Data Center Water Supply in Texas: How to Find More Water Before You Rely on Electricity

Why does the water search come before the cooling decision?

Because cooling trades water for electricity, and the water you can find sets how much power you have to plan for.

Evaporative cooling uses water to save power. Air-cooled and closed-loop designs use far less water, but they draw more electricity. Many developers can adjust their cooling system's water demand, so the water inventory should reach the mechanical engineer before the design is locked.

Many people assume a water main is the only way to get water. In Texas there are other options, and you can screen them from a desk.

Is your site inside someone's certificated service area?

Check that first, because it shapes every regulated step that follows.

The Public Utility Commission of Texas issues a Certificate of Convenience and Necessity (CCN) that gives a retail water or sewer utility its service area. Put the site into the PUC's Water and Sewer CCN Viewer (opens in a new tab) to see whether it sits inside or near a provider's area.

Inside a CCN, the holder is part of the conversation even if you plan to serve yourself. Our post on CCN territory disputes in Collin County shows how that plays out.

What other water sources can a Texas data center use?

Five, in roughly the order to check them.

• Rainwater. A data center is a large impervious site with a lot of roof. Metal roofs can drain to a capture system, and the water can be treated for the cooling plant.
• Groundwater. Much of Texas is covered by groundwater conservation districts, and under Water Code §36.116(a)(2) (opens in a new tab) a district may limit production based on acreage or tract size. That is one reason large campuses hold far more land than they build on.
• Treated site wastewater. Wastewater from the people running the site can be treated and reused in evaporative cooling. The volume is small, so few owners take it up.
• A sewer interceptor. Water taken from a large municipal wastewater line can be treated on site and fed to evaporative cooling. The line has to be big enough to carry the flow you need.
• Hauled water. A hauling agreement with a local water provider can refill storage during a drought.

For groundwater, start with the aquifer maps and the Texas Water Development Board's Submitted Drillers Report database (opens in a new tab), which shows what nearby wells hit.

How reliable is each source in a drought?

Deep groundwater is usually the most reliable. Rainwater and site wastewater vary, so they need backup.

Rainwater needs a very large tank. The tank has to catch the big storms and carry the plant through the dry months between them. An oversized tank also gives a hauler somewhere to deliver during a bad drought.

A city tap can refill storage too, without being the primary supply. Treat any refill or hauling arrangement as a contract to document, not an assumption.

The interceptor option has a community angle. Asking to cool with treated wastewater may get more local support than asking for a large share of scarce drinking water.

Which approvals does each option trigger?

Each source runs through a different agency, so map them before you design.

• Drinking water for staff. A system becomes a public water system when it has at least 15 service connections or serves at least 25 individuals at least 60 days a year, and employees count (30 TAC §290.38 (opens in a new tab)). TCEQ's Chapter 290 rules then apply, whether the source is rainwater or a well.
• Groundwater. The district's own permit, spacing and production rules, plus the public water system rules if staff drink it.
• Rainwater and condensate for cooling. These are alternative onsite water under 30 TAC Chapter 210, Subchapter F.
• Treated wastewater, from the site or an interceptor. TCEQ authorization for the treatment and for the reuse under Chapter 210, plus the sewer owner's agreement for an interceptor.
• City water. A service or extension agreement with the city or utility.

Confirm each path with the agency early. Rule paths for reuse depend on where the water starts.

What questions should the whole team answer early?

The ones that change demand or disposal after the land is bought.

1. If the campus ramps up faster than planned, what is the plan on the utility side?
2. Where does the cooling tower blowdown go?
3. Does the closed-loop design still need makeup water for losses, and how much?
4. Which source carries the plant when the primary one stops?

Put one water balance and one service plan in front of the owner, the cooling engineer, the civil team and the utility before anyone commits. Our water and wastewater due diligence work starts there.

A note on limits: this is general engineering education based on Texas rules as published in October 2026. Each source needs site data, and each approval path should be confirmed with the agency, the district and your counsel.

Frequently asked questions

Can a data center get water without a city main?

Often, yes. Rainwater capture, groundwater wells, treated wastewater and hauled water are all options in Texas. Check them before you rely on a main or on air cooling.

What is a CCN?

A Certificate of Convenience and Necessity, issued by the PUC. It gives a retail water or sewer utility its service area, and the PUC's viewer maps it.

When does on-site drinking water make a site a public water system?

When it has at least 15 service connections or serves at least 25 individuals at least 60 days a year. People who work at the site count.

I'm a developer with an approved data center site in Texas and no water main nearby. What should I check first?

Check the PUC's CCN viewer to see whether you sit in or near a provider's area. Then look at the groundwater district's rules and nearby well records, rainwater capture, and any large wastewater line close by.

I'm planning evaporative cooling at a Texas campus and worry about drought. How should I back up my water supply?

Favor a groundwater well or wastewater reuse as the steadier sources. If you use rainwater, oversize the tank, arrange a hauling agreement with a local provider, and consider a city tap for refill.

Related resources

• Texas Data Center Water Supply: What Developers Are Getting Wrong Before They Break Ground
• Data Center Water Supply in Texas: How to Build a Water Plan That Holds Up
• Water Certainty Before Site Commitment: A Texas Data Center Developer's Guide
• Can treated wastewater cool a Texas data center instead of drinking water?

Is your data center site missing a water source?

We screen the water options for your site, map the approvals each one needs and help your owner, cooling and utility teams work from one service plan. Talk with an engineer about your site.

We specialize in:

• Water supply and wastewater due diligence
• Desktop groundwater screening
• Wastewater treatment and reuse design
• Chapter 210 reclaimed water authorizations
• Utility coordination and permitting support
• Site civil engineering for land development

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