If Los Angeles, notorious for the clouds of smog hanging on the horizon, can consistently make progress in cleaning up its air, why does the Central Valley lag behind?
Part of the blame lies with the region’s topography. Ringed by several mountain ranges, including the Cascade, Sierra Nevada, and California Coastal ranges, the 18,000-square mile valley is a flat basin. Without any breezes from the coast to mix the bad air out, like the Delta breeze enjoyed in Sacramento, San Joaquin, Stanislaus and Merced counties, the dirty, smoggy air gets trapped in the southern valley.
The Central Valley is also prone to ozone inversions, where warmer air floats above cooler air to form a lid that keeps polluted air swirling around like dirty water in a toilet bowl. Prolonged drought and intense heat have also created the perfect conditions for wildfires, which contribute to both PM2.5 pollution and create the raw ingredients of ozone.
When choosing who to blame for air quality woes, many point the finger at agriculture. At first glance, this seems reasonable. Anyone who has traveled around the Central Valley has seen tractors stirring up clouds of dust along the highways and back roads as they plow the fields, and those in Kern County are intimately familiar with the woes of nut harvest.
While financially lucrative for farmers, nut harvest is notoriously bad for air quality. For two or three months out of the year, pillars of dust billow from orchards and coat nearby trees, cars and houses in a fine brown sheet, contributing to PM10 and ground-level ozone pollution.
However, agricultural activities account for surprisingly little air pollution and greenhouse gas emissions. While they are responsible for 59 percent of carbon dioxide emissions and 65 percent of methane emissions from soils management and crop and fertilizer residue, agriculture contributes only 8 percent of total statewide greenhouse gas emissions, according to data from the state Air Resources Control Board.
Transportation and industrial activity are by far the biggest offenders, weighing in at 37 percent and 24 percent, respectively. Population growth is partly to blame. Already home to 6.5 million, the Central Valley is one of the fastest growing regions in the nation, meaning more cars and trucks on the road and, of course, more traffic congestion.
This also means greater freight traffic. Sixty-seven percent of goods shipped annually from California are by truck and 20 percent by parcel services. Though trucks ship out $1.3 trillion in goods and bring in another $1.3 million each year, they account for almost half of the state’s nitrous oxide and diesel particulate matter emissions.
But efforts to clean up the Central Valley’s dirty air have not failed for lack of trying. According to a 2016 PowerPoint prepared by the U.S. Department of Agriculture’s Air Quality Task Force, the San Joaquin Valley Air Pollution Control District has the toughest regulations on both large and small businesses, farms and dairies, cars and trucks, and consumer products.
Businesses in the area are also doing their part to help. Michael Gutierrez, director of corporate communications with The Wonderful Company, told Courthouse News in an email that the company “is committed to finding new, environmentally safe alternatives to traditional harvesting methods, particularly in reducing dust and improving Central Valley air quality.”
The company not only helped develop a nut-harvesting machine that reduces dust particles by up to 70 percent, they no longer burn tree waste. Instead, they grind it up and send some of the bio-mass to a cogeneration plant “where it is used to generate energy and incorporate the balance into the soils to increase organic matter and improve soil health,” Gutierrez wrote.
Lauren Castillon, senior manager with Bolthouse Farms, said the company takes the welfare of the community and the environment very seriously.
“[T]hat’s why we make efforts to help minimize pollution by adopting new practices and technologies, like converting to electric irrigation and exploring windbreaks surrounding our fields. Additionally, we participate in emission reduction efforts, such as California’s Air Resource Board cap-and-trade program, requiring that participants decrease measurable emissions year over year to aid in reducing the state’s greenhouse gas emissions to 1990 levels by 2020,” she wrote.
Business in the San Joaquin Valley spend approximately $40 billion a year on clean air, while the region’s air quality district spends over $1 billion of annual public and private investment on incentive-based reductions. Though these efforts have reduced emissions by over 80 percent, the district needs to achieve another 90 percent reduction to meet new standards, according to the PowerPoint.
Failing to meet these standards can lead to costly federal sanctions, including loss of highway funds. It may also force the district to take drastic measures, like shutting down all stationary sources of pollution, agriculture, passenger cars and heavy-duty trucks to reach attainment of federal standards.
These problems aside, the San Joaquin Valley’s air quality has steadily improved over the last 15 years. These advances are thanks in part to the district’s adoption of new rules to reduce emissions from stationary sources, cooperation with transportation agencies to develop transportation control measures, promotion of state and federal clean-vehicle and clean-fuel programs, and the development of programs like the Real-time Air Quality Network and Air Quality Flag program, which educate the public and allow them to make informed decisions based on air quality, according to the district’s FAQ webpage.
To keep this momentum going, Congress must keep the Clean Air Act intact and enforced, retain clean vehicle emissions standards, reduce emissions from new and existing oil and gas operations, and support tough air pollution control standards rather than retreat on the issue, the American Lung Association says in its report.
“The cuts being proposed at the EPA will not only cripple the EPA’s enforcement of the Clean Air Act, it will also have a really negative impact on local air pollution cleanup efforts – the president’s budget includes half a billion dollars in cuts to state and local grants. That’s money they use to clean the air,” Paul Billings, the senior vice president of advocacy at the American Lung Association, told the online news site Quartz.
“Losing those dollars means that not only will the federal cop not be on the beat, it means that state and local agencies will be hamstrung as well. Which means we may lose some of the progress we saw in this report.”
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