North South Western States freight trains are being diverted over Donner Pass in California

The damage is affecting all UP's rail operations between Redding and Eugene, Tysver said. Freight trains are being diverted over Donner Pass.

Scheduled trains for the Amtrak Coast Starlight, which also runs along the route, have been canceled at stops north of Sacramento until at least mid-July.

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https://www.statesmanjournal.com/story/news/2021/07/07/union-pacific-closes-siskiyou-line-until-lava-fire-damage-repaired/7896275002/

This must mean that freight Trains are rerouting through Nevada? maybe from Eugene but all Amtrak riders aren't riding trains from Eugene to Redding. So, likely they are putting them on buses to Redding at Eugene, Oregon? Train lines often do this in emergencies like this when train lines get closed by falling rocks or snow at times also or when tracks get damaged by one thing or another.