This summer's low water is gone... now that the big storm, Sandy, has hit the area with lots of rain. With the rising water, the lowest stream terraces will be submerged, and so will the ubiquitous pattern of the imbricated stream rocks that line the stream banks.
In this photo the current is from the left.
This photo of a waterfall shows a definite pattern in the rocks surrounding the plunge pool.
Here the rocks are mostly submerged, but with the knowledge of this stream process, you can see that the rocks are inclined basinward.
Here is a photo of a stream bed with a little water trickling among the imbricated rocks. It would take a much higher flow to mobilize the bed load in this streambed.
I suspect Hurricane Sandy will rearrange the bed load of our streams and rivers around here. She'll probably "re-imbricate" some rocks that have been moved around by people and things other than stream processes.