During the late summer and early fall, high saline water upwelled along the west coast of Vancouver Island makes its way into the inland basins, including Saanich Inlet and the Strait of Georgia. However, the fortnightly tides mix and alter the deep water as it transits through the Straits and channels. Eventually this dense seawater flows into the basins. Tied to the tides, it flows in during very specific times, following the weak neap tides each month, flowing over the sill at Boundary Pass during flood tide. In this image we see the arrival of the dense, salty, warm water at the beginning of August 31, 2009. The gravity current associated with this dense flow also increases the near-bottom turbidity.