Austin, Texas, has a population problem — and it’s directly connected to its water supply.
The Texas capital has grown from about 800,000 residents in 2010 to well over 1.1 million in the city proper, with the metro area exceeding 2.3 million. That growth has put extraordinary pressure on a water supply that was already stretched by recurring Texas droughts.
Austin Water draws primarily from the Colorado River of Texas (not to be confused with the Colorado River that feeds Lake Mead) through the Highland Lakes system — a chain of reservoirs including Lake Travis and Lake Austin that were built in the 1930s and 1940s by the Lower Colorado River Authority (LCRA).
The Highland Lakes: Feast or Famine
The Highland Lakes system is defined by extremes. Texas rainfall patterns create cycles of severe drought followed by intense flooding, and the reservoirs swing between dangerously low and spillway-full.
During the 2011 drought — the worst single-year drought in Texas recorded history — Lake Travis dropped to about 40% capacity. Mandatory water restrictions were imposed across the Austin metro, and LCRA curtailed water deliveries to downstream agricultural users for the first time.
The 2011-2015 drought period forced Austin to confront the limits of its water supply:
- LCRA’s Water Management Plan was revised to prioritize municipal and industrial users (including Austin) over agricultural irrigation during drought
- Austin Water invested in conservation programs that reduced per capita consumption significantly
- New supply development including the potential for water reuse and aquifer storage was elevated in planning priorities
But drought always returns in Texas. And each drought hits a larger population with higher baseline demand.
PFAS: An Emerging Concern
PFAS contamination has been detected in Austin-area water sources, though the picture is still developing.
Key sources of concern:
- Camp Mabry — The Texas Military Department’s primary installation, located in central Austin, has a history of AFFF use. While the site is relatively small, its urban location means any groundwater contamination is near residential areas.
- Austin-Bergstrom International Airport — Like all major airports, ABIA has used AFFF firefighting foam. PFAS in groundwater near the airport has been detected in preliminary sampling.
- Former military installations — Central Texas has multiple former and active military facilities, including Fort Cavazos (formerly Fort Hood) about 60 miles north, where extensive PFAS contamination has been documented.
- Industrial sources — Austin’s growing semiconductor and technology manufacturing sector uses PFAS compounds in production processes, raising questions about industrial discharges.
Austin Water has been testing for PFAS under EPA’s UCMR 5 program and has reported results generally below the new federal MCLs. But the regulatory landscape is tightening, and treatment upgrades may be needed as more data becomes available.
The Colorado River: Everything Upstream Matters
Austin’s raw water quality is influenced by everything upstream in the Colorado River watershed. Key concerns:
- Agricultural runoff — The Colorado River basin upstream of Austin includes significant agricultural land. Fertilizer, pesticide, and sediment runoff affect source water quality, particularly during storm events.
- Treated wastewater discharges — Multiple communities upstream of Austin discharge treated wastewater into the Colorado River and its tributaries. While these discharges meet permit requirements, they introduce pharmaceuticals, nutrients, and trace contaminants.
- Algal blooms — Lady Bird Lake (the impoundment that flows through downtown Austin) has experienced toxic cyanobacterial (blue-green algae) blooms. In 2019, several dogs died after exposure to algal toxins in the lake. While Lady Bird Lake isn’t a direct drinking water source, the blooms reflect broader nutrient loading in the watershed.
- Mining and industrial legacy — The Highland Lakes region has historical mining activity that has left trace metals in some tributaries.
Austin Water operates three treatment plants — Ullrich, Davis, and Handcox — that use conventional treatment processes including coagulation, sedimentation, filtration, and disinfection.
Infrastructure: Building Fast Enough?
Austin’s infrastructure challenge is straightforward: the city is growing faster than it can build water and wastewater capacity.
- Treatment plant capacity — Austin Water has been expanding its treatment plants to keep pace with growth, but capital projects take years to plan and build, while new residential developments continue at a rapid pace.
- Distribution system — New developments require new water mains, pump stations, and storage tanks. Meanwhile, older parts of Austin have aging infrastructure that needs replacement.
- Wastewater capacity — South Austin Treatment Plant and Walnut Creek Treatment Plant both face capacity constraints during peak flow events.
- Water reuse — Austin has invested in recycled water for irrigation and industrial use, but potable reuse (treating wastewater to drinking water standards) is not yet part of the supply portfolio. Other Texas cities, including El Paso, are further along on this front.
Private Wells in the Austin Area
The Austin metro area sits over the Edwards Aquifer (primarily to the south and west) and the Trinity Aquifer. Many suburban and exurban communities rely on private wells or small water systems tapping these aquifers.
Key concerns for well owners:
- Nitrates — Septic systems and agricultural operations in the Hill Country contribute nitrate contamination to shallow groundwater
- Arsenic — Naturally occurring arsenic has been detected in some wells in the greater Austin area
- Bacteria — After heavy rain events, shallow wells can be vulnerable to bacterial contamination
- Edwards Aquifer recharge zone — Development over the aquifer’s recharge zone in western Travis and Hays counties threatens long-term groundwater quality
The Texas Commission on Environmental Quality (TCEQ) regulates public water systems, but private well owners are responsible for their own testing and treatment.
What Austin Residents Should Know
- Read your water quality report. Austin Water publishes annual results with detailed testing data. Pay attention to PFAS, DBPs, and any contaminants specific to your service area.
- Conserve water. Austin’s supply is not unlimited, and drought is a recurring reality. The city’s conservation programs offer rebates for efficient fixtures, rainwater harvesting systems, and WaterWise landscaping.
- Private well owners — Test your water annually for bacteria, nitrates, and any contaminants relevant to your area. If you’re near the airport, Camp Mabry, or industrial areas, consider PFAS testing.
- Consider filtration. A carbon filter or reverse osmosis system at the point of use provides an extra layer of protection, especially during periods of elevated source water challenges.
- Understand your development’s water source. Some newer suburban communities in the Austin metro are served by small water systems or private utilities with different treatment capabilities than Austin Water.
The Bottom Line
Austin’s water story is a growth story. The Highland Lakes can supply a lot of water — but they can’t supply unlimited water, and Texas droughts are getting more severe. The city has done good work on conservation, but the fundamental challenge of serving a rapidly growing population with a climate-variable supply isn’t going away.
PFAS adds another layer of complexity, and the long-term sustainability of the Edwards Aquifer recharge zone — under pressure from suburban development — is a regional issue with generational implications.
If you’re concerned about your water quality, a certified water treatment professional can test your water and recommend solutions appropriate for your situation.