See how Sacramento’s polluted air compares to the smokiest days in last dozen years

Sacramento County’s gray, ash-filled air was among the worst air quality the region has seen in the last dozen years — but not as bad as the smoke from 2018’s Camp Fire, federal data show.

Wildfire smoke often produces high concentrations of PM2.5, very fine particulate matter that can harm the heart and lungs. Local air districts track the amount of PM2.5 in the region and use their measurements to create an Air Quality Index. An Air Quality index over 150 is considered unhealthy — a “code red” day. An Air Quality Index over 200 is considered very unhealthy.

Since 2008, the index has reached “code red” PM2.5 levels 28 times in Sacramento County, according to U.S. Environmental Protection Agency data. Most of those bad air days were due to wildfires, though wood-burning stoves and fireplaces can contribute to unhealthy days in the winter.

Camp Fire

The longest recent run of bad air quality in Sacramento County was during the 2018 Camp Fire. During that crisis, the county experienced 11 consecutive “code red” days, leading local officials to shut down many schools and colleges.

On Nov. 15, 2018, Sacramento had the most polluted air on the planet, according to Berkeley Earth, which tracks air pollution worldwide. That day PM2.5 AQI levels hit 314 in downtown Sacramento, their highest point since at least 1999.

The Camp Fire was responsible for all 10 of the smokiest days in Sacramento since 2008.

2008 lightning fires

During the summer of 2008, a large number of fires were sparked by dry thunderstorms. These fires included the Lime Complex in Trinity County, which eventually burned about 63,000 acres; the Iron Complex in Trinity County, which eventually burned about 83,000 acres; and the American River Complex in Placer County, which eventually burned 21,000 acres.

All told, wildfires that started between June 20 and June 22 of 2018 would burn close to a million acres — and send a lot of smoke over Sacramento.

Later, a wildfire ripped through the community of Concow in eastern Butte County in early July, destroying more than 200 homes and threatened the nearby town of Paradise — which would burn in the Camp Fire a decade later — before firefighters brought it under control.

On July 10, 2008, smoke from that and other fires created unhealthy air throughout Sacramento County.

2020 lightning fires

The worst air quality seen in Sacramento County during this latest batch of wildfire occurred on Saturday, when the AQI was measured at 174. That’s worse than any AQI measurement during the 2008 lightning wildfires. It’s about as bad as the air quality seen toward the end of the Camp Fire crisis.

The Sacramento Metropolitan Air Quality District is forecasting continued hazy skies and unhealthy air for the rest of the week.

This story was originally published August 24, 2020 at 9:24 AM.