The Kapoor Tunnel is a straight 8.8 km (5.5 mi) subterranean route which is 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.

The project was almost incident free with the only major injury occurring when a worker's eye was damaged while drilling into a hole containing an undetonated stick of dynamite.

The project was a challenging feat due to a variety of factors: The tunnel runs from the head tank near Sooke Lake, which maintains a constant pressure to the Japan Gulch UV Plant near Goldstream Provincial Park.

Every January, the tunnel is shut off and the city transfers over to the district's secondary Goldstream system.