Not surprised. The bottom of Norristown near the river is very low ground and prone to flooding. We're on a creek that drains into Wissahickon Creek, which in turns dumps into the Schuylkill River. The Schuylkill is quick to flood, as it is shallow and drains many local creeks. There are creeks all over this area, and back in colonial times it was known for its many mills, which were powered by those very creeks. Fortunately we also tend to drain quickly once the rains stop. The same can't be said for the Delaware River. With all the rain north of us, flooding on the Delaware could be pretty serious over several days.
Yeah, the Delaware is going to get hammered. A few weeks after Ivan, in 2004, we were canoeing the Delaware River near Bushkill. Ten or more feet up in trees there was debris stuck in branches which was left from the high water mark. Most of the island campsites were washed out and have not been reopened since then.
Partly as a result of that storm, a stretch of Rt. 206 which parallels the river near Bushkill (and frequently gets flooded) is going to be cut off from through traffic. It’s use will be limited to those using the DE Water Gap Recreation Area. A higher ground thru route is being constructed.