PORTLAND, Ore. — A foul odor traveled across parts of Portland metro area, leaving many to wonder where it came from. The source of the odor remains unknown, officials said in an update Wednesday afternoon.
Cowlitz County officials reported that the odor wafted down I-5. The odor was first reported around 6:30 p.m. Tuesday with calls coming in to Cowlitz County 911. According to officials, the smell reached South Kelso, Rose Valley, Kalama, Woodland, Columbia County, Clark County and eventually the Portland area.
KGW received calls and emails from viewers in the Portland area on Wednesday about the smell.
Descriptions of the odor varied from "sulfur-like" to something resembling "natural gas, propane, burning garbage, burning rubber, ammonia, and others," Cowlitz fire officials said.
Officials said their monitors are not showing any readings for gas or other substances. Officials have checked pipelines and industrial facilities in the area, and there have been no reported operational issues.
Multiple fire, environmental and utility agencies in Cowlitz, Clark and Columbia counties, as well as at the Washington state and federal level, are investigating the odor source, fire officials said.
"Some theories and investigation include ship, train, highway transportation leak; Scappoose Bio Solids; industry; pipelines; natural gas; Mt St Helens; and ground movement," fire officials said.
Wind likely pushed the odor through the metro region. According to NWS Portland, winds were predominantly out of the North and Northwest, traveling from Longview to Portland at around 5 miles per hour.
Cowlitz County officials also reached out to the Cascades Volcano Observatory, as concerns of the odor stemming from a possible eruption spread on social media. Using air quality and seismic equipment, officials have confirmed that there has been "no abnormal activities or readings" from Mount St. Helens between Tuesday night and Wednesday morning.
Their monitoring stations measure the compositions of gases coming from vents, as well as the amount of sulfur dioxide emitted from Mount St. Helens. The U.S. Geological Survey said it was "very confident" that the smell is not related to volcanoes, as the systems show no increase or change in the composition in Mount St. Helens' gases.
Scientists from the Cascades Volcano Observatory say that volcanoes typically smell like "dry, dusty" or "warm, moist" rock, as well as a smell similar to that of a struck match or rotten eggs.
Vic Leatzow, fire chief for Cowlitz County, said they're as "frustrated as everyone else" that they still can't find the source. They're currently working with the EPA to find more answers.