Potential economic impacts of groundwater conservation in the Mississippi River Alluvial Aquifer (MRAA), Louisiana, USA

Abstract

AbstractOverextraction of groundwater reduces groundwater height, increases the energy cost, and may threaten an aquifer's economic life. Water‐intensive crops, corn, and soybean, dominate the agricultural land in the Mississippi River Alluvial Aquifer (MRAA) region of the United States, thus stressing this confined aquifer. Groundwater conservation policy or the adoption of efficient irrigation technology could save both water and energy. This study aims to estimate the future returns from the irrigated land under the scenarios of 30%, 20%, 10%, 5%, and no groundwater conservation from 2020 to 2022. An accurate model to predict the crop choice decision is important to estimate the impact of groundwater policies. We develop a crop choice model where an individual farmer has a crop planting or land fallowing choice each year. We use the random forest, boosted regression trees, and support vector machine for the crop choice prediction. Boosted regression trees perform the best in our classification problem with 75.5% out of sample accuracy. The prediction model shows that the numbers of corn growers increase in the future. Our results show that the profit of 2572 farmers increased cumulatively by 0.14% when they conserve groundwater by 30% for 3 years. From a policy perspective, providing financial and technical assistant to farmers for making investments to conserve groundwater could save energy costs and sustain the economic life of the MRAA.Recommendations for Resource Managers Land allocations to water‐intensive crops such as corn and soybeans will expand in Louisiana. More efficient irrigation technology may reduce the groundwater extraction volume. Groundwater extraction volume using a choice prediction model gives a more accurate account of water use compared to the status quo crop choice decision scenario. Since efficient irrigation measures do not reduce crop yield, profit from the irrigated land is higher as it reduces the extraction cost. Government cost‐share to adopt efficient irrigation measures may help conserve groundwater resources.