Kapoor tunnel
Encyclopedia
The Kapoor Tunnel is a straight 8.8 km (5.5 mi) subterranean route which is currently the main transport of water from the Sooke Lake to the Westshore
, City of Victoria
, Esquimalt
, and the Saanich Peninsula
. When it was determined that the Sooke Flowline
would no longer meet the region's needs, the decision was made to excavate the tunnel. Prior to construction of the flowline, Arthur Adams, the consultant for the flowline construction, had proposed the Kapoor Tunnel be built. Unfortunately, that era's technology was not yet up to the task.
(TBM), which was built in Vancouver at a cost of $258,000. Excavation was undertaken from both ends with the intention of meeting in the middle. The machine was later abandoned and excavation was carried out manually due to the soft rock clogging the teeth and gears and causing motor burn outs. The contractor quit and the water district completed the task in 1967. On completion, the tunnel was an engineering success. Even without modern laser technology, the tunnel was joined only 6 in (15.2 cm) off line.The project was almost incident free with the only major injury occurring when a worker lost an eye drilling into a hole containing an undetonated stick of dynamite.
The project was a challenging feat due to a variety of factors:
Plant near Goldstream Provincial Park
.
Every January, the tunnel is shut off and the city transfers over to the district's secondary Goldstream system. Workers must walk the 8.8 km (5.5 mi) route to look for cracks and other defects.
Langford, British Columbia
Langford is a city of 22,459 residents on southern Vancouver Island, within the province of British Columbia, Canada. It is considered one of Greater Victoria's Western Communities...
, City of Victoria
Victoria, British Columbia
Victoria is the capital city of British Columbia, Canada and is located on the southern tip of Vancouver Island off Canada's Pacific coast. The city has a population of about 78,000 within the metropolitan area of Greater Victoria, which has a population of 360,063, the 15th most populous Canadian...
, Esquimalt
Esquimalt, British Columbia
The Township of Esquimalt is a municipality at the southern tip of Vancouver Island, in British Columbia, Canada. It is bordered to the east by the provincial capital, Victoria, to the south by the Strait of Juan de Fuca, to the west by Esquimalt Harbour and Royal Roads, to the northwest by the...
, and the Saanich Peninsula
Saanich Peninsula
The Saanich Peninsula is located north of Victoria, British Columbia, Canada. It is bounded by the Saanich Inlet on the west, and various straits of the Gulf of Georgia on the east, chiefly Haro Strait The exact southern boundary of what is referred to as the "Saanich Peninsula" is somewhat fluid...
. When it was determined that the Sooke Flowline
Sooke Flowline
The Sooke Flowline is an abandoned 44 kilometer concrete aqueduct that snakes through the Sooke Hills from Sooke Lake to the Humpback Reservoir near Mt. Wells Regional Park. From this reservoir, a buried, riveted steel pressure main transported water to Victoria. In between 1994 and 2007, this...
would no longer meet the region's needs, the decision was made to excavate the tunnel. Prior to construction of the flowline, Arthur Adams, the consultant for the flowline construction, had proposed the Kapoor Tunnel be built. Unfortunately, that era's technology was not yet up to the task.
Construction
The tunnel was formed by a miniature tunnel boring machineTunnel boring machine
A tunnel boring machine also known as a "mole", is a machine used to excavate tunnels with a circular cross section through a variety of soil and rock strata. They can bore through anything from hard rock to sand. Tunnel diameters can range from a metre to almost 16 metres to date...
(TBM), which was built in Vancouver at a cost of $258,000. Excavation was undertaken from both ends with the intention of meeting in the middle. The machine was later abandoned and excavation was carried out manually due to the soft rock clogging the teeth and gears and causing motor burn outs. The contractor quit and the water district completed the task in 1967. On completion, the tunnel was an engineering success. Even without modern laser technology, the tunnel was joined only 6 in (15.2 cm) off line.The project was almost incident free with the only major injury occurring when a worker lost an eye drilling into a hole containing an undetonated stick of dynamite.
The project was a challenging feat due to a variety of factors:
- The rock the tunnel was being bored through was a crumbly, unstable shale
- Close quarters meant that only one cart could travel in the tunnel at a time
- The tight space meant that only three men could work at the rock face, limiting progress to 7 m (23 ft) metres per day
- Fresh air needed to be pumped in from the surface deep into the tunnel
- The narrow gauge railway restricted how much cement could be sent into the tunnel and slowed the lining process to 24 m (78.7 ft) per day.
Route
The tunnel runs from the head tank near Sooke Lake, which maintains a constant pressure to the Japan Gulch UVUltraviolet germicidal irradiation
Ultraviolet germicidal irradiation is a sterilization method that uses ultraviolet light at sufficiently short wavelength to kill microorganisms. It is used in a variety of applications, such as food, air and water purification. UV has been a known mutagen at the cellular level for more than...
Plant near Goldstream Provincial Park
Goldstream Provincial Park
Goldstream Provincial Park is a provincial park in British Columbia, Canada. It is known for the annual fall salmon runs in the Goldstream River, and the large numbers of bald eagles that congregate to feed at that time. The total size of the park is 3.79 square kilometres. It is located in the...
.
Maintenance
This tunnel can convey 580 million litres/day, 10 times greater than the Sooke Flowline, and provides water to all municipalities, except Sooke and the Highlands. At a final cost of $5.6 million, it was money well spent since the Sooke Flowline was leaking and was vulnerable to blow downs and rock slides.Every January, the tunnel is shut off and the city transfers over to the district's secondary Goldstream system. Workers must walk the 8.8 km (5.5 mi) route to look for cracks and other defects.