As coronavirus cases spread in Oregon, TriMet saw significant ridership declines, and transit officials say they are prepared for more “big drops” during the coming weeks following a state ban on large events.

According to five weeks of ridership figures provided to The Oregonian/OregonLive, the transit agency saw a notable decline in ridership in the most recent week of data available, which ended March 6, when compared to the previous month.

On March 6, one week to the day after the state’s first presumptive case of the coronavirus was detected, TriMet saw trips decline 13% compared to the previous week. When compared with the average weekday from the previous month of trip data, every day of the week saw ridership declines. Monday and Friday, in particular, saw the steepest dips.

The transit agency isn’t alone in seeing people cancelling work or travel plans. This week, Port of Portland officials estimated air travel had declined 10%.

Roberta Altstadt, a TriMet spokeswoman, said with the Portland Trail Blazers’ and Timbers’ seasons now suspended, along with Portland State University and other large institutions urging remote learning or working, ridership will continue to go down.

“We will see a big drop,” she said.

That will translate to less revenue for the tri-county transit agency, which registers an average of 300,000 transit trips every day. “It is important to note that while the revenue TriMet earns from fares covers more than $124 million in current annual operating costs, or 17% of our operating expenses,” Altstadt said in an email, “TriMet’s concern at this time is the health and wellbeing of our riders, our employees and our community as a whole.”

During a Thursday morning news conference, state health officials said they were working with TriMet to keep people three feet apart on public transit, a measure intended to reduce the risk of contracting the novel coronavirus.

Health officials didn’t offer any specific guidelines on what that looks like in practice. Altstadt said that anyone who has ever been on a full bus or train knows that level of distancing “may not be possible.”

That could change if fewer people are riding the rails or buses. “With more people working remotely, there is more space on buses and trains, so riders may be able to space themselves out,” she said.

In the meantime, she said, the agency will “continue to encourage riders to follow the direction” of federal, state and local health officials, “including when possible to keep space between them and others.

The transit agency continues to disinfect all “touch points” on trains and buses used across Washington, Clackamas and Multnomah counties every day. The cleaning regimen applies to paratransit vehicles and the agency’s commuter rail line between Wilsonville and Beaverton as well.

Altstadt reminded riders that surfaces are only clean until someone sneezes, coughs or touches them. Riders should stay home if they are feeling sick, she said.

-- Andrew Theen; atheen@oregonian.com; 503-294-4026; @andrewtheen

Staff writer Mike Rogoway contributed to this story

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