Furious residents packing city-council meetings have become a familiar scene as proposals for data centers spark backlash in towns across America. But in Gilroy, Calif., known as the world’s garlic capital, there’s a twist: The $2 billion facility that residents are railing against is already being built.

“Many if not most residents first learned about this project after construction had already begun,” Coleen Crew, an elementary-school teacher, told the council at a recent meeting.

There were no public meetings or votes before a lone city staffer gave Amazon the green light last July to build a 438,500-square-foot data center on 56 acres of farmland 30 miles south of San Jose.