It is that time of year when wildfire season is again upon us.

The extreme drought experienced in the San Joaquin Valley over the past few years coupled with an increase in tree mortality in the Sierras due to an insect infestation has led to an excessive buildup of combustible materials. This puts the valley at risk for potential wildfires, which are ignited mostly by lightning strikes.

Air pollution generated from wildfires is enormous and often exceeds the total industrial and mobile source emissions in the San Joaquin Valley. When such a fire erupts, it overwhelms all control measures, resulting in periods of excessively high particulate matter and ozone concentrations. There are many negative effects associated with wood smoke. Particulate matter (PM2.5) found in smoke can cause serious health impacts, especially to individuals with existing respiratory conditions, elderly people and small children.

When wildfires occur, the San Joaquin Valley Air Pollution Control District steps up efforts to protect the public. When smoke is affecting residents, the district works with public land managers to see if more firefighting resources can be placed in those areas to minimize smoke impacts. Through the collaboration of multiple agencies, the district is able to give out accurate and timely information to the public.

Valley residents can safeguard their health and stay up-to-date through the district’s wildfire page, This webpage keeps valley residents in tune with local wildfires that are affecting air quality in the valley by providing information from the fire agency overseeing the fire, linking to the district’s Real-time Air Advisory Network, explaining steps to limit your exposure to smoke and offering a short video about wildfire and air quality. One will also find the latest wildfire press releases issued by the district.

The two agencies that can oversee a wildfire in our area are Cal Fire and the Department of United States Forestry. The wildfire page provides a direct link to these agencies online tools, InciWeb or Cal Fire, which will give valley residents all the pertinent information and stats pertaining to a particular fire. Those webpages are another resource for valley residents to stay connected with local fires that could potentially affect one’s health. District staff also collaborates with the California Office of Emergency Response and public land managers to deploy portable air monitoring equipment in areas impacted by smoke.

The wildfire page also contains information on the district’s state of the art Real-Time Air Advisory Network system, where valley residents can check the air quality data in the district’s network of air monitors to see if PM 2.5 is elevated in their area. RAAN notifications are particularly important when wildfire plumes enter the valley and elevate ozone and PM2.5 pollution to dangerous levels.

Schools and the public use these RAAN notifications in order to curtail outdoor activities during high pollution/smoke episodes. Be aware however, that the RAAN system is designed to detect fine particulates that exist in smoke. On occasion, larger ash particles may be too large to be detected by our system. Therefore, an area may be experiencing ash impacts from potential fires yet it may not be reflected in the system.

If you can smell smoke or see ash, that is an indication that you should be treating air quality conditions as “unhealthy” and remain indoors.

For more information about the air district, call a regional office in Bakersfield, 661-392-5500; Fresno, 559-230-6000; or Modesto, 209-557-6400.

Cassandra Melching is an outreach and communications representative with the San Joaquin Valley Air Pollution Control District.