The polygons delineate the boundaries of each of the major sub-watersheds within City of Calgary boundaries. These include Bow River Direct, Elbow River, Fish Creek, Nose Creek, Pine Creek and Shepard Wetland/Western Headworks Canal. The sub-watersheds delineate the major drainage areas within The City. Polygons should be layered over an orthophoto of Calgary, with the rivers, creeks and streams visible. This data is updated on an as needed basis by Watershed Strategy and has been simplified for viewing purposes.