At the very least, wait until the Harbormasters of Baltimore and Norfolk open the ports back up and allow large ships in. They only do that when they are sure they can get a ship from the open ocean all the way to a pier. Then you have reasonable assurance the worst of the crap is out of the channels and areas close by. I wouldn't go gunkholing for a month. Stuff can take that long to wash down from the streams.
It might take a few weeks at least for storm- and flood-related debris to get washed down Bay. Keep in mind, also, that at some point Conowingo Dam in the Susquehanna River might have to do a release to get rid of crap.