Goldstream Water Supply Area (WSA) is located northwest of the City of Victoria in the Sooke Hills, adjacent to the Sooke Water Supply Area. The Goldstream WSA is 2,307 ha in size and contains four surface water reservoirs that are used as a secondary water supply source for the Greater Victoria Water Supply System.
Water moves from Butchart to Lubbe to Goldstream reservoirs via surface stream channels and is then released into the Goldstream River which flows into Japan Gulch Reservoir where a water intake tower is located just upstream of the Japan Gulch Water Disinfection Facility. The storage capacity of the Goldstream system is approximately 10 million cubic metres, which is about 1/10 of the capacity of Sooke system.
There are 10 dams on the four source water reservoirs in the Goldstream Water Supply Area. These dams were built between 1892 and 1914. The main dams were upgraded to meet modern seismic standards in the mid-1990s.
Water from the Goldstream supply is typically only used during the one-week annual maintenance of water supply infrastructure of the primary Sooke supply system. However, water from the Goldstream system can be used in the event of a short term water quality issue or emergency in Sooke Lake Reservoir. The useable storage volume of these reservoirs holds the equivalent of 31 days of average summer daily demand or 52 days of average winter daily demand.
At the request of the Federal Department of Fisheries and Oceans, water is released from the Goldstream reservoirs in the summer and fall to maintain minimum flows in the Goldstream River. This water release sustains the salmon population in the river and meets the water requirements of the Howard English Fish Hatchery. Typically about 4.5 million cubic metres (45% of the available water supply of the Goldstream reservoirs) is released each year.