Burnside Bridge Earthquake Readiness Project

[eric cantona]

Originally Posted by Jakz

Construction inflation--generally tariffs, overall inflation, and higher wages--is around 100% over the last decade, if the Mortenson index is to be believed. Even factoring that in, this bridge is still two or three times more expensive on a per-square-foot basis.

Both the Tillikum and South Park bridges were designed to modern codes, including seismic loading, so costs should be fairly comparable. And in general the added cost of designing a new structure to resist earthquakes is small, in the 5-10 percent range (unlike retrofits which are hideously expensive). I'm sure the immediate usage designation adds some cost, but again I don't think it would be a major cost driver.

w.r.t the IBR...yeah, the $7.5 billion estimate is from 2022, the same year of the $900 million estimate for this bridge. If costs are doubling...that project could be headed towards a ludicrous $15B.

This is not being designed to modern seismic codes. It is being designed to remain standing and USEABLE after the inevitable Cascadia mega earthquake. It is being called a "lifeline route". It will be the first such bridge in Portland.