Drought, data and Bulletin 6110
In Presidio County there’s been a lot of talk lately about groundwater and data centers. The topic is not without its anxieties because data centers reportedly use a lot of water, and Texas appears mired in yet another major drought. The statewide drought of the 1950s, which lasted from 1949 to 1957, was the most significant such event in Texas history. Also known as the “drought of record,” it was the worst “in terms of duration and intensity,” according to the Texas Water Newsroom, and led to the formation of the Texas Water Development Board (TWDB).
An important role of TWDB involves studying the state’s groundwater resources through the collection of data. Cody Bjornson is a TWDB hydrologist based in Marfa who spends a lot of time collecting and analyzing data. As a groundwater monitoring specialist in Far West Texas, Bjornson told “Our Water Matters” that the biggest question for him is: “How do groundwater conditions from the late 1950s compare to now?” In his search, he came across Bulletin 6110, a TWDB publication from 1961. Formally titled “Groundwater Reconnaissance of the Marfa Area, Presidio County, Texas,” Bulletin 6110 was compiled from data acquired during field studies in 1958 and 1959 in the immediate aftermath of the drought of record. The bulletin “answered a lot of my questions about the aquifer system here,” says Bjornson. “I made it my goal to update Bulletin 6110.”
The bulletin cites baseline data obtained “from an inventory of 111 wells” in the Marfa area, which is defined as “approximately 350 square miles in the northeast corner of Presidio County.” Within the study area, groundwater occurs “under both water-table and artesian conditions in different places,” according to the bulletin. “Although the ground water may occur … under either confined or unconfined conditions, the confined water rises to approximately the same general level as the water table of the area, suggesting that the aquifers underlying the area are interconnected.”
The bulletin identifies the Tascotal formation and other water-bearing units that probably underlie “the area extending from U.S. Highway 90 southward to the Santa Fe Railroad and from U.S. Highway 67 eastward to the Antelope Springs ranch road” as “the most productive aquifer in the Marfa area, yielding as much as 1,200 gallons per minute to some wells.” This is particularly noteworthy because the currently proposed data center — if ultimately constructed — would occupy precisely this area. Bjornson and his update of Bulletin 6110 could provide the groundwater district with the pivotal data necessary to ensure the best possible management of this crucial formation in the region.
The bulletin states that “ground water in the Marfa area is derived from precipitation on the area and the natural recharge is estimated to be on the order of 8,000 acre-feet annually. This exceeds [late 1950s groundwater] pumping by more than 7,000 acre-feet.” By obtaining current levels in wells from the original bulletin, Bjornson can then compare them with the baseline levels and other data to arrive at a clearer picture of overall aquifer health over time. This work, along with updated precipitation and recharge analyses by Dr. Kevin Urbanczyk and others, could elucidate the pumping levels that are most sustainable by large-scale industrial users now and into the future.
In his efforts to update the bulletin, Bjornson has measured nearly all of the 111 wells included in the 1961 report; however, accessing “privately-owned wells is a consistent obstacle,” he says. “When I started this project over a year ago, access did not look promising. But with the help of others … I was able to gain access to a couple of large ranches with wells that are important data points.” Bjornson acknowledges that it’s a team effort. “I could not complete this project without the help of others, especially David Williams, who has also devoted his limited time to helping me with access, well information, and opening lots of gates. It may not seem like it, but there are more moving parts to accessing and measuring water levels in 100-plus wells than you would think.”
As with many arduous projects, the bulletin update also has its rewards. “The majority of the wells in this study are embedded in ranching history and have their own names and quirks,” says Bjornson. “I get to hear all about those stories from the ranchers who join me in the field … [and] … I’m able to piece together all the things I need to know to ensure I’m acquiring the best data possible from the correct wells.”
Elmer Kelton’s novel titled The Time It Never Rained tells the tale of a small West Texas town suffering through the drought of the 1950s. “Each new generation tends to forget,” Kelton writes, “until it confronts the sobering reality — that dryness has always been the normal condition in the western half of the state.” At just 30 years of age, Bjornson can certainly be considered part of a new generation. But his pursuit of answers from the drought of record not only thwarts the amnesia Kelton describes, it also enhances our region’s capacity to confront the next sobering reality headed our way.
To read the bulletin, visit https://pcuwcd.org/district-documents and click on Bulletin 6110.Trey Gerfers serves as general manager of the Presidio County Underground Water Conservation District. A San Antonio native, he has lived in Marfa since 2013 and can be reached at tgerfers@pcuwcd.org.
