[jeffers]

This site says Lake P. causeway lost 17 spans and was open 2.5 weeks after Katrina.

https://www.worldatlas.com/places/lake-pontchartrain-causeway.html

This link says the US 90 Bay St. Louis bridge had to be replaced, which took 21 months. Pictures indicate it lost a lot more than 17 spans, and another site indicates there were structural problems with the piers.

https://en.wikipedia.org/wiki/St._Louis_Bay_Bridge

[blam]

"This link says the US 90 Bay St. Louis bridge had to be replaced, which took 21 months."

That's a completely new, higher bridge.