Terrestrial Environment
Terrain
The Greater Victoria Water Supply Area is largely comprised of the Nanaimo Lowland Physiographic Region. A physiographic region is an area having similar climate, geology and broad-scale plant communities. The Nanaimo Lowland Physiographic Region occurs below 600 m elevation on the east coast of Vancouver Island from Victoria to Campbell River and includes the Gulf Islands. Within the Water Supply Area the terrain is gently rolling and relatively uniform. The northeast portions of the Sooke and Goldstream Watersheds consist of well rounded and hummocky hills with minor bluffs and cliffs. This terrain takes on a plateau-like character in the Butchart/Lubbe Reservoir area. Both water supply areas contain a limited amount of steeper terrain.
Vegetation
Coastal Douglas-fir is the dominant tree species. Due to the longevity of this tree and the history of repeated fire and windthrow disturbance in the area, rarely do any sites proceed to a forest dominated by other species. If CRD Water Services removed these disturbances, other tree species, such as western hemlock and western red cedar would out-compete the fir and eventually dominate. Other trees that occur are red cedar, pine, arbutus, grand fir, alder, and maple. Shrubs include salal, Oregon-grape, huckleberry, baldhip rose, ocean spray, false azalea, salmonberry, devil's club and Labrador tea. The technical name for this ecosystem is the Coastal Western Hemlock very dry maritime biogeoclimatic subzone (CWHxm). This subzone dominates the watersheds, although there is a small component of the moist maritime Coastal Douglas-Fir (CDFmm) subzone as well.