LONGMONT, Colo. — Longmont is drawing a line against hyperscale data centers, passing an ordinance Tuesday night that sets limits on facility energy consumption to protect the city's power grid, water supply, and neighborhoods from impacts seen elsewhere across the country.

In a 6-1 vote, Longmont City Council passed a city ordinance capping data center energy usage at either 5% of the region's grid capacity or 100 megawatts, whichever is lower. City staff said 100 megawatts is enough to power between 10,000 to 30,000 homes on a hot summer day.

▶️WATCH: Maggie Bryan breaks down this new development in her Tuesday evening report below.

Longmont bans hyperscale data centers amid concerns about energy and water use

Longmont joins a growing list of Colorado communities, including Denver and Jefferson County, that have passed measures limiting construction or operations of data centers after community concerns about their strain on local resources and impacts on neighbors. Diana Chavez, a Longmont resident, said she's concerned with the amount of water used by large-scale facilities.

"One of my big concerns is that they just seem to be full steam ahead... regardless of the consequences, it seems like. And the consequences concern me, because they're massive, so it's acres and acres of land that is gone," Chavez said.

The Environmental and Energy Study Institute said large data centers can use up to 5 million gallons of water per day, similar to the water use of a town with 10,000 to 50,000 people.

Longmont City Councilmember Matthew Popkin, who brought the ordinance forward, said the city needs guardrails in place to determine which kinds of data centers make sense for Longmont. He said the city is already home to smaller data centers that are involved in emergency services, hospitals, and critical infrastructure. Popkin said data centers are welcome if they serve a purpose for the local community and do not put a strain on resources.

"What we have seen across the country are data centers popping up in a whole range of communities at a whole range of different shapes and sizes and scales, and so I wanted us to get ahead of that, kind of set the terms for what makes sense for Longmont and what doesn't make sense for Longmont," Popkin said.

Longmont City Councilmember Diane Crist was the only vote against the ordinance. During the meeting, Crist said she wanted to table the measure to gather more specific information about resources used by data centers, and called the ordinance "half-baked."

The Jefferson County Board of Commissioners voted on May 19 to temporarily stop the development of future data centers within county limits until March 2027, arguing they need time to weigh the environmental impact with potential economic benefits in the midst of Colorado’s historic drought.

In the same week, Denver City Council unanimously approved a one-year moratorium on new data center construction, with plans to form a task force to study the impacts of data centers and develop stronger regulations surrounding the facilities.