Air quality unhealthy due to fire in El Dorado
Smoke and particulate matter carried by northerly winds from the 65,474 acre Caldor Fire generated unhealthy air quality Wednesday and Thursday in Tuolumne and Calaveras counties, with respite expected by the weekend.
“Things will improve,” said Bill Sandman, Deputy Tuolumne County Air Pollution Control Officer. “Yesterday wasn’t good and today is definitely not good, but the weekend, definitely better.”
As of Thursday morning, the Caldor Fire was 0% contained and near the northern border of Amador County.
Though fire growth has moderated over Wednesday night due to increased humidity, spot fires were expected to cause additional growth over Thursday afternoon.
The blaze was described as emitting “extreme fire behavior,” prompting multiple land, road and trail closures in the Eldorado National forest, northbound access to El Dorado County, and evacuation mandates near Grizzly Flat and Omo Ranch where the fire was believed to have started.
Grizzly Flat is 45 miles from Sonora as the crow flies. On roads, the route can range from approximately 75 to 111 miles and take approximately two hours.
Dave Lauchner, spokesman for the Cal Fire Team 6 incident management team assigned to the Caldor Fire, said the blaze had not yet crossed the border between El Dorado and Amador counties.
The Amador County
line runs along Highway 88 until the intersection with Omo Ranch Road and then runs along the South Fork Cosumnes River.
Cal Fire TuolumneCalaveras Unit Captain Dennis Brower responded to the unit’s media line on Thursday and noted that overhead, or supervisory, assignments and the TCU fuels crew were on the Caldor Fire.
There was no equipment assigned to the Caldor fire, Brower said.
Most of the out-of-unit resources were assigned to the Dixie Fire burning in Butte, Lassen, Plumas, and Tehama counties, which is about 1,060 square miles — more than twice the final size of the 402-square-mile Rim Fire in 2013 — and 35% contained as of Thursday.
But it was mostly the Caldor Fire causing southbound drift smoke to blanket Tuolumne and Calaveras counties on Thursday, Sandman said.
“That’s going to continue through tonight, through tomorrow morning, and then we’re going to get substantial wind change to the west/southwest beginning sometime late morning and afternoon and that should scour a lot of that smoke out,” he added.
According to Airnow, a federally partnered website which provides air quality information, Tuolumne and Calaveras counties have varied between the categories of unhealthy for sensitive groups and the more-severe unhealthy category for most of Thursday.
Purple Air, another air quality website with more specific air quality by location, showed the air quality worsening at higher elevations. In the area surrounding Pinecrest and Strawberry, air quality ranged from 170 to 217, verging into the “very unhealthy category.”
Air quality index is determined by the level of ground-level ozone, particulate matter, carbon monoxide, sulfur dioxide and nitrogen dioxide in the air.
The unhealthy air quality in the Mother Lode on Thursday was mostly a result of particulate matter produced by the wildfire.
The orange color of celestial objects like the sun and moon is a result of the light they emit (or in the case of the moon, reflect) filtering through the pollutants in the air.
According to a graphic from the National Weather Service in Sacramento, the wind direction appears to shift into the almost opposite direction by
Friday afternoon through the weekend, blanketing Lake Tahoe and Reno.
A joint release from the Tuolumne County Public Health Department and the Air Pollution Control District sought to remind the public of the hazards associated with wildfire smoke.
The release was less optimistic about air conditions the next week, saying the variance of wind direction could pollute air quality from between moderate to very unhealthy levels.
“While all people may experience varying degrees of symptoms due to exposure of smoke, the health risk to an individual depends on age, health status, and length of exposure,” the release said.
They recommended members of the public reduce their smoke exposure by limiting outdoor and even indoor activities, and closing windows and doors while inside. They said wearing a mask indoors is not considered adequate protection for smoke-related impacts, and they cautioned against smoking and the use of vacuums, fireplaces and candles.