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Improving Agricultural Water Use in the Texas High Plains: A Strategic Approach to Crop Switching and Optimal Land Allocation

This study finds that profit-maximizing crop reallocation among corn, cotton, and sorghum in the Texas High Plains can reduce regional groundwater use by nearly 22% without sacrificing farm profitability, with further water conservation opportunities being spatially concentrated and requiring significant economic trade-offs.

Original authors: DAVID AGBOLY, Shaihk Mafuz Rahman

Published 2026-10-07

📖 5 min read🧠 Deep dive

CC BY 4.0

Original authors: DAVID AGBOLY, Shaihk Mafuz Rahman

Original paper licensed under CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). ✨ This is an AI-generated explanation of the paper below. It is not written or endorsed by the authors. For technical accuracy, refer to the original paper. Read full disclaimer

In the vast, flat expanse of the Texas High Plains, the ground holds a secret that has sustained agriculture for a century but is now running dry. Beneath the soil lies the Ogallala Aquifer, a massive underground reservoir of water that farmers have relied on to grow crops in a region where rain is often too scarce to support them alone. For decades, this hidden water has been pumped up to irrigate fields of corn, cotton, and sorghum, but the water is leaving the ground faster than nature can refill it. This creates a difficult reality for the people who live and work there: they must find a way to keep their farms profitable while using less of a resource that is disappearing. The core question facing the region is not just how to save water, but how to do so without destroying the economic engine that drives the local community. Farmers must decide what to plant, knowing that some crops drink deeply while others are more thirsty for profit.

To answer this, researchers at Texas Tech University built a detailed computer model to test a simple idea: could farmers save massive amounts of water simply by changing what they grow, without needing to sacrifice their income? They looked at data from 41 counties across the Texas High Plains, covering the years 2000 through 2022. Instead of guessing, they used a method that simulates how farmers make decisions when prices for their crops go up and down unpredictably. They compared two different scenarios for every county. The first scenario asked, "What mix of crops would make the most money?" The second asked, "What mix of crops would use the least amount of water, provided the farmers still made almost as much money as they could have?" By running these simulations thousands of times with different price possibilities, the team could see exactly where the trade-offs existed and how much water could be saved if farmers shifted their land from water-hungry crops to more efficient ones.

The results revealed a surprising truth about the region's agriculture. When the researchers let the model find the most profitable way to use the land, the farmers in the simulation naturally switched away from water-intensive crops like corn and toward sorghum, which requires far less irrigation. This shift alone was powerful. Under the current mix of crops, the region uses about 2.27 million acre-feet of water annually. When the model optimized for profit, that number dropped to roughly 1.78 million acre-feet. This represents a reduction of nearly 22 percent, saving almost 500,000 acre-feet of water. Crucially, this massive saving did not come at the cost of the farmers' wallets; in fact, the model showed that by making this switch, the expected annual profit for the region would jump from about $275 million to over $1 billion. The most profitable path turned out to be the most water-efficient path.

The researchers then pushed the question further. They asked if there was even more water to be saved if farmers were willing to accept a tiny drop in their profits. They set a limit where farmers could lose up to 5 percent of their potential earnings in exchange for using less water. The result was that the total water savings increased only slightly, by about 2,900 acre-feet. This tiny gain came from just three counties: Donley, Roberts, and Randall. In the other 38 counties, the most profitable way to farm was already the same as the most water-efficient way. In those places, there was no hidden water to be found by changing crops; the farmers were already doing the best they could for both their bank accounts and the aquifer. The extra water savings in the three specific counties required a small financial sacrifice, costing the region about $272,000 in total expected profit to save those extra 2,900 acre-feet.

This led the researchers to calculate a specific cost for every extra drop of water saved, a metric they called the "Groundwater Abatement Price." In the three counties where extra savings were possible, the cost was relatively low, ranging from about $74 to $112 for every acre-foot of water conserved. However, if the researchers tried to force even more savings by allowing farmers to lose 10 percent of their profits, the cost skyrocketed. The price per acre-foot jumped to nearly $2,720, and the extra water saved was still relatively small compared to the massive loss in income. This suggests that the easy, low-cost opportunities to save water through crop switching have already been found by farmers acting in their own self-interest. The remaining water is much harder to save without significant economic pain.

The study concludes that the solution to the region's water crisis is not a single, uniform rule applied to every farm, but a recognition that the situation varies by location. For most of the Texas High Plains, the path forward is already clear: the crops that make the most money are also the ones that use the least water. Farmers do not need to choose between profit and conservation; the market has already aligned the two. For the few counties where a little extra water can be saved, it comes at a modest price, but trying to squeeze out more than that quickly becomes prohibitively expensive. The research offers a clear map for policymakers and producers, showing that strategic land allocation can secure the future of the aquifer, but it also warns that there are limits to what crop switching alone can achieve without deeper changes to the agricultural system.

Technical Summary: Improving Agricultural Water Use in the Texas High Plains

Problem Statement
Agricultural production in the Texas High Plains is increasingly constrained by water scarcity, specifically the depletion of the Ogallala Aquifer. While irrigation efficiency improvements have been pursued, they often fail to yield proportional reductions in total groundwater withdrawals due to rebound effects, such as the expansion of irrigated acreage or a shift toward more water-intensive crops. Consequently, crop choice and land allocation remain primary determinants of agricultural water demand. The central problem addressed is the trade-off between economic returns and groundwater conservation. Producers face heterogeneous conditions across the region, where water-intensive crops like corn and cotton offer high economic returns but strain water resources, while drought-tolerant crops like sorghum require less irrigation but may offer lower or more variable returns. The study seeks to determine if strategic reallocation of irrigated land among these three crops can reduce groundwater use without undermining farm profitability, and to quantify the economic cost of any additional conservation beyond profit-maximizing behavior.

Methodology
The study employs a county-level nested optimization framework covering 41 counties in the Texas High Plains using panel data from 2000–2022. The analysis focuses on three crops: corn, cotton, and sorghum.

Data Construction: Representative production parameters (yield, irrigation intensity, non-water production costs, and water prices) are derived using median values from the five most recent valid observations for each county-crop combination. This approach mitigates the influence of anomalous single-year data while preserving spatial heterogeneity.
Stochastic Optimization: The model incorporates price uncertainty using a kernel density estimation combined with Monte Carlo simulation (10,000 draws) based on historical prices from 2013–2022. This preserves the historical co-movement of crop prices while allowing for continuous variation.
Optimization Objectives:
- Profit-Maximizing (PMAX): Identifies the land allocation that maximizes expected net profit subject to fixed land and baseline water constraints.
- Water-Minimizing (WMIN): Identifies the allocation that minimizes irrigation water use while maintaining expected profit within a specified tolerance ( $\epsilon$ ) of the PMAX benchmark. The study evaluates $\epsilon$ values of 0, 0.05 (5%), and 0.10 (10%).
Strategy Space: The model evaluates 66 discrete land-allocation strategies (combinations of crop shares) for each county. Strategies violating the baseline water constraint are excluded.
Metrics: The study introduces the Groundwater Abatement Price (GAP), defined as the expected profit sacrificed per acre-foot of additional groundwater conserved when moving from the PMAX to the WMIN allocation.

Key Results

Profit-Driven Conservation: Reallocating land to maximize profit (PMAX) alone yields substantial water savings. Regional irrigation water use drops from a baseline of approximately 2.27 million acre-feet (AF) to 1.78 million AF, a 21.90% reduction. This shift is driven primarily by a move toward sorghum-dominant allocations.
Profitability Gains: The profit-maximizing reallocation is highly beneficial economically, increasing expected regional profit from $275.50 million to $1,081.74 million (a nearly fourfold increase), largely due to the shift away from high-cost, water-intensive crops.
Limited Additional Savings: Moving from PMAX to WMIN with a 5% profit tolerance yields only marginal additional water savings (an extra 2,903 AF, or 0.13% of the baseline). In 38 of the 41 counties, the PMAX and WMIN strategies are identical.
Spatial Concentration: The potential for additional conservation beyond PMAX is spatially concentrated. Only three counties—Donley, Roberts, and Randall—select different strategies under WMIN. These three counties account for all 2,903 AF of additional savings.
Groundwater Abatement Price (GAP): The regional weighted GAP for the additional conservation in these three counties is approximately $93.70 per acre-foot. However, this cost is not uniform: Randall County has the lowest GAP ($73.73/AF), while Donley has the highest ($112.39/AF).
Diminishing Returns: Relaxing the profit tolerance to 10% ( $\epsilon = 0.10$ ) yields significantly more water savings (an additional 15,149 AF) but at a drastically higher economic cost, raising the regional weighted GAP to approximately $2,720 per acre-foot.

Key Contributions

County-Level Assessment: The study provides a consistent, spatially explicit assessment of water-profit trade-offs across the Texas High Plains, avoiding the aggregation biases of regional averages.
Quantification of Divergence: It quantifies the divergence between profit-maximizing and water-minimizing allocations, identifying that for most counties, profit-oriented behavior already captures the majority of cost-effective water-saving potential.
Groundwater Abatement Price (GAP): The paper introduces the GAP as a policy-relevant metric to evaluate the economic opportunity cost of groundwater conservation, demonstrating that the cost of additional savings varies significantly by location.

Significance and Claims
The paper claims that strategic crop reallocation can achieve substantial groundwater conservation while simultaneously increasing farm profitability, suggesting that water conservation and economic viability are not inherently competing objectives in the Texas High Plains. The findings indicate that the "low-hanging fruit" of water conservation is largely captured by profit-maximizing behavior (the shift to sorghum).

The study modestly concludes that further conservation beyond the profit-maximizing allocation is possible but is spatially concentrated in a few counties and comes with increasing marginal economic costs. The authors assert that their framework provides a practical decision-support tool for policymakers and producers, highlighting that conservation policies should be spatially differentiated to account for the varying economic costs of water savings rather than applying a uniform regional approach. The paper does not claim that crop switching alone solves the aquifer crisis but rather that it is a critical component of a cost-effective management strategy, with the remaining conservation opportunities being limited and location-specific.

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