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

You can often find water for a data center site without a city main, if you check the service area, rainwater, groundwater and wastewater reuse early. On our Live Show, Mike walked through those options for Texas and the approvals each one triggers, so the cooling plan and the water plan can be settled together.

Where should you start when an approved site has no obvious water?

Start with the cooling concept and the Texas PUC map. Cooling is a balance between electricity and water, and the water side decides how much power you must plan for.

Mike is not an electrical engineer, but he has talked with many data center developers who can adjust how much water their system demands.

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

The PUC regulates water and sewer providers and sets each provider's CCN, the area it must serve. Plug your site into the PUC map to see whether you sit inside or near a provider's area. That result affects every other regulated step that follows.

What on-site water sources can a Texas data center use?

Rainwater, groundwater and treated wastewater are the main on-site sources. Each one has different reliability and different approvals.

Rainwater: a data center is a large impervious site with plenty of roof. Metal roofs can drain to a capture system, and the water can be treated for the plant. Mike's projections put this at roughly 10 to 15 percent of total demand.

Groundwater: Texas has many groundwater conservation districts, and rules often tie withdrawal to the acreage you own. That is why you hear about thousand acre campuses where only about 30 acres are built. Check aquifer maps and the drilling logs the Texas Water Board keeps.

Site wastewater: the wastewater from the people running the site could be treated and reused in evaporative cooling. Mike put it at around 10 percent, but he has not seen anyone take it up because the return is small.

Mike also has a tool that scrapes this data and builds a map of the likelihood and amount of groundwater at a site. He invites readers to email him.

How reliable is each source, and what about a drought?

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

Mike likes groundwater wells and wastewater reuse as alternatives for that reason. If you go with rainwater, you need a very large holding tank to catch the big rain events through the year.

An oversized tank also lets you set up a hauling agreement with a local water provider, who can bring water in during a bad drought. On another site, the team captured rainwater and added a city tap for refill, but that was not the primary supply.

There is one more option. Mike has seen a company treat water taken from a major wastewater interceptor and feed it to evaporative cooling. The line would need to be about 12 inches or larger for a data center.

Communities may also support that approach more than a request for a large share of scarce potable water.

Which approvals does each option trigger?

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

Rainwater for employees: if more than 25 people use it, the site becomes a public water system, which is regulated by TCEQ. Check whether you are in someone's CCN first.

Groundwater: the groundwater conservation district has its own rules, plus the public water system requirements if employees drink it.

Wastewater treatment and reuse: this goes through TCEQ, with a Chapter 210 permit.

Potable water from a city: this is a permit with the city.

How do you pull the plan together quickly?

Do desktop research first, then put one water balance and one service plan in front of the whole team.

Mike said a developer can send a site and, within a day or two, we aim to report back on groundwater, rainfall capture, the nearby wastewater line and the water system's long term availability.

Ask the hard questions early. If you ramp up faster, what is the plan on the utility side? Where does the blowdown go? Does a closed loop mean no demand? Mike has heard it loses about 10 percent.

Bring the owner, cooling engineer, civil team and utility together before committing.

Watch the full episode

The full episode is on YouTube: https://www.youtube.com/watch?v=ClnYV5ZPa0g

Frequently asked questions

Can a data center get water without a city main?

Yes, in Texas there are other options, such as rainwater capture, groundwater wells and treated wastewater. Check them before you rely on a main.

What is a CCN?

A CCN is a certificate of necessity. It is the area a service provider must serve, and the PUC map shows it.

When does rainwater make a site a public water system?

If you treat rainwater for employees and more than 25 people use the site, it becomes a public water system regulated by TCEQ.

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 map to see whether you sit in or near a provider's CCN. Then look at groundwater rules and aquifer maps, rainwater capture, and any large wastewater line nearby.

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

Favor groundwater wells or wastewater reuse, which are more reliable. If you use rainwater, oversize the tank and arrange a hauling agreement with a local provider, and consider a city tap for refill.

How fast can MES screen a site's water options?

Mike said our goal is to report back within a day or two, covering groundwater, rainwater, the wastewater line and the water system.

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
• Austin Water Service Extension Requests: Who Pays for Off Site Water, Wastewater, and Reclaimed Water Improvements?

Is your data center site missing a water plan?

We screen water options for your site and map the approvals each one needs. Then we help your owner, cooling and utility teams work from one service plan.

We specialize in:

• Water supply and service planning
• Wastewater treatment and reuse design
• Site civil engineering for land development
• Utility coordination and permitting support
• Construction administration

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