The nice thing about living in a flood plain is its fertile, rock-free soil. Here on the flood plains of the Wallkill River, I can dig a 3-foot-deep post hole in about 5 minutes. The soil here also drains well, allowing me to plant even during heavy rains.
The combination of heavy rains and winds loosened the grip of tree roots onto the soil. Some trees blew over. Some are wobbly in the soil. It may be possible to right and stake the former, and just stake the latter, if the trees are not too big. After a year or more, new roots will grow to provide sufficient support without the stakes.
Think of all the detritus carried along by that floodwater. And then try to imagine some of the stuff you didn’t think of. The major problems I see are floating gasoline and diesel cans and the major problem I smell is of the stuff in those cans. What I don’t see or smell is whatever is running off farm fields and the overflow from sewage treatment plants, not to mention harmful chemicals and bacteria.