After trying, and failing, to move to the Schuylkill River, the Duck Boats will return to Delaware River in a couple of days. They are shortening their time in the water, putting a permanent lookout on the pier where they enter, and must have a high speed rescue/tow boat available. All of this is because they will still enter the water right into a busy shipping channel (no way to avoid that on the Philly side of the river), which is a very sub-optimal situation:
I'll have to wait to see what their full route is, but this article
says they will stay within 100 feet of shore - which means they'll be right in the shipping channel the whole time. It seems to me it would be much safer to just proceed across the channel as quickly as possible (upon clearance from their lookout), and head down the river outside the channel.