DUKW emerging onshore

I'd always wondered how long it took and how easy it was for a DUKW to emerge from the water and land on a beach.  Now I know.  Yesterday I happened to be in Pittsburgh for a Geology convention and, during the lunch break, stumbled upon a flotilla of DUKWs carrying schoolchildren on the Allegheny River past downtown.  As we walked along, the DUKWs turned into the bank and emerged right in front of us.  They were travelling at c.5 knots in the water and emerged at a brisk walking pace (4-5 mph).  The shots below span less than 30 seconds.  They emerged on a concrete ramp angled at c. 30 degrees, so shallow beaches should have been relatively straightforward, unless there were traction problems in mud or soft sand.

Thanks for looking!