rainbow bridge update

Before this morning, this was all I knew about the incredibly controversial proposed rainbow bridge. Today I learned that the U of A has pulled the plug on it. I thought it was a city or county thing, but the U of A was going to build what sounds like a big educational science center along the bridge, complete with a butterfly vivarium, above the freeway.

I expect I would have thought that was a stupid idea before I got sick, but having recently ridden across a bike bridge over a freeway near my parents' house, I can attest to the fact that the air directly over a freeway is dreadful, so how long do they think the butterflies would have lasted anyway?