There are new bridges that should stay up and offer way across the river after quake.
Lots of smaller bridges are going to come down. I don’t know why there isn’t more focus on them. They should be easier to retrofit. And at least have one in each area that will stay up to keep city connected. For example, I live near hospital but it is on other side of freeway and have no idea if will be reachable.
Fremont bridge was the first earthquake-rated design put in. The Marquam has seen seismic upgrades, the Tilikum is brand new and should be fine, as is the new Sellwood Bridge replacement.
Every other bridge has been touched since the 80s/90s, but I don't have a lot of faith that, say, the Steel or Hawthorne will stay up.
The Fremont bridge should stay up. But the approaches will collapse making it unusable. The Tilikum and Sellwood bridge are the only new ones designed to survive. They have started working on replacing the Burnside bridge. The lift and draw bridges would be destroyed.
Everyone focuses on the big bridges, which won’t do well in Portland, but no one thinks about the small bridges across creek crossings in neighborhoods and surface streets. I have to cross 3 creeks before I even get to the highway. I’ll be walking/wading out.
Lots of smaller bridges are going to come down. I don’t know why there isn’t more focus on them. They should be easier to retrofit. And at least have one in each area that will stay up to keep city connected. For example, I live near hospital but it is on other side of freeway and have no idea if will be reachable.