The city of Alice, Texas cut ties with an unreliable surface water supply by building its own brackish groundwater desalination plant, a public-private project that made the city water-independent (Texas Living Waters, 2024). Alice isn’t an outlier. It’s a preview of where dozens of Texas and Southwest utilities are headed as surface reservoirs shrink and groundwater becomes the fallback plan.
TL;DR: Texas sits on an estimated 2.7 billion acre-feet of brackish groundwater, and the state has already permitted 98 MGD of brackish groundwater desalination capacity (Texas Living Waters; TWDB, 2024). Brackish RO systems recover 75-85% of feed water at far lower energy cost than seawater desalination, making them a practical fix for drought-stressed municipal and industrial users. Sizing one correctly starts with a TDS test, not a catalog page.
Why Is Texas Turning to Brackish Groundwater Right Now?
Texas holds an estimated 2.7 billion acre-feet of brackish groundwater statewide, a reserve large enough to outlast most reservoir-based supply plans by decades (Texas Living Waters, 2024). It matters because Texas reservoirs have been drawn down repeatedly by multi-year drought, pushing utilities to look underground instead of up.
Brackish groundwater sits below freshwater aquifers across much of West and South Texas, largely untouched because it’s too salty to drink without treatment. Reverse osmosis is what makes it usable. Unlike surface water, brackish aquifers aren’t subject to evaporation or runoff variability, so a well field paired with an RO system gives a utility a supply that doesn’t shrink every August.
The Texas Water Development Board has already responded with permitting. Statewide design capacity for brackish groundwater desalination now stands at 98 million gallons per day (MGD), with another 71 MGD permitted for brackish surface water desalination (TWDB, 2024). That’s not a pilot-scale number. It represents real, built infrastructure serving Texas communities today, and it’s still growing as more utilities apply for state funding through TWDB’s desalination programs.
Most coverage of Texas water stress focuses on reservoir levels and drought maps. The more durable story is underground: brackish aquifers give utilities a supply source that state drought monitors don’t track the same way surface reservoirs do, which is part of why the shift toward brackish RO has moved faster than public attention to it.
Texas isn’t alone in sitting on brackish reserves. Utah faces a similar setup – see AMPAC’s Brackish Water Desalination: Utah’s Untapped Water Source for how the same basic economics play out across the broader Western US, including AMPAC’s own home state.
What Does the Alice, Texas Case Study Actually Show?
Alice, Texas became water-independent through a public-private brackish groundwater desalination project, ending its reliance on a surface water source that had grown unreliable during drought cycles (Texas Living Waters, 2024). The project pairs local brackish wells with an RO treatment train sized to the city’s demand.
The lesson for other municipal and industrial buyers isn’t the specific engineering Alice used. It’s the model: a public-private partnership let a mid-sized city fund and operate desalination infrastructure it couldn’t have justified building alone, and the structure is repeatable. Smaller Texas and Southwest utilities facing the same reservoir math are watching Alice as a template, not a one-off.
Industrial users are watching too. A brackish well on-site can decouple a manufacturing plant, food processor, or data center from municipal water restrictions during drought, provided the RO system is sized correctly for the well’s actual TDS and flow characteristics. Getting that sizing step right is where most projects succeed or stall, which is the practical half of this article.
How Does Brackish Water RO Differ From Seawater RO?
Brackish water is generally classified as 1,000-10,000 ppm total dissolved solids (TDS), roughly one-tenth to one-third the salinity of seawater, and brackish RO systems typically recover 75-85% of feed water as usable permeate. Lower osmotic pressure means brackish RO runs at a fraction of the energy cost of seawater desalination.
That recovery gap is the entire economic case for brackish over seawater treatment where both are technically an option. A seawater RO system fighting roughly 35,000 ppm TDS needs high-pressure pumps, thicker membrane housings, and energy recovery devices just to force water through the membrane. A brackish system treating water in the 1,000-10,000 ppm range needs a fraction of that pressure, which lowers both capital cost and the ongoing electricity bill that dominates lifetime operating cost for any RO plant.
| Brackish Water RO | Seawater RO | |
|---|---|---|
| Feed TDS | 1,000-10,000 ppm | ~35,000 ppm |
| Typical operating pressure | 150-600 psi | 800-1,200 psi |
| Water recovery | 75-85% | 35-45% |
| Relative energy cost | Lower | Higher (pressure + energy recovery devices) |
| Typical membrane housings | 2.5″×21″, 4″×21″, 4″×40″, 8″×40″ | Thicker-walled housings rated for higher pressure |
Recovery rate isn’t fixed, though. It moves with feed water chemistry. A well with high silica or hardness will scale membranes faster at the high end of that 75-85% range, so operators often run a more conservative recovery target and add antiscalant dosing rather than push for maximum yield on day one. In practice, buyers who insist on hitting the top of the recovery range without first pilot-testing their specific well water are the ones who end up back on the phone about fouled membranes within the first year.
AMPAC’s brackish water RO membranes are sized specifically for this lower-pressure range, in 2.5″×21″, 4″×21″, 4″×40″, and 8″×40″ configurations.
How Do You Size a Brackish Water RO System?
Correct sizing starts with a water quality test, not a flow-rate guess, because TDS, hardness, silica, and iron content all determine which pretreatment and membrane configuration a brackish well actually needs. Skipping this step is the single most common reason commercial brackish RO installations underperform in year one.
Test the Feed Water First
A full water analysis should cover TDS, pH, hardness, iron, manganese, silica, and any site-specific contaminants like nitrates or sulfates common in Southwest aquifers. This isn’t optional paperwork. Membrane selection, pretreatment train design, and recovery rate targets all flow directly from what’s actually in the well, not from a generic “brackish” assumption.
Match Pretreatment to the Well
Most brackish wells need some combination of sediment filtration, antiscalant dosing, and cartridge filtration ahead of the RO membranes. Wells running high iron or manganese typically need oxidation and filtration stages first, since those minerals foul membranes fast and shorten replacement cycles if left untreated. Skimping on pretreatment to save upfront cost is the fastest way to inflate the real cost of ownership.
Set a Realistic Recovery Target
Design for 75-85% recovery as a range, not a fixed number, and let the water chemistry from step one determine where in that range the system should actually run. A well with lower scaling potential can safely push toward 85%; a harder well is often better served running closer to 75% with more frequent membrane cleaning built into the maintenance schedule.
For higher-volume municipal or industrial wells, AMPAC’s industrial RO systems scale from 6,000 to 100,000+ GPD.
Commercial and industrial buyers evaluating a brackish RO system should request membrane specs across the full size range their site needs, from 2.5-inch elements for smaller commercial applications up through 8-inch elements for high-volume municipal or industrial wells, since undersized elements are a common driver of premature membrane replacement on brackish projects.
What Should Southwest Utilities and Industrial Buyers Do Next?
Utilities and industrial water users in Texas and the broader Southwest facing tightening surface allocations have a proven, funded path available: brackish groundwater desalination, backed by 98 MGD of existing TWDB-permitted capacity and a growing track record of projects like Alice’s (TWDB, 2024). The technology isn’t experimental anymore. It’s operating today.
The next step for most buyers is the same regardless of scale: test the well, size the system to that specific water chemistry, and design pretreatment around the contaminants that test reveals. A brackish RO system built around real feed water data will outlast and outperform one sized off assumptions, whether it’s serving a 500-person town or a manufacturing plant trying to drought-proof its own supply.
Frequently Asked Questions
How much brackish groundwater does Texas actually have?
Texas holds an estimated 2.7 billion acre-feet of brackish groundwater statewide, a supply large enough to support decades of additional desalination capacity beyond what’s currently permitted (Texas Living Waters, 2024).
What TDS range counts as “brackish” water?
Brackish water generally falls between 1,000 and 10,000 ppm total dissolved solids, well below seawater’s roughly 35,000 ppm but too salty to drink or use industrially without treatment.
What recovery rate should I expect from a brackish RO system?
Most brackish water RO systems achieve 75-85% water recovery, meaning 75-85% of the feed water becomes usable permeate, with the exact figure depending on the well’s specific hardness, silica, and scaling potential.
Is brackish RO cheaper to operate than seawater desalination?
Yes. Brackish water’s lower salinity means lower osmotic pressure, so brackish RO systems require significantly less pumping energy than seawater RO, which lowers both capital and operating costs for comparable capacity.
How is Texas funding these brackish desalination projects?
The Texas Water Development Board has permitted 98 MGD of brackish groundwater desalination design capacity and 71 MGD for brackish surface water, supporting projects like Alice’s through state desalination funding programs (TWDB, 2024).
Ready to size a brackish water RO system for your municipality or facility? Request a quote from AMPAC Water Systems’ engineering team and get a configuration built around your actual well water data.