In the event that the subdivision is traversed by any watercourse, channel, stream or creek, the subdivider may be required to dedicate rights-of-way or easements for storm drainage purposes, conforming substantially with the lines of such watercourse, channel, stream, or creek, or to provide by dedication further and sufficient rights-of-way or easements as shall be required for structures or channel changes or both, to dispose of such surface and storm waters. (Ord. 5793-NS § 2 (part), 1987)