As long as that bridge is closed, it infinately often
It may not happen often that a bridge is closed, however, if a bridge stays closed, it would be nice to be aware of it prior to making my trip so that I could plan accordingly.
A section like that would not have much 'activity', but then a closed bridge stays closed. It shows no activity, but if it stays closed, people need to be aware of it.
I sure could have appreciated a warning on the case of the SR213/Clackamas River Bridge prior to my trip so that I could have diverted to Oregon City before decending that long hill only to find the bridge closed.