Reduction of solids and nutrient loss from agricultural land by tailwater recovery systems

Authors: OMER, AUSTIN - Mississippi State University; MIRANDA, LEANDRO - Us Geological Survey (USGS); Moore, Matthew; KRUTZ, LARRY - Mississippi State University; PRINCE-CZARNECKI, JOBY - Mississippi State University; KROGER, ROBERT - Covington Civil And Environmental; BAKER, BETH - Mississippi State University; HOGUE, J - Us Army Corp Of Engineers (USACE); ALLEN, PETER - Mississippi State University

Submitted to: Journal of Soil and Water Conservation
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/2/2017
Publication Date: 5/15/2018
Citation: Omer, A.R., Miranda, L.E., Moore, M.T., Krutz, L.J., Prince-Czarnecki, J.M., Kroger, R., Baker, B.H., Hogue, J., Allen, P.J. 2018. Reduction of solids and nutrient loss from agricultural land by tailwater recovery systems. Journal of Soil and Water Conservation. 73(3):282-295. https://doi.org/10.2489/jswc.73.3.284.
DOI: https://doi.org/10.2489/jswc.73.3.284

Interpretive Summary: Tailwater recovery systems have been implemented as best management practices to address water quantity issues in the Mississippi Delta. Little research has been conducted on this practice's ability to improve water quality. Nutrient and solids concentrations in water were studied in six different tailwater recovery systems and compared between the inflow and outflow. Seasonal differences were noted, and loads of nutrients and solids were reduced through retention of the surface water in these systems. It is important to understand the water quality improvements offered through these tailwater recovery systems, but further study must be done in order to determine if they are economically feasible to maintain for the water quality benefit they offer.

Technical Abstract: Best management practices are being implemented throughout the Lower Mississippi River Alluvial Valley with the aim of alleviating pressures placed on downstream aquatic systems by sediment and nutrient losses from agricultural land; however, research evaluating the performance of one practice, tailwater recovery (TWR) systems, is limited. This study evaluated the ability of six TWR systems to retain sediment and nutrient draining from agricultural landscapes. Composite flow-based samples were collected during flow events (precipitation or irrigation) over a two-year period. Performance of TWR systems was evaluated by comparing concentrations and loads in water leaving agricultural fields and entering TWR systems (i.e. runoff or influent) to water overflow exiting TWR systems (effluent). In addition, performance was analyzed seasonally for adaptive management and insights into the impacts of landscape changes. Potential parameters influencing TWR system performance (i.e. effluent volume, system fullness, sampling method, season, time since the previous event, and system volume) were analyzed using factor and regression analyses. Tailwater recovery systems did not reduce solids and nutrient concentrations; however, loads of solids, P, and N were reduced by 43%, 32% and 44%, respectively. Influent and effluent of TWR systems showed no seasonal differences for analyte concentrations and loads. Performance of TWR systems was influenced by effluent volume, system fullness, time since the previous event, and capacity of the system. Mechanistically, TWR systems retain runoff on the agricultural landscape, thereby reducing the amount of sediment and nutrients entering downstream waterbodies. System performance can be improved through manipulation of influential parameters.