Strange odor reportedly wafting south along I-5 corridor toward Portland

By Staff (OPB)
Sept. 25, 2024 4:10 p.m. Updated: Sept. 25, 2024 10:39 p.m.

Cowlitz County emergency responders have found no abnormal gas readings.

Officials are trying to sniff out the cause of a strong and pungent odor that drifted south down the Interstate 5 corridor from Cowlitz County to the Portland metro area overnight. But as of Wednesday afternoon, emergency officials did not know what the smell is, or whether it could be harmful.

The smell was so strong in the Kalama area Tuesday night that the Cowlitz County Department of Emergency Management began investigating. The agency monitored the air and found no abnormal gas readings.

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The agency also reached out to manufacturers and operators of gas pipelines in Southwest Washington, and said there were no operational issues detected. Railroad operators and Washington ecology officials also did not know the cause of the smell, and emergency managers said there was no unusual Columbia River ship traffic that could have caused it either.

By late Tuesday, reports were dissipating in Washington state. But people in Portland started to file their own stench reports across multiple social media platforms after midnight.

According to the National Weather Service, meteorologists tracked winds Tuesday night that may have pushed the smell down near Vancouver. Southerly winds reported Wednesday morning likely pushed it back north.

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Larry Hembree is the emergency management director for Cowlitz County. He said people around the county have reported the odor smelling like burning rubber, natural gas, propane and ammonia, to name a few.

“Our population is pretty astute to smells … and you know could describe it pretty well,” said Hembree. “In this instance we had so many varied types of smells that it made it even more difficult to pinpoint what it might be.”

According to Hembree, the county does not have the necessary resources to properly investigate the odor — so they’ve called on multiple local, state and federal agencies to assist.

“We are working with state and federal agencies to determine who is going to take the lead on this and what their actions will be in the future,” said Hembree.

The county also checked in with the Cascades Volcano Observatory to see if the smell may be related to Mount St. Helens. According to the agency, there were no abnormal seismic activities or readings reported Tuesday night into Wednesday morning.

It’s still unclear if the smell is harmful, but Hembree says no hospitalizations have been reported.

Staff with the Cowlitz County Department of Emergency Management advise anyone who smells the odor to stay inside and keep doors and windows closed if it persists. If you have an adverse medical reaction to the smell, the agency says you should call 911.

This story may be updated.

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