I went here two weeks ago (end of Sept. 2006) and the water was very low. The asphalt ramp (Scott's Cove) was completely out of the water. I drove by there on 10/7/06 and it was even lower despite a fair amount of rain recently.
I don't know if Triadelphia is open yet (that was closed Spring, Summer and early Fall. I would call before I went to Triadelphia to make sure you can launch. I would pass up Rocky Gorge altogether.
Don't bother anymore in 2006.
At WSSC field office on Brighton Rd (off of RT 650 North)