Francis Scott Key Bridge collapse in Baltimore...

I don't think that's how it works. At least I don't think a bridge falling down was part of the calculus in judging the need for one. That said, if it's required, there obviously should be one on site. No one knows who knew what yet. I'm sure that will come out when the investigation is completed and made public.
i know at the plant i work at, if you work on or near the dock , you must wear a life jacket/vest the entire time. Or on the Gyp stack (basically a very tall lined pond). But at the height of that bridge, i am not sure someone would survive that fall.