Water Quality Considerations for Using Surface Water Bodies as an Alternative Irrigation Water Source in the Mississippi Alluvial Plain, Mississippi, USA

Authors: Witthaus, Lindsey; Lizotte Jr, Richard; Heintzman, Lucas; Taylor, Jason; Moore, Matthew; PAWLOWSKI, ETHAN - Oak Ridge Institute For Science And Education (ORISE); Langendoen, Eddy; Locke, Martin

Submitted to: Journal of Soil and Water Conservation
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/18/2026
Publication Date: 2/10/2026
Citation: Witthaus, L.M., Lizotte Jr, R.E., Heintzman, L.J., Taylor, J.M., Moore, M.T., Pawlowski, E.D., Langendoen, E.J., Locke, M.A. 2026. Water Quality Considerations for Using Surface Water Bodies as an Alternative Irrigation Water Source in the Mississippi Alluvial Plain, Mississippi, USA. Journal of Soil and Water Conservation. https://doi.org/10.1080/00224561.2025.2579489.
DOI: https://doi.org/10.1080/00224561.2025.2579489

Interpretive Summary: Row crop agriculture in Mississippi uses irrigation to reach optimal production levels. However, overuse of groundwater for irrigated agriculture has led to declines in levels of the Mississippi Alluvial Aquifer. Resource managers are searching for alternative strategies and sources of irrigation water to improve the sustainability of the aquifer. Surface waterbodies are plentiful in the Mississippi Alluvial Plain (MAP) region, but more information is needed on the ecological impacts of using surface water for irrigation. We present results from a regional case study lake that is used for irrigation, Roundaway Lake, to demonstrate the impacts of irrigation on water temperature and dissolved oxygen levels, two critical waterbody characteristics that affect ecological health. To assess the potential availability of surface water in lakes across the MAP, we used geospatial datasets to identify 392 waterbodies that are of adequate size to support irrigation needs. Finally, we present concepts that could improve dual management of waterbodies for both irrigation and supporting healthy ecosystems, such as water retention structures or dredging to increase lake depth and water capacity.

Technical Abstract: Irrigated agriculture is a leading cause of unsustainable groundwater depletion, and there is a need for creative water management strategies. Surface water is plentiful in the Mississippi Alluvial Plain (MAP) and under-utilized as a source of irrigation, but information is needed on ecological impacts of using surface water for irrigation. We present results from a regional case-study watershed, Roundaway Lake, to examine the use of lentic surface water irrigation for agriculture and its potential ecological effects. Irrigation from Roundaway Lake during summer of 2018 showed decreased water depths from 1.35 to 0.70m at peak irrigation. The decrease in lake water depth increased maximum water temperatures, temperature range, chlorophyll a, algal health, and decreased minimum dissolved oxygen (DO), demonstrating intermittent water quality impacts. We also assessed available lentic surface waterbodies that could serve as agricultural irrigation water sources using 1-m resolution elevation data. Our analysis found 392 waterbodies in the MAP sub-region of potential size for irrigation. With an estimated waterbody surface area to volume ratio of 11,000m3 ha-1, this represents greater than 8.2Mm3 of available surface water. Finally, we provide some considerations for dual management of lentic waterbodies for irrigation and ecological services. Restoration activities, including water retention structures to elevate lake levels and/or dredging lake sediments to create deeper pools in lake basins, can increase lentic surface water volume for irrigation and provide more depth during irrigation withdrawals to support ecosystem services. Water resource managers should consider including enhancement of lake habitats when planning for surface water irrigation within the region to create more sustainable, dual management options for agriculture and the environment.