Earlier quoted context omitted.
The idea is sound though. Calculate how much that particular wetland is worth ecologically and find a low-price equivalent somewhere, buy that. The Bay gets more space to sprawl their ugly single family madness and the wetlands (or more precisely the wetland equivalents) are safe too. Furthermore, it's possible to simply incrementally move the wetlands toward north by filling in a southern patch and wetland-ifying so…
So we've already destroyed 99% of wetlands in California in the last 150 years, let's play hot potato with the small patch that's left? The entire central valley was a marsh. The delta is the small part that still slightly resembles its natural state. Look at this picture of Sacramento from 1857 surrounded by ponds and wetlands: https://en.wikipedia.org/wiki/History_of_Sacramento,_Califor...
Rehabilitation of wetlands is a very important goal in itself. Now that 99% is already gone and fucked up (virtually beyond repair) ... well, it means it's almost irrelevant what happens to the remaining 1% if the other 99% will be "restored" somewhere else, then that 1% can be "moved" too.
Not to mention that it the fugly plain of endless mansions sitting where the wetlands were would be replaced with a few high rises, there would be ample space to recultivate a big chunk of it.