Data Center Water Supply in Texas: How to Build a Water Plan That Holds Up

What should the plan document actually contain?

One sheet per phase with five lines: demand, proven sources, required approvals, operating limits and the owner of the next decision.

A plan is a record, not a narrative. Anyone on the team, from the owner to the utility, should be able to read the sheet and see what is proven, what is assumed and who closes each gap. When a phase changes, the sheet changes with it.

The rest of this post is how to fill in each line so it survives review by a utility, a lender or a state agency asking questions.

Why split demand into three lines?

Because each demand has different quality, flow and reliability needs, and a source that fits one may be useless for another.

• Drinking water covers people and fixtures: drinking, handwashing and anything that touches food. Toilet and urinal flushing does not need drinking water; it is a Type I reclaimed water use under 30 TAC §210.32.
• Cooling and process water is makeup, losses and discharge, and each changes with the operating case. Water cooling can cut electrical demand compared with air cooling, so this line moves when the mechanical design moves.
• Fire protection is a required flow, a duration, a reserve and a refill rate. The tank may sit on site or belong to the local water provider.

Write each line for each operating case: normal, peak summer and the worst credible day. A single annual number hides the day that matters.

How do you grade the evidence behind each source?

By what the document behind it can support. A phone call, a feasibility report and a signed service agreement each do a different job, and only the agreement supports a schedule.

A service map is not a reservation. A site can sit inside a provider's certificated area and still have no capacity commitment. For utility water, the steps run in order:

1. Confirm service authority, source rights and access.
2. Submit phased demand and test delivery capacity.
3. Resolve upgrades, cost allocation and conditions.
4. Document the authorized commitment and its milestones.

Many small systems are underbuilt for a large new load, so expect improvements and some back and forth. Asking for day one capacity first, then phasing the rest, keeps the request realistic. For utilities, utility and municipal planning support starts with the evidence behind any capacity credit.

Grade groundwater the same way. A shared well is proven only when it has source rights, land and access rights, tested yield and quality under drought assumptions, and a long-term operator. In most of Texas a groundwater conservation district also sets permit and production limits under Water Code Chapter 36 (opens in a new tab). If any step falls short, stop or redesign before counting the well.

Which Texas rule applies to each alternative source?

It depends on where the water starts. Classify the source first, then check its rule path in 30 TAC Chapter 210 (opens in a new tab).

• Rainwater and air-conditioner condensate are "alternative onsite water" (§210.82), and Subchapter F covers their use at commercial and industrial facilities (§210.81).
• Domestic reclaimed water from a municipal plant follows Subchapters A to C.
• Industrial reclaimed water follows Subchapter E, the 210E path.
• Commingled water, industrial wastewater with any domestic wastewater in it (§210.52(3)), is subject to the domestic reclaimed water rules (§210.56(a)(1)), though it can still get a Level II authorization (§210.53(b)(2)).

Treat this as a screen and confirm the path with TCEQ early. For industrial reuse, identify every stream feeding it, confirm the eligible use and location, then prove usable flow, storage and a lawful fallback for off-spec water.

How do you close the water balance?

Count each source once, on the same time basis, against a named demand.

Daily beats annual. A large roof may collect enough rain over a typical year, yet cooling demand peaks in a dry stretch and the tank empties. Model capture, demand and storage day by day through dry periods, then define the backup or the curtailment.

The balance also has to carry the losses people forget: evaporation, blowdown, treatment reject and the change in storage. Match each alternative source to the specific demand it serves, so rainwater is not counted against drinking water and cooling at once.

Will the backup fail when the primary does?

It can, if both depend on the same thing. A second supplier, a second well or stored rainwater may share an aquifer, a power feed or the same dry weather.

For every backup, write down four things:

1. The common failures it shares with the primary.
2. The usable storage, not the nameplate volume.
3. The delivery rights, including any hauling contract.
4. The curtailment trigger, who acts on it and which loads can stop.

Water hauling contracts are a fallback worth pricing early, in case production from the planned sources falls short.

Who owns the system when the plan fails?

Name one owner for each source and one for the whole system. A shared well, a reuse line or an on-site plant needs an operator, an allocation rule, funding and maintenance that outlast the construction contract.

Developers can build that ownership into early site civil and land development work, while easements and agreements are still easy to write.

A note on limits: this is general engineering education based on Texas rules as published in October 2026. State policy on data centers is moving, so confirm each rule path, your site's data and any agreement with your engineer, counsel and the agencies involved.

Frequently asked questions

Is a utility service area map enough to count on water?

No. It needs a written capacity commitment, or an approved path with its conditions resolved, before it supports a schedule.

Why is annual rainwater yield misleading?

Cooling demand can peak in a dry stretch when the tank is empty. Model capture, demand and storage day by day through dry periods.

Which Chapter 210 subchapter covers rainwater and condensate?

Subchapter F, which covers graywater and alternative onsite water. Rainwater and air-conditioner condensate are in the §210.82 definition of alternative onsite water.

I'm a developer in Texas looking at a rural site with no water line out front and a nearby well. How do I know if the well can support a data center?

Audit well records and geology, confirm rights and the groundwater district's rules, then test the permitted source for yield and quality. Stop or redesign if the evidence does not support the supply.

I run a small water system in Texas and a developer wants a large capacity commitment. What evidence should I ask for before agreeing?

Ask for phased demand, tested delivery capacity, and clear terms on upgrades, cost allocation and conditions. Document the commitment and milestones, and know who owns the system if the plan fails.

Related resources

• Texas Data Center Water Supply: What Developers Are Getting Wrong Before They Break Ground
• Data Center Water Supply in Texas: How to Find More Water Before You Rely on Electricity
• Texas Chapter 210 Reclaimed Water Permits: Type I vs. Type II and When You Need One
• Fire Flow Analysis: Engineering Solutions for Municipal Water Distribution Systems

Is your data center water plan proven in writing?

We help developers and utilities test each source, close the water balance and document demand, approvals and ownership for every phase. Talk with an engineer about your water plan.

We specialize in:

• Water supply and wastewater due diligence
• Chapter 210 and 210E reclaimed water authorizations
• Fire flow analysis
• Water and wastewater design for industrial sites
• Utility and municipal planning support
• Site civil engineering for land development

Modern Engineering Solutions, McKinney, Texas. Contact: (214) 833-6748 or mod-eng.com