Cowichan Stat ion Aquifer (198)
Cowichan Station is a 6.1 km
2
predominant shale bedrock aquifer with some sandstone
layers, south of the Cowichan River estuary, and east of the Koksilah River floodplain. The
eastern boundary of this aquifer occurs below the Cherry Point aquifer. Cowichan Station
aquifer is described as having low productivity with a reported yield range of 0.06-1.26 L/s.
This aquifer is described as having low vulnerability, and the direction of flow has not been
determined. Water use is domestic while water reliance is conjunctive. Water licenses exist
on Treffery Creek, Koksilah River, Webb Brook and Giese Brook. Many wells in the area are
completed in the overlaying Cherry Point aquifer.
Kelvin Creek Aquifer (200)
This is a 27.7 km
2
bedrock upland aquifer comprised of crystalline and volcanic rock, south of
the Cowichan River valley between Koksilah River and Kelvin Creek. The western boundary
is hypothesized to extent to the Koksilah Ridge. Overlaying sediments are predominantly
ground moraine. This aquifer has low productivity with a yield of from 0.02 to 1.58 L/s. The
aquifer has moderate vulnerability with about one third of reported wells having indicating no
confining cover. The direction of flow and recharge mechanisms have not been determined.
Water use is domestic and water reliance is conjunctive. Several water licenses exist on
Koksilah River and Kelvin Creek. Water licenses also exist on springs and unnamed streams
in the area.
Nor th Shawnigan Aquifer (202)
The 20 km
2
North Shawnigan aquifer is comprised predominantly by volcanics and divided by
the San Juan Fault with bedrock being older to the north of the fault. The aquifer is located
north of the Shawnigan lake watershed basin, and bounded to west by the Koksilah River,
east by Shawnigan Creek and to the north and east by Cobble Hill. This aquifer is determined
as having low productivity with a range of yields from 0.02 to 5.68 L/s. The direction of flow
and recharge mechanisms have not been determined. Groundwater wells in this aquifer are
used for municipal and commercial purposes, water reliance is conjunctive. Numerous water
licenses exist on Shawnigan Lake and other creeks, streams and springs in the area. The
Kingburne aquifer occurs above the northern central part of the North Shawnigan Aquifer.
Shawnigan Lake Aquifer (203)
This 30.5 km
2
predominant gneiss aquifer is located in the Shawnigan Lake watershed basin.
The productivity is reported as low with a range in yield from 0.01 to 4.42 L/s. The
vulnerability of this aquifer is high with about half of the reported wells indicating no protective
overburden cover. Direction of flow has not been determined however it is probable that the
direction of flow is toward Shawnigan Lake. Recharge has not been determined but it has
been hypothesized that precipitation and runoff from surrounding mountains provide recharge
for this aquifer. Groundwater wells in this aquifer are used for irrigation and for community
water supply. Water reliance is conjunctive with several licenses on Shawnigan Lake, creeks,
streams and springs in the area.
Cobble Hi l l Aquifer (204)
The Cobble Hill aquifer is a 21.4 km
2
predominant granodiorite and quartz aquifer in the Mill
Bay and Cobble Hill area. Its southern boundary is Shawnigan Creek, the western boundary
is the base of Cobble Hill and the eastern boundary is Saanich Inlet, while the northern
