Stream Class Definitions from The Forestry Practices Code 2000 :
Rivers, lakes, artificial storages (other than farm dams) and tidal waters – generally those named on 1:100 000 topographical series maps.
Creeks, streams and other watercourses from the point where their catchment exceeds 100 ha (1 km2).
Watercourses carrying running water most of the year between the points where their catchment is from 50 to 100 ha (0.5–1 km2).
All other watercourses carrying water for part or all of the year for most years.
A Class 4 watercourse is differentiated from a drainage depression by having at least one of the following features:
- A gravelly, pebbly, rocky or sandy bed, indicative of flowing water;
- An obvious gully;
- A short steep section of streambank adjacent to the watercourse bed.