Changes focus on improving efficiency and delivering timely, transparent permit decisions.
Learn about Solano County - its climate, potential air pollution concerns, and current air quality. You can also view upcoming Air District events in Solano County and read about local efforts to improve air quality.
Changes focus on improving efficiency and delivering timely, transparent permit decisions.
The Air District has fined Chemtrade West US LLC $160,000 for air quality violations at its sulfuric acid manufacturing plant in Richmond, which is connected to the Chevron Richmond refinery. Chemtrade supplies various chemical products to industry, including sulfuric acid, which is a byproduct of refining crude oil.
The Air District is lifting an air quality advisory for wildfire smoke that was originally scheduled to last through tomorrow, Wednesday, August 27.
The Air District has announced a $13.3 million grant to the San Mateo County Transit District toward the installation of new high-capacity electric bus charging infrastructure at its San Carlos facility. This SamTrans project will help accelerate the transition of the SamTrans bus fleet to zero-emission technology and improve air quality in communities most affected by air pollution.
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Solano County is bordered by Napa and Yolo counties to the north, Sacramento County to the east, and San Pablo Bay to the south. The Air District only has jurisdiction over the southwestern portion of the county, which includes Vallejo and Fairfield. One Solano County representative sits on the Air District’s Board of Directors.
During summer and fall months, high pressure offshore, coupled with thermal low pressure in the Central Valley, draws marine air eastward through the Carquinez Strait almost daily. Temperatures along the coast and inland tend to remain moderate. Winter temperatures range from cool overnight to moderate during the day, while summer temperatures range from moderate overnight to warm during the day. Afternoon westerly winds are common in the southern portion of the county, along the Carquinez Strait. Annual rainfall totals range from 13 inches near the coast to 22 inches inland in Fairfield.
Interactive Air Monitoring Stations Map
Ozone and fine particle pollution, or PM2.5, are the major regional air pollutants of concern in the San Francisco Bay Area. Ozone is primarily a problem in the summer, and fine particle pollution in the winter.
In summer, most of Solano County is exposed to prevailing westerly winds through the Carquinez Strait, which mixes and reduces ozone levels by drawing cooler, marine air from the Pacific Ocean and San Pablo Bay eastward. However, when the marine flow is weak or nonexistent, ozone levels may exceed health standards on a few days each year, mainly east of Suisun City.
In Solano County, PM2.5 concentrations can become elevated enough to exceed health standards during the winter when air pollution is transported from the Central Valley due to prevailing easterly winds. Local residential wood burning can also cause elevated particulate levels on cold, calm evenings during winter.
Last Updated: 4/21/2017