Just a few decades ago, California’s Inland Empire billed itself as “the Orange Empire” for the citrus orchards that fueled its primary industry. Today, many of those groves are gone, and so is the nickname. The landlocked region of 4 million people an hour east of Los Angeles now sprouts more enormous warehouses (a billion square feet of them) than fruit trees.

Forty percent of the nation’s consumer goods — iPhones, sneakers, and everything available from Amazon — spend time sitting on those warehouse shelves after coming off ships at nearby ports, awaiting delivery to stores and homes. What was once a mostly rural region finds itself struggling with a high poverty rate and growing population. Residents are plagued by tremendous traffic and air pollution, which recently earned the region an “F” from the American Lung Association.

Those environmental and health concerns will get much worse, advocates say, if the city of Moreno Valley — a town of 200,000 located in the heart of the Inland Empire — builds the largest warehouse project anywhere in the country.

Tom Thornsley is a 60-year-old urban planner who moved to Moreno Valley in 1998, just as the rural-to-warehouse transformation was beginning. He thought he had chosen wisely, settling in a gray, ranch-style home that sat near a wide-open space zoned for more homes, not warehouses. “I know better than to look at dirt and not check what it would be,” he says.

But after a developer proposed a project in 2012, city officials rezoned that dirt patch next to Thornsley’s house to make it home to one of the world’s largest warehouse complexes.

Click to embiggen. Grist / Amelia Bates

The World Logistics Center, planned by a company called Highland Fairview, would be the largest such facility in the country, covering 2,610 acres — the size of 700 football fields. It would be more than 25 times bigger than the largest warehouse in the United States, a 98-acre hangar operated in Washington by the airplane manufacturer Boeing.

As a planner, Thornsley doesn’t have a problem with industrial development. He’s worked on commercial buildings since 1989. But the environmental costs of the World Logistics Center are too much for his community, he says, so he’s become a leader in the effort to stop it — an effort that might hinge on next month’s special city council election.

The World Logistics Center, which is now known locally by the acronym “WLC,” has turned Moreno Valley politics into a bloodsport. Community organizers and environmental groups have fought — in both city hall and the courtroom — to protect residents from the pollution it would cause and save protected species like peregrine falcons and California golden eagles that live in the nearby San Jacinto Wildlife Area.

Once built, warehouses don’t pollute the way that factories and power plants do. But a project the size of the WLC would be a magnet for truck traffic, spewing exhaust on 69,000 estimated daily trips in and out of the complex. In a struggling region, though, the lure of jobs has proven difficult to overcome, despite the public health and quality of life concerns.

“That’s why people are pressing so hard now,” Thornsley says, “to get somebody elected who’s not going to be, in essence, another developer’s puppet.”

Southern California’s two ports are among the deepest on the West Coast, allowing massive ships to dock at Los Angeles and Long Beach. More than $360 billion worth of goods from production centers in the Asian Pacific were offloaded there in 2014. Warehouses originally crowded around the ports, until Los Angeles could no longer contain the growth.

Demand for more space at cheaper rates pushed development farther east, and the Inland Empire became the hidden purgatory between production and consumption. Only the Philadelphia area currently has more warehouse space, but projects like the WLC would leave that East Coast hub in the dust. Over the past five years, the logistics industry has delivered a quarter of the new jobs in the region.

But the economic boom carries a heavy environmental toll: Diesel trucks zip along the Inland Empire’s roads, carrying cargo to customers and piping particulates into the air. Winds rushing in from the ocean blow added pollution from L.A. and Orange County, which accumulates in the basin bounded to the north and east by mountains.

That makes the Inland Empire one of the unhealthiest places to live in the country. Air pollution leads to higher risk of heart disease, asthma, bronchitis, cancer, and more. The South Coast Air…