A data center just got proposed near your neighborhood, and you have questions. That's a reasonable place to be. These are large buildings with large power connections, and nobody should have to trust a press release to understand what's coming. Here's what actually changes, phase by phase, and what's worth asking early.

The Construction Phase

This is the noisiest, most disruptive chapter, and it ends.

A typical data center building takes 12 to 24 months to construct, with larger campus projects running 24 to 36 months. During that window, you'll see heavy truck traffic: flatbeds delivering structural steel, concrete mixers, cranes, and eventually large generators and electrical gear. Peak construction employs hundreds of tradespeople on site simultaneously.

What that means for nearby roads depends entirely on the site location and how access is routed. The project's traffic study (required before zoning approval in most Arizona jurisdictions) should describe delivery routes and peak daily truck counts. Ask to see it. If truck routes run past schools or through established neighborhoods, that's a negotiating point during the permit process, not after.

Construction noise can also be significant. Earthmoving, concrete pours, and steel work create the kind of activity you'd expect from any large commercial building going up. This is temporary but worth documenting: get the project's noise mitigation plan and the hours of allowed construction activity from your city or county's planning department.

Once construction ends, the operational noise profile is different and much more manageable to address up front. We'll cover that below.

Water and Power

Two topics that come up in every community meeting, and both are worth understanding clearly.

Water. In an Active Management Area, which covers most of metro Arizona, state law requires a demonstrated 100-year assured water supply before land can be subdivided for development. The Arizona Department of Water Resources administers that requirement. How directly it binds a specific data center depends on how the project is structured, and recent court rulings have made enforcement less clear-cut. That makes the water supply behind a project a fair thing to ask about directly rather than take on faith.

Modern data centers vary significantly in how much water they use, and the range matters. The oldest designs used evaporative cooling, which draws water continuously. The Phoenix metro area effectively stopped approving those designs years ago. Newer facilities increasingly use closed-loop cooling or air-cooled systems that use far less water, and some campuses are now running on reclaimed water rather than potable supply. For a fuller picture of what data centers actually do with water, the Alliance's article What Data Centers Actually Do With Water breaks down the numbers by cooling type.

The practical question to ask: what cooling technology is this specific facility using, and what is its projected daily water draw?

Power. A data center is a large electricity customer. A 100-megawatt facility is one of the largest single loads a utility connects in a given year. That's significant, and it's also not cost-free to connect: the developer funds the transmission and substation infrastructure required to serve the site. That investment doesn't appear on residential electric bills. For a plain-language explanation of what a facility that size actually means for the local grid, see What 100MW Actually Does and Data Centers and the Grid.

Noise and Land Use

During operations, the primary noise sources are cooling equipment (fans and chillers) and backup diesel generators.

Cooling fans run continuously. Modern systems are designed to minimize this, but proximity matters. A facility 500 feet from the nearest home sounds different than one 2,000 feet away. Generator noise is typically periodic: monthly load-testing, plus runtime during actual power outages. Industrial generators can exceed 100 decibels at close range; at setback distances typically required by zoning, that attenuates significantly, but the specifics depend on acoustics, terrain, and barrier design.

Ask the developer for: the facility's projected operational noise levels at the property line, what acoustic enclosures or sound barriers are specified in the design, and what the generator testing schedule will look like.

Northern Virginia, which has handled more data center development than anywhere else in the country, has converged on recommendations that include setbacks of 500 to 1,500 feet from residential zones for larger campuses. Arizona jurisdictions are newer to this volume of development, which means the rules are still being written. Early engagement matters more here than in a market where precedent is established.

For a technical explanation of how facilities manage heat output, see Where the Heat Goes.

Taxes and Revenue

This is where data centers tend to be most misunderstood.

Arizona's Computer Data Center Program provides sales tax exemptions on qualifying equipment purchases. Those are real incentives. What they do not touch is property tax, and property tax is the mechanism that funds local schools and municipal services.

Data centers sit on relatively small footprints of land but hold extraordinary concentrations of expensive equipment and structure. Per acre, they generate among the highest property tax assessments of any commercial land use. The Alliance's analysis of this dynamic is in The Tax Base Nobody Talks About.

Research on data center economic impacts has found that they generate between $8 and $17 in local tax revenue for every dollar local governments spend on public services to support them. That said, the split between state and local tax revenue matters: some incentive structures direct more benefit to the state than to the municipality where the facility sits. Ask your planning department how the local share of property tax is calculated for this specific project.

Jobs

Be precise about what you're evaluating here, because construction jobs and operational jobs are very different things.

Construction of a large facility employs hundreds of tradespeople for one to three years: electricians, ironworkers, pipefitters, concrete workers, controls installers. These are real, well-paying jobs. They're also temporary.

Permanent operational staffing is smaller. A 100-megawatt facility typically supports 100 to 200 permanent operations roles: facilities engineers, electrical and mechanical technicians, security, controls specialists, and support staff running 24/7 shifts. These positions tend to pay above median for the region and don't require four-year degrees, which matters for workforce development. The Alliance works with Maricopa Community Colleges on exactly this pipeline.

Beyond direct employment, data centers support a vendor ecosystem of ongoing service contracts: fiber technicians, generator service providers, cooling maintenance crews, and cleaning and security contractors. These indirect jobs are real but harder to count.

The honest framing: a data center is not a factory in terms of headcount inside the building. But it contributes a tax base that can fund services for thousands of residents, and its indirect employment footprint is broader than the direct headcount suggests.

Questions to Ask Early

The most effective time to engage is during the environmental review and zoning process, before a project is approved. After approval, options narrow considerably. Here are the specific questions worth raising at a public meeting or in written comments to the planning department:

  • Water technology: What cooling system is proposed, and what is the projected daily water draw in gallons? Does it use potable water, reclaimed water, or a combination?
  • Construction traffic: What are the proposed delivery routes? What are the daily peak truck counts, and during what hours?
  • Noise: What are the projected operational noise levels at the nearest property line? What acoustic mitigation is specified in the design? What are the hours for monthly generator testing?
  • Setbacks: What is the distance from the nearest residential structure to the building and to any rooftop cooling equipment?
  • Property tax: How will this project be assessed for property tax purposes, and what does the local jurisdiction receive annually once operating?
  • Incentives: What state and local tax incentives apply, and do any of them reduce property tax revenue to the local school district?
  • Community commitments: Has the developer agreed to any local hiring provisions, noise monitoring, or community benefit arrangements?

You have every right to ask all of these. A developer who can't answer them clearly isn't ready to be approved.

The next community forum is September 17. Register at /sept-17-register.html.

Sources

Related Articles