. In 2014, another three or four sensors will be installed. As the new models are developed, the real-time N data will be more useful than monthly grab-samples.
June 2014
Three new models are being developed to quantify nitrogen removal benefits over a range of precipitation and stream flow. The installation of real-time nitrate sensors in the Iowa River Basin began in 2013 and continued this spring. Work now is focused on developing high-resolution model inputs, and model calibration and validation. Model development continues in both Beaver Creek (Cedar River) and Roberts Creek (Turkey River). Current work in Beaver Creek is focused on understanding the coupling of surface water and shallow groundwater processes. Initial development of a course grid model for Roberts Creek has been completed, and the focus is on grid refinement and validation. Another project to quantify phosphorus concentrations in the Turkey River and Roberts Creek floodplains also is underway. Data have been assembled for land cover, land use, water quality and stream gauges.