LOWELL, Mass. — Eileen Castle’s swimming pool, one of the only ones for blocks around, was once a refuge for neighborhood children on hot summer days.

But even as temperatures soared this week, Castle, 82, said she won’t be filling the pool — not with the data center behind her house buzzing with the sound of its industrial air conditioners and its backup diesel generators belching fumes at unexpected times.

“I think about the air quality, the water, what effects it has on the kids in the area,” she said on her front stoop as children whirred past on bicycles.

Hot weather of the kind sweeping the eastern U.S. drives up electricity demand for data centers, adding to their strain on power grids and worsening air quality for surrounding areas. The impact on communities like the racially diverse Sacred Heart neighborhood in Lowell, Massachusetts underscores why the artificial intelligence industry is feeling so much heat over the fast-sprouting facilities.

Around the country, data centers have been blamed increasingly for a host of environmental ills. Some tech industry figures say the facilities have become lightning rods for concerns over broader economic and societal changes posed by the AI boom.

But on sweltering days, it’s hard not to see the effects on Castle’s neighborhood, which the state has designated as facing higher environmental and health risks because of a population that’s been historically excluded from political decision-making.

“It’s majority low-income and working family, family members who are working hard every day to just try to put food on the table,” said state Rep. Tara Hong, a Democrat who represents a heavily Cambodian American district in Lowell, a city of about 115,000 people northwest of Boston. “It’s an inclusive place there and that data center is just smack in the middle of everything.”

A heat wave is “almost the worst situation for data center operation,” said Shaolei Ren, a professor at the University of California, Riverside, who has studied AI’s environmental toll.

A data center’s racks of computer servers run hot and there are two ways to keep them running without interruption, Ren said: refrigeration-based cooling, which is energy-intensive, and evaporative cooling, which is water-intensive.

Some data centers will turn to backup diesel generators as a “preventative measure” to mitigate the likelihood of an outage, Ren said. If the grid is highly stressed, grid operators will sometimes ask data centers to turn on their generators as “the last line of defense,” Ren said.

Diesel emissions can have harmful effects on human health, even with short-term exposure. If too many diesel generators are fired up during heat waves, Ren said that could be “a disaster for the local air quality.”