Ask a room of Central Texas developers what stops projects and you will hear traffic, then water supply, then permitting. Those are all real. None of them is the binding constraint right now.
The binding constraint is wastewater. Not whether there is water to deliver, but whether there is capacity to treat and convey what comes back out. It is worse than the other constraints for a specific reason: power has a published queue with dated milestones, and roads have a published construction schedule, but wastewater capacity is mostly held in a utility's internal numbers and in agreements that were never designed to be read by an outsider.
A site can have frontage, clean title, by-right yield under current statute and a slot in ERCOT's interconnection process, and still not be buildable, because the lift station is full and the plant expansion has no delivery date.
Here is what that looks like in four places.
Austin: a 1977 plant and a $1.5 billion catch-up
Austin Water broke ground on the Walnut Creek Wastewater Treatment Plant expansion on April 14, 2026. The project takes the plant from 75 MGD to 100 MGD, adding 25 million gallons a day of treatment capacity, at a stated cost of $1.5 billion.
The funding stack is worth knowing because it tells you how hard this was to assemble: up to $1 billion from the EPA's WIFIA program, $59 million from the Texas Water Development Board's Clean Water State Revolving Fund, and the balance from Austin Water. The scope covers advanced treatment, nutrient reduction for algae control, replacing chlorine gas with UV disinfection, odor control, a flood wall, and modernization of aging plant.
Austin Water's own framing of why is the part to sit with. The plant was built in 1977 for a population of 320,000. It now serves over a million people. The expansion is sized against the city's projected growth to 1.5 million by 2040 and against TCEQ-mandated requirements. (Austin Water, April 14, 2026)
Now the number that matters most to a schedule, which is the number that does not exist: Austin Water did not publish a completion date. Not in the groundbreaking announcement, not anywhere we could find.
Walnut Creek's basin covers much of North and Northeast Austin. If you are underwriting there, your project sits downstream of a program with a nine-figure budget, a confirmed start and no published finish. That is not a reason to walk away. It is a reason to ask the question in writing and put the answer in the schedule rather than the assumptions tab.
There is a second signal in the same system. A wastewater sludge spill near Decker Lane and FM 969 occurred on August 17, 2026, with Austin Water responding, and a sanitary sewer overflow was reported in Northeast Austin roughly seven months before that. Austin Water runs a Pipeline Renewal program. (City of Austin news, August 18, 2026)
Conveyance is not a footnote to treatment. It fails first and it fails locally.
Dripping Springs: what a capacity fight actually costs
Dripping Springs is the clearest case study in Central Texas, because the whole sequence played out in public over a decade.
The city's South Regional Wastewater Treatment Facility on West FM 150 is permitted at 162,500 gallons per day and was described as nearing 90% of that capacity around the time its litigation resolved. Wastewater in Dripping Springs is served solely by the city, while drinking water comes from three different providers. One provider, one plant, one chokepoint.
The timeline:
- 2015: the city applied to discharge up to 995,000 GPD into Onion Creek.
- 2018: a settlement barred discharge into Onion Creek and Walnut Springs until capacity exceeds 399,000 GPD, with an agreed capacity of 822,500 GPD. The Save Our Springs Alliance did not join the settlement and kept litigating.
- 2019: TCEQ approved the 822,500 GPD permit.
- 2021: the city imposed a development moratorium on new wastewater connections.
- April 11, 2025: the Texas Supreme Court ruled for the city and TCEQ, ending a seven-year challenge.
- February 3, 2026: Council took formal steps on the expansion.
Two consequences are still landing. The expansion now needs an estimated $51.5 million in additional funding attributed to litigation delay and inflation, money that would not have been required had the plant been built on the original schedule. And a roughly 40% wastewater rate increase was approved, taking the residential base fee from $28.88 to $43.32 per month, effective this month, with further annual increases anticipated through FY2032.
The casualty worth naming: H-E-B had approval to double its local store and shelved the expansion indefinitely while the ruling was pending. We could not confirm whether that project has been revived since April 2025, so treat its status as unknown rather than dead.
That is the full cost of a wastewater constraint. Not a project that got delayed. A decade, a moratorium, a 40% rate increase paid by every existing ratepayer, a nine-figure funding gap, and an anchor tenant that walked.
San Marcos: capacity being built, on a published schedule
San Marcos is the counter-example, and it is useful precisely because the numbers are public.
The city's new Water Reclamation Facility is sized at 2 MGD initially and expandable to 8 MGD, on a $120 million total project budget, delivered as a progressive design-build. Design was 60% complete in June 2026. Construction begins in October 2026 and completion is targeted for September 2028.
Compare that to Walnut Creek: a smaller project, a smaller city, and a stated finish date. When a utility publishes a completion date you can underwrite against it. When it does not, you cannot, and the difference is not about engineering difficulty.
Hutto: the constraint written directly into the entitlement
The best single illustration we have found of how this works at the parcel level is Legacy Park in Hutto.
It is a 94-acre site, and its permitted program depends on which utility serves it. With full service, the site yields roughly 626 multifamily units plus 550,000 square feet of light industrial. If it is served by Jonah Water Special Utility District instead, the program becomes light industrial only, with the residential component eliminated to conserve water.
Same dirt. Same zoning conversation. Two completely different assets, and the variable is the utility.
That is not an edge case. It is what the constraint looks like when it is written into an approval rather than discovered in year three.
And where the answer is simply not knowable yet
Two more, offered as gaps rather than findings, because a diligence list is more useful when it is honest about its holes.
Buda holds Edwards Aquifer rights of 275 million gallons a year plus a GBRA contract for 1.5 million gallons a day from Canyon Lake. The constraint worth leading with is on the supply side for once: the Barton Springs-Edwards Aquifer Conservation District can curtail Buda's Edwards pumping by up to 40% during drought. On the wastewater side, we could not confirm the identity of Buda's provider from public sources at all. That is a research gap, and it is also a reasonable thing to be alarmed by if you are buying there.
Guadalupe County shows where the fights are heading. A data center project, Palomino Alpha, requested 500,000 gallons per day from the Crystal Clear Special Utility District, with a district board vote scheduled for August 27, 2026. The county is separately being sued over how its data center development agreements were approved, with allegations of inadequate public notice and Open Meetings Act violations. (Community Impact, July 24, 2026)
A small special utility district being asked for half a million gallons a day is the shape of the next several years of suburban entitlement in this region.
The diligence that follows
Four questions, in this order, before you spend money on entitlement.
Name the wastewater provider. Not the water provider. Not "the city." The specific entity that holds the discharge permit for the plant your sewage would reach. In the suburban rings this is genuinely hard and it is genuinely the point.
Get committed versus available capacity in writing. Available capacity is not remaining permitted capacity. Some of it is already allocated under agreements that are not recorded anywhere you would think to look.
Ask for the expansion's completion date, and treat its absence as information. A utility that publishes a date has a plan. A utility that does not may still have one, but you are now carrying that risk instead of them.
Read the rate trajectory, not just the current rate. Dripping Springs approved increases anticipated through FY2032. Utility rates are an operating expense line in every pro forma downstream of a constrained plant, and they move in one direction after a capacity fight.
None of this replaces a civil engineer or a utility availability letter. It is the screen that tells you which parcels are worth paying for those, and on this constraint, in this region, that screen is most of the work.
If you are looking at a site and cannot get a straight answer on capacity, that is the conversation we have most often. Get in touch.
This post is general information about infrastructure and development in Central Texas. It is not legal, engineering or investment advice, and it is not a representation about any specific parcel or utility. Capacity figures, rates and schedules change. Verify every date and figure against the utility or agency that issued it before relying on it.