Uvalde Water Hardness & Quality Report (2026)

Uvalde, Texas, in Uvalde County — the Uvalde County seat adjacent to Sabinal and Hondo on the Frio River and Nueces River in southwest Texas Hill Country — receives its municipal water from the Uvalde Water Division, drawing from the Nueces River and local Edwards Aquifer wells (Uvalde County) through the Uvalde treatment system.

The extremely hard 343.5 mg/L hardness and very high TDS of 992.2 mg/L reflect the southwest Texas Edwards Plateau's intense calcareous character. The Nueces River at Uvalde drains the Edwards Plateau — Cretaceous Edwards Group limestone (the dominant Texas Hill Country carbonate platform — very high purity limestone, the primary recharge zone of the Edwards Aquifer), Cretaceous Buda Limestone (very high purity carbonate), and Cretaceous Comanche Peak Formation (calcareous). The Edwards Plateau's exceptionally pure limestone lithology produces an inherently very hard water supply, compounded by the Edwards Aquifer groundwater contribution (also very hard).

At 343.5 mg/L with TDS 992, Uvalde's water is extremely hard. A water softener is essential and critical. Scale forms immediately on all surfaces, appliance lifespans are critically shortened, and water heaters fail within 2-3 years without softening. The PFAS level of 10.3 ppt warrants a certified reverse osmosis drinking water filter — the Laughlin Air Force Base (Del Rio, Val Verde County — AFFF, the dominant southwest Texas military PFAS source in the Edwards Plateau drainage area), and the southwest Texas PFAS background contribute to Uvalde's elevated readings.