San Joaquin Valley Struggles to Lower Emissions

The San Joaquin Valley has some of the worst air pollution and particulate matter emissions in the nation, but agricultural sources are loosely regulated.

1 minute read

March 6, 2024, 12:00 PM PST

By Diana Ionescu @aworkoffiction


Two red combines harvesting corn in central California.

Terrance Emerson / Adobe Stock

California’s most intensively farmed counties don’t pass the EPA’s newest standards for particulate matter, reports Virginia Gewin in Civil Eats. Some are not even close to reaching the prior target established in 2012. “Agriculture’s contribution to PM2.5 stems from burning, soil management, and gaseous emissions from both tractors and soil,” Gewin explains.

“The San Joaquin Valley is the largest agricultural producing area in the nation; it produced  crops, livestock, and agricultural commodities worth $36.5 billion in 2022. The southern half of California’s 450-mile Central Valley is also home to some of the worst annual air pollution in the nation. Mountain ranges trap emissions from highway traffic, locomotives, municipal composting facilities, tractors, and burning.”

The article details steps the district is taking to reduce emissions and improve air quality in the regions, but critics say the regulations don’t go far enough in the agricultural sector. For example, agricultural tractors are not regulated by CARB, despite being a major source of emissions. Meanwhile, water restrictions will force farmers to leave hundreds of thousands of acres of farmland fallow, which could generate more dust.

Tuesday, March 5, 2024 in Civil Eats

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