Conservation Starts with Understanding the Trinity Aquifer

As we enter May, many Texans anticipate the onset of warmer temperatures and drier weather as early summer settles into its familiar pattern. As we transition into this seasonal shift, it's essential to take stock of the condition of various water sources in our region. Today, we turn our attention to the Trinity Aquifer, a crucial component of our local water supply.

 The Trinity system stretches across 61 counties from northeast of Dallas to southwest of San Antonio covering more than 10,000 square miles at the surface and more than 21,000 square miles below ground. It runs throughout much of the Hill Country, including all or portions of Kendall, Comal, Hays and Blanco counties, and is considered one of the "most extensive and highly used groundwater resources in Texas" by the Texas Water Development Board (San Antonio Express-News).

 According to the Aquifer Conservation Alliance, the Trinity Aquifer is a low production aquifer which recharges slowly, with only 4–5% of rain recharging it. Despite its slow recharge rate, it stands as one of Texas' most extensive and heavily used groundwater resources. Primarily utilized by municipalities, it also serves as a vital source for rural homes, irrigation, livestock, and other domestic uses.

 In July 2023, due to record-low levels in the Trinity, the Cow Creek Water Conservation District made the decision to transition to Stage 4 Drought Restrictions. This move was recommended following a presentation on the current hydrologic conditions in Kendall County. The Middle Trinity Aquifer's average water level, at 1177.20', dropped significantly, standing 24.02 feet below the July average, with a further decline of 5.82' since June 30th. Additionally, the District's 43 monitor wells showed a consistent downward trend, with 15 of them hitting record lows in July 2023. Stage 4 signifies a Drought Emergency, prohibiting lawn or turf grass watering using groundwater at any time. Stage 4 Drought persists today, with the water level averaging 1184.97 feet in April 2024. This marks a deficiency of 22.26 feet below the April average.

 The Trinity Aquifer faces significant challenges ahead. It is projected to be one of the most stressed aquifer systems in the state over the next 50 years due to its limited supply of groundwater and the pressures of population growth. This strain is intensified by factors such as drought, rapid urbanization, and an increasing number of wells tapping into its reserves.

 The implications of this strain are profound. Depletion of the Trinity Aquifer could result in lower lake levels, decreased spring flow resulting in reduced river and stream flow, and declining water tables within the aquifer itself. These consequences pose a threat not only to human communities but also to the delicate balance of ecosystems that rely on the aquifer's waters.

 Efforts to address these challenges are underway, with experts and policymakers seeking solutions to ensure the sustainable management and preservation of the Trinity Aquifer.

The Hill Country Alliance found that in the Texas Hill Country, up to 70 percent of potable water is used for landscaping, especially in the summer, presenting a huge opportunity to conserve water by shifting landscaping practices in the region. This organization also offers a step by step guide on how to landscape with native and drought tolerant plants and trees. 

 Through responsible stewardship and collaborative initiatives, we can work to mitigate the pressures facing the Trinity Aquifer, safeguarding its health and resilience for future generations.

 Cow Creek Water Conservation District, The Texas Water Development Board, and the Edwards Aquifer Authority closely monitor the Trinity Aquifer, recognizing its critical importance in maintaining the state's water supply. By understanding and appreciating the value of this aquifer, we can collectively strive to balance the needs of human communities with the preservation of our natural environment, ensuring that the Trinity Aquifer continues to nourish our landscapes and sustain our way of life for decades to come. Map courtesy of TWDB and Texas State University.