The Dockum investigation comes as Davis College looks toward a broader future for the New Deal facility. | Photos: Kadyn Collins
At a time when the future of agriculture on the High Plains is increasingly tied to the availability of groundwater, Texas Tech’s Davis College of Agricultural Sciences & Natural Resources is looking beneath one of its research farms for answers.
“This test well, and the water-quality, crop and livestock testing that follows, will help producers evaluate this resource as a potential pathway to continued profitable agricultural production,” said Darren Hudson, associate dean for strategic initiatives and assessment and the Larry Combest Endowed Chair for Agricultural Competitiveness.
Davis College is working with the High Plains Underground Water Conservation District (HPWD) and the U.S. Geological Survey (USGS) to evaluate the Dockum Aquifer beneath the New Deal Research Farm as a potential alternative or complementary source of groundwater for agricultural research.
The exploratory project comes as declining water availability from the Ogallala Aquifer, the region's principal source of irrigation water, has increased the urgency of understanding other groundwater resources.
Preliminary testing has already established that groundwater can be produced from the Dockum at the site. At a depth of about 420 feet, the exploratory well is producing approximately 2.76 gallons per minute.
The initial water-quality results, however, tell a more complicated story. Analyses indicate saline groundwater, with about 5,970 milligrams per liter of total dissolved solids and chloride concentrations exceeding 3,000 milligrams per liter.
For agricultural researchers, those numbers are not simply a warning about the limitations of Dockum water. They also present an opportunity to study how agriculture might adapt to lower-quality groundwater resources.
“This project is about understanding what the Dockum can provide, what its limitations are and how we might use that information to develop better strategies for agriculture in a water-limited environment,” said Alex Caldeira Rocateli, associate professor of integrated crop and livestock systems and director of campus farm operations in Davis College.
Preliminary testing has already established that groundwater can be produced from the Dockum at the site. | Photos: Kadyn Collins
The project is supported through a 60/40 cost-sharing partnership between HPWD and Texas Tech/Davis College. HPWD is providing 60 percent of eligible project costs, up to $30,000, while Texas Tech and Davis College are contributing the remaining 40 percent.
The arrangement allows the partners to combine resources and expertise to produce information that could have value beyond the college’s research farm.
A Three-Way Partnership
The collaboration brings together three institutions with different but complementary roles. Davis College contributes its expertise in agricultural science and its New Deal Research Farm, where researchers can examine the implications of water quality for crops, soils, irrigation and livestock systems.
HPWD brings regional knowledge of groundwater resources, water conservation and aquifer management. The district has conducted extensive investigations of the Dockum and other groundwater resources as the High Plains confronts confront long-term changes in the Ogallala.
The USGS adds expertise in hydrogeology, geophysics and subsurface characterization.
As part of the project, the USGS will use geophysical and other subsurface techniques to help develop a detailed profile of the geological formations encountered by the test well. The resulting information can help researchers understand the layers beneath the farm, identify water-bearing intervals and clarify the relationships among the Dockum, the Ogallala and other groundwater-bearing formations.
That information is particularly important in an area where groundwater resources can change substantially over relatively short distances.
“Having a better understanding of what is beneath the farm is essential to making informed decisions about future water development and research,” Rocateli said.
Water With Limits
The Dockum Aquifer, also known locally as the Santa Rosa Aquifer, is a Triassic-age geological formation that extends beneath more than 40 counties in West Texas and the Texas Panhandle.
It has attracted increasing attention as an alternative groundwater resource because it occurs beneath or near areas where the Ogallala Aquifer has been heavily relied upon for decades.
But the Dockum is not simply a deeper version of the Ogallala. Water quality varies considerably across the formation, and Dockum groundwater is frequently brackish or saline. Elevated concentrations of dissolved salts, chlorides and sulfates can make the water difficult to use directly for agricultural irrigation.
For crops, excessive salinity can interfere with a plant's ability to absorb water and can lead to the accumulation of salts in the soil. High sodium concentrations can also affect soil structure and reduce water infiltration.
Those characteristics mean that using Dockum groundwater for agriculture could require treatment, blending with higher-quality water, careful irrigation management or the selection of crops and forages with greater tolerance to saline conditions.
The preliminary results from the New Deal test well provide the kind of site-specific information necessary to begin evaluating those possibilities.
Rather than assuming the water will become a new irrigation supply, researchers can now ask more precise questions: How much water is available? How consistent is the supply? What treatment might be required? Could it be blended with other water sources? Which crops or forages could tolerate it? And would the cost of using it make economic sense?
Preparing for the Future
The exploratory well is not intended to become the farm's permanent production well. Eventually, the test well will be plugged. Its purpose is to gather information that can help determine whether a separate permanent Dockum research well nearby would be scientifically and practically justified.
If such a well is developed, it could give Davis College a rare opportunity to study agricultural production under saline-water conditions in the environment where those challenges are increasingly relevant.
Researchers could examine salt-tolerant crops and forages, irrigation practices, soil salinity, water-use efficiency and strategies for managing saline groundwater. Studies could also address livestock water quality, treatment and blending technologies, and the economics of incorporating lower-quality groundwater into agricultural production.
The research could extend beyond individual crops. Because the New Deal facility supports both crop and livestock research, a permanent well could become a platform for studying integrated crop-livestock systems in which water quality affects multiple components of agricultural production.
That possibility fits Rocateli's broader role at Davis College. At the New Deal Research Farm, he oversees facilities planning and management while working across research and outreach involving water conservation, grain, fiber, forage and animal production.
The farm itself is designed for that kind of interdisciplinary work. Its plant-science acreage supports research in irrigation management, water conservation, cotton physiology, abiotic stress tolerance, weed science, soil fertility and forage physiology. The larger New Deal operation includes livestock research involving beef cattle, dairy calves, swine and sheep and goats.
The Dockum investigation comes as Davis College looks toward a broader future for the New Deal facility.
“Finding and testing alternative water sources is a critical component of our Sustainable Water Systems strategic priority area,” said Davis College Associate Dean Hudson.
The research farm is being positioned for continued development as a research, education and outreach center serving faculty, students, producers and the agricultural industries of the Southern High Plains. Reliable water will be fundamental to that effort. But the project's potential significance extends beyond the boundaries of the farm.
CONTACT: Clint Krehbiel, Dean, Davis College of Agricultural Sciences & Natural Resources, Texas Tech University at (806) 742-2808 or Clint.Krehbiel@ttu.edu
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