Bedrock Channel Streams

Here is a question I have been thinking about. In a bedrock channel stream, although the streambanks are not alluvial in nature, nonetheless, there is often a defined bank, either by vegetation or a morphometric or geometric break. Is there a characteristic discharge associated with these banks or is it just marking the last big flood to flow through and scour off the vegetation? I am not sure.



Five Mile Creek near Nelson is a creek I did not survey because it had an almost totally bedrock reach above the gauge.

In work news, I'm testing out ArcGIS 9.2 and seeing how it syncs with HEC-GEORAS