Brief Summary of Minutes of Annual Meeting

Objective 1: Characterize the response of water resource and human systems to climatic and anthropogenic perturbations

California (Dinar, Mahajan, Ying, Nemati, Schwabe, D'odorico)

(Schwabe) Co-authored paper titled "Cultivating Climate Resilience in California Agriculture: Adaptations to an Increasingly Volatile Water Future” that highlights areas in which California agriculture is vulnerable to climate change, drought, and water scarcity and identifies management strategies and policy options to reduce its vulnerability over the next 50 years. In addition, collaborating on USDA-NIFA funded project to compare different agricultural land use schemes under water scarcity – i.e., fallow vs water-limited–in terms of short and long term profits, soil quality, dust (pm-10) generation, and carbon sequestration.

Georgia (Mullen)

Evaluated the water quantity and water quality implications of expanding vegetable production in the southeast under historical and future climate conditions. Switching from traditional cotton-peanut row crop production to vegetable crops would nearly double water withdrawals per acre. In general, pesticide risks to groundwater are higher for row crop systems in the southeast, while pesticide risks to surface water are higher for vegetable crop systems. Nitrogen and phosphorous application rates are also higher in vegetable cropping systems than row crop systems. This analysis is reported in the journal Sustainability.

Idaho (Maas)

Calculated crop acreage change and corresponding if evapotranspiration volumes for the East snake plane aquifer. This work was presented to the Idaho Dairyman's Association, and the Rural Agricultural Appraisers Association.

Kansas (Hendricks, Sampson)

We estimated how irrigation withdrawals respond to changes in precipitation and evapotranspiration and find that farmers decrease water use by less than one inch for an additional inch of precipitation. We use the results of how farmers change their water use as weather changes to project changes in water use by mid-century due to climate change. We then estimate how the projected changes in water use translate to changes in the rate of aquifer depletion across different parts of the High Plains Aquifer. Climate change is expected to increase groundwater withdrawals which will accelerate the decline in aquifer water levels and is therefore important to consider when projecting future aquifer conditions.

Michigan (Asher, Nejadhashemi)

Using the evolutionary multi-objective optimization concept, we developed a novel method to optimize Best Management Practices implementation to reduce the impacts of human activities. By integrating re-optimization strategies and transfer learning, we enhanced decision-making efficiency.

Mississippi (Quintana Ashwell)

Identified excess groundwater pumping driven by irrigation associated with high heat during the growing season. The excess irrigation is of such a magnitude that it decoupled irrigation applications from in-season precipitation and evapotranspiration. A review of the literature reveals that across the corn belt, university extension bulletins identify leaf curling or flipping as a signal of water stress. This is a highly visual “trigger” for irrigators who overwhelmingly still rely on visual crop cues to initiate irrigation events. We verify with soil moisture sensors in research plots that soybean leafs flip and corn leafs curl even when there is adequate soil moisture.

Oklahoma (Jafarzadegan, Lambert)

Worked with researchers from Oklahoma, Kansas, and Texas on application of USDA-SAS grant (title: Sustainable Irrigation and Climate Adaptation in Southern Hight Plains: a Satellite-Enabled and Peer-Led Model). $10,000,000 was awarded to the research team. We also estimated impacts of local enhanced management area (LEMA) on groundwater use reduction, change in pumping costs, and irrigated crop production from 2013 to 2023.  

South Carolina (Jeong)

We, Dawoon Jeong from South Carolina and Gabriela Perez-Quesada from Tennessee, estimated how farmers in South Carolina adopt irrigation in response to peer effects and drought levels.

Texas (Wilcox, Dominguez, Rouhi Rad)

Published a manuscript on modeling human-groundwater systems. The paper introduces a model that fully integrates groundwater aquifer system with producer irrigation decisions that are informed by an agronomic model. 

Developed a manuscript on the effects of hot days on irrigation electricity demand. Our results demonstrate that, in the short-run, an additional day above 30◦C results in about 0.4% increase electricity use for irrigation and irrigators’ spending on electricity. In the long-run, results suggest that higher temperatures result in more wells as well as more electricity use for each well. Importantly, we find that the magnitude of long-run response is considerably larger, 3.9%, compared to short-run response suggesting an increased reliance on groundwater as a climate adaptation and resilience strategy in US agricultural production over the past three decades

Estimated the effects of wildfires on water quality and quantity. We study how two wildfires in California (Tubs fire and Thomas fire) have affected streamflow and water quality.

Developed a manuscript on the interaction between water scarcity and salinity in irrigated agricultural production. We show that water scarcity can worsen the negative effects of salinity on irrigated agriculture. 

Objective 2: Quantify the use, non-use, and natural capital (flows and stocks) value of water in different stages of the water cycle

California (Mahajan, Ying, Edwards, Schwabe, D'odorico)

(Schwabe) Investigating the role of return flows from irrigated agriculture on ecosystem services and human health in the Salton Sea with the Salton Sea Task Force and how adjustments in Colorado River flows that might arise from the 2026 water sharing agreements might influence those outcomes as well as agricultural productivity in Imperial Valley.

Kansas (Sampson, Hendricks)

Using information from southcentral and southwest Kansas, we compared irrigators’ stated concerns about their water quality and water quantity with the history of irrigated acreage, total water use, and crop choices. We find that irrigators indicating elevated concern over either groundwater quality or groundwater quantity correlates with less total water use, fewer total irrigated acres, and fewer acres of irrigated corn. Additionally, concerns over groundwater quantity generally correlate with a greater reduction in water use along multiple water use margins compared to equal concerns over groundwater quality.

We developed a model that estimates the economic cost of aquifer depletion. We estimate the economic impact of projected depletion of the High Plains Aquifer. When the initial saturated thickness is less than 70 feet, most of the economic impact (63%) of a decrease in the stock of groundwater occurs through an adjustment in irrigated acreage (extensive margin), while 37% occurs through reduced irrigated rental rates (intensive margin). When saturated thickness is larger, nearly all of the response is at the extensive margin. Simulation results reveal that the average annual present value of returns to land are expected to decrease in the High Plains region by $120.6 million in 2050, and by $250.5 million in 2100.

Louisiana (Zheng)

We developed a two stage model that integrates the recreational demand model with the hedonic model. This approach gives us a more comprehensive estimate on the value of water quality, including both use value and non-use value of water. We applied this approach to three regions in the US: Long Island Sound, Puget Sound and Texas Gulf Coast. 

Tennessee (Perez Quesada)

Collaborated with colleagues at Kansas State University to develop a model that estimates the economic cost of aquifer depletion (described above).

We utilize high-resolution data on crop production and groundwater levels to estimate the nonlinear impacts of groundwater levels for corn and wheat production across the High Plains Aquifer in the central United States. This analysis reveals that continuing the current path of depletion will decrease corn and wheat production in the region by 6.75% and 1.08% in 2050, with the impacts primarily arriving via reductions in irrigated acreage. We provide evidence of substantial spatial heterogeneity of these impacts, which is notable for a region that employs largely homogeneous technology and management practices throughout. The largest production losses are associated with the Central and Southern portion and are as large as 40% for corn production in the Texas portion of the aquifer. 

Texas (Wilcox, Dominguez, Rouhi Rad)

Developed a manuscript that estimates the value of access to water, and the security of access to water captured by water rights seniority using agricultural land transactions in Colorado. We find a large but heterogeneous value for access to irrigation.

Developed a manuscript on the introduction of non-market valuation method used for valuation of water quality 

Objective 3: Evaluate and compare alternative strategies and institutions to manage water quantity and quality, and the relationship to ecosystem, communities, land, and energy uses

California (Dinar, Mahajan, Ying, Edwards, Nemati, Schwabe, D'odorico)

(Schwabe) As part of a USDA-NIFA project, investigating how the use of AI can influence water use in semi-arid and arid regions and consequent impacts on agricultural profits as well as runoff and the nutrient loads in the runoff.

Georgia (Mullen)

We estimated agricultural water demand systems for the southeastern US (TX, LA, AR, MS, AL, TN, GA, FL, NC, SC, VA) using USDA FRIS and IWMS data. In Georgia, the own-price elasticity of irrigation water was negative but very inelastic across the 4 crops investigated (cotton, peanut, corn, and soybean), while the output price elasticities of irrigation water were positive and inelastic for the same crops. At the regional level, the output price elasticities of  irrigation water were also positive and inelastic, although the own-price elasticities were not significantly different than zero.

Idaho (Maas)

Awarded an $800,000 USDA-NIFA grant to investigate the impacts of land use change, water scarcity, and weather on particulate matter (air quality concentrations).

Published a peer-reviewed review article for estimating water demand in PLOS-Water.

Published a peer-reviewed article in Water Resources Research investigating how location and development along a water way impact total value of water within the watershed.

Kansas (Sampson, Hendricks)

We conducted an experiment where we provide information to irrigators about how much water they use compared to neighboring users. Our experiment randomizes who received the information and who did not. We find that irrigators that received the information decreased their water use by about 4%. This indicates that significant water savings can be achieved at a very low cost by simply providing irrigators with information about how their water use compares to their peers.

We also wrote a paper that describes the importance of water institutions for proper water management, especially given the challenges faced by climate change. This paper synthesizes the relevant academic literature and also identifies key knowledge gaps for future research.

We surveyed irrigators in Groundwater Management District 5 in southwest Kansas. The survey collected information on irrigation management practices and challenges facing irrigators. Survey respondents near unanimously view regulatory uncertainty, including the risk of reduced allocations, as a top concern confronting the future of irrigation in the region. Drought, energy costs associated with operating pumping plants, and reduced pumping capacities are also highly cited as irrigation challenges and concerns. Crop consultants, the producer’s own past experiences, and peer producers rank the highest in terms of reliable provision of information.

Michigan (Asher, Srivastava, Ghane, Sears, O’Neil)

Field-scale outcomes: We evaluated two water management strategies at the subsurface-drained fields in southeast Michigan. These strategies included controlled drainage and saturated buffers. Both strategies showed promising flow and nitrate load reduction. In terms of phosphorus performance, the strategies presented inconclusive benefits. We will continue evaluating these strategies in 2025 to determine their effectiveness for phosphorus reduction.

Decision-support tool outcomes: We evaluated the USDA’s GSSURGO soil database for use in decision-support tools. Our DRAINMOD field-scale modeling showed that the soil database can reasonably predict water quantity from a subsurface-drained field. Our next step is to develop the decision-support tool to predict site-specific water quantity in subsurface-drained fields.

We evaluated the costs of using institutional controls to manage groundwater contamination in Michigan. It was determined that a lot of hidden costs were associated with this management approach and that the value of various ecological services and long-term use of the aquifers in these areas were often underestimated. A decision-support tool was developed to assist the state with assessing the long-term costs of using institutional controls and to explore alternative management approaches. 

We assessed phosphorus pollution and its relationship with market prices for fertilizer, corn and soybeans. We also assessed how irrigation adoption has been shifting across Michigan. 

Mississippi (Quintana Ashwell)

Applying survival analysis methods to data from a survey of irrigators identified the accelerating effect of state-level USDA-NRCS funding on water-conserving practice adoption. Each additional million dollars of funding is associated with 3% faster adoption of computerized hole selection and 22.5% faster adoption of center pivot irrigation. Poisson count models indicated that participation in NRCS programs influenced the number of practices adopted but not any particular practice. The announcement of the Governor’s Delta Water Resources Task force in 2012 seems to have introduced some uncertainty among producers and was associated with 1.5 and 6 times longer adoption time for computerized hole selection and center pivot, respectively.  

Oklahoma (Jafarzadegan, Lambert)

 Lixia Lambert with student and colleagues: conducted drought and federal crop insurance program impact analysis. The study quantified the direct and indirect economic losses experienced by five counties in southwestern Oklahoma that experienced exceptional drought at some point from 2000 to 2021 and determine how losses are moderated by Federal Crop Insurance indemnities for corn, cotton, and wheat.

 Lixia Lambert with Lucia Levers: developed a manuscript based on investigating optimal cropping patterns and changes in energy costs and water table in Oklahoma Panhandle region with respect to different extraction constraints.

Texas (Dominguez, Rouhi Rad)

Developed a manuscript estimating the marginal abatement cost (MAC) curve for irrigation water in the Colorado River Basin using operation-level data on crop choice decisions. We show the heterogeneity of abatement costs across the states and basins due to the types of crops produced.

Developed a manuscript on regulating non-point source pollution from the stormwater. Our preliminary results show that the MS4 policy resulted in significant declines in water pollution (turbidity, TSS, phosphorus).

Developed a manuscript to study the impact of the Reclamation Act on agricultural development and population dynamics in the western United States. We find that the Act increased irrigation acres and yields for some crops, which resulted in increases in land values. It also increased population. 

California 

Medellin-Azuara, J., Escriva-Bou, A., Gaudin, A., Schwabe, K. and Sumner, D. 2024. "Cultivating Climate Resilience in California Agriculture: Adaptations to an Increasingly Volatile Water Future.” Proceedings of the National Academy of Sciences 121 https://doi.org/10.1073/pnas.2310079121.

Kansas 

Gardner, Grant, and Gabriel S. Sampson. 2024. "Groundwater quality vs. groundwater quantity. Combining information on irrigator concerns with past water use and cropping behavior." Water Resources and Economics 47: 100246.

Sampson, G. S., Aguilar, J., Baldwin, C., Davidson, J., and Mehl, H. 2024. Water Management and Information Gaps in the High Plains Aquifer. Journal of the ASFMRA, 2024:116-129.

Orduña Alegría, Maria Elena, Sam Zipper, Hoon C. Shin, Jillian M. Deines, Nathan P. Hendricks, Jonah J. Allen, Geoffrey C. Bohling, et al. 2024. “Unlocking Aquifer Sustainability through Irrigator-Driven Groundwater Conservation.” Nature Sustainability. https://doi.org/10.1038/s41893-024-01437-0

Zhao, J., N.P. Hendricks, and H. Li. 2024. “Groundwater Institutions in the Face of Global Climate Change” Annual Review of Resource Economics 16:125-141. https://doi.org/10.1146/annurev-resource-101623-100909

Perez-Quesada, G., N.P. Hendricks, and D.R. Steward. 2024. “The Economic Cost of Groundwater Depletion in the High Plains Aquifer.” Journal of the Association of Environmental and Resource Economists 11(2): 253-285. https://doi.org/10.1086/726156

Hrozencik, R.A., J.F. Suter, P.J. Ferraro, and N. Hendricks. 2024. “Social Comparisons and Groundwater Use: Evidence from Colorado and Kansas.” American Journal of Agricultural Economics 106(2): 946-966. https://doi.org/10.1111/ajae.12415

Louisiana 

Lisk, M. D., Grogan, D. S., Zuidema, S., Zheng, J., Caccese, R., Peklak, D., ... & Fowler, L. (2024). Harmonized Database of Western US Water Rights (HarDWR) v. 1. Scientific Data, 11(1), 598.

Michigan 

M.A. Askar, E. Ghane, M.A. Youssef, V.S. Shedekar, K.W. King, R. Bhattarai. 2024. Feasibility of predicting subsurface drainage discharge with DRAINMOD parameterized by uncalibrated SURRGO soil properties and ROSETTA3. Journal of Natural Resources and Agricultural Ecosystems. 22, 1-10. https://doi.org/10.13031/jnrae.15735

Masri, Z., J. Asher, and J. R. Piwarski. 2024. Reduction of Nitrate Leaching and Threats to Surface Water Under Conservation Tillage. Journal of the American Society of Agricultural and Biological Engineers, 67(3): 573-588. doi: 10.13031/ja.15533 

O'Neil, G., Miller, S., Dempsey, D., Flaga, C., & Mann, J. (2024). Institutional Controls for Groundwater Management: Long Terms Costs and Policy Impacts. Michigan Department of Environment, Great Lakes, and Energy – Office of the Great Lakes Award GL21-MSU-01.

Kropp, I., A. P. Nejadhashemi, K. Deb, 2024. Improved Evolutionary Operators for Sparse Large-Scale Multi-objective Optimization Problems, IEEE Transactions on Evolutionary Computation, 8(2): 460-473.

Deb, K., A. Pouyan Nejadhashemi, G. Toscano, H. Razavi, L. Linker, 2024. Leveraging innovization and transfer learning to optimize best management practices in large-scale watershed management, Journal of Environmental Modelling and Software, 180: 106161.

Kpodo, J, P. Kordjamshidi, A. Pouyan Nejadhashemi, AgXQA: A Benchmark for Advanced Agricultural Extension Question Answering, Computers and Electronics in Agriculture, 225: 109349.

Sarkar, Sampriti, Preet Lal, Molly Sears, Frank Lupi. (2024) “Evaluating the impact of fertilizer and crop prices on phosphorus concentrations in Great Lakes watersheds.” Journal of the Agricultural and Applied Economics Association. https://doi.org/10.1002/jaa2.145

Mississippi 

Quintana-Ashwell, N. E., Al-Sudani, A., & Gholson, D. M. (2024). The cost of mismanaging crop heat stress with irrigation: Evidence from the mid-south USA. Agricultural Water Management, 300, 108907.

Roberts, C., Gholson, D., Quintana Ashwell, N. E., Locke, M., Pieralisi, B., Spencer, G., Crow, W., Krutz, L. J (2025). Economic implications of reduced tillage and cover crops in the irrigated mid-South. Agronomy Journal. https://doi.org/10.1002/agj2.70034.

Russell, D., Singh, G., Quintana-Ashwell, N., Kaur, G., Gholson, D., Krutz, L. J., & Nelson, K. A. (2024). Cover crops and irrigation impacts on corn production and economic returns. Agricultural Water Management, 295, 108739.

Oklahoma 

Lambert, DM, LH Lambert, J Ripberger, H Jankins-Smith, & CL Silva. (2024) Public support for producer adoption of soil health practices. Agriculture and Human Values. https://doi.org/10.1007/s10460-024-10660-6

Welch, KL, DM Lambert, LH Lambert, & A Hagerman. (2024). The effects of disaster relief insurance on drought impacts: a case study of southwest Oklahoma. Review of Regional Studies 54, 215-240. 

Tennessee (Perez Quesada)

Perez-Quesada, G., Hendricks, N.P., Tack, J. and Steward, D.R. 2024. Adapting crop production to water scarcity. Environmental Research Letters, 20(1), p.014029.

Texas (Wilcox, Dominguez, Rouhi Rad)

Nozari, S., Bailey, R.T., Rad, M.R., Smith, G.E., Andales, A.A., Zambreski, Z.T., Tavakoli-Kivi, S., Sharda, V., Kisekka, I., Gowda, P. and Schipanski, M.E., 2024. An Integrated Modeling Approach to Simulate Human-Crop-Groundwater Interactions in Intensively Irrigated Regions. Environmental Modelling & Software, p.106120.

Guerrero, V.L., Sahoo, D., Dickes, L., Walker, T., Rouhi Rad, M. and Allen, J., 2024. Adap-

tive Water Governance in an Interest-Based Stakeholder-Driven Water Resource Planning Institution in South Carolina, US. Journal of Water Resources Planning and Management, 150(6), p.05024004.