News » Environment

Whistler's watersheds

"Treat these waterways with care"



Whistler Naturalists

Imagine the typical branching pattern of a tree, or the evidence of Jack’s frosty fingertip on your winter window, and you can approximate the arrangement of waterways in the Whistler valley.

Then alter this pattern to describe the incline of these mountains, and add another dimension or two to account for groundwater and montane aquifers, and you’ll begin to sense that we live amid a vast and elaborate system of watersheds, which support an abundance of biological characters.

This is hardly news. It would be difficult to go a day in this valley without having some contact with its wealth of water. Plate tectonics initiated what the most recent glacial presence then shaped, around 10,000 years ago, into a region decorated with lakes, rivers, wetlands and streams; and which, for thousands of years, remained isolated, used only by the Coast Salish First Nations people as a hunting and fishing heaven.

Everyone on earth lives within a watershed. Determined by the topography of a region rather than political boundaries, watersheds are areas of land defined by the particular flow of rainwater or melting snow and ice.

Whistler’s watersheds are delineated by the uppermost ridges of our surrounding mountain ranges, which move rainfall and glacial meltwater into the valley by countless creeks and streams. There are also a few aquifers in our midst, water that is stored in permeable rock under varying degrees of pressure and which comes to the surface as springs.

In the Whistler valley, there are two major watersheds. There is a high point in the valley floor, located in the vicinity of Alta Lake that once diverted water from the lake both north and south. However, land and rail developments at the southern end cut off drainage to Nita Lake and outflow was entirely redirected to the north end, through the River of Golden Dreams to Green Lake. This water continues north to Pemberton, gamboling down the Green River, picking up power from the Soo River and Rutherford Creek on its way to crashing down a fracture in the granite wall of Mount Currie, dropping 197 feet as Nairn Falls. The journey continues to Lillooet Lake, where the water begins its bow back to the Lower Mainland, draining through Harrison Lake to the Fraser River and then on to the Pacific Ocean.

The water that moves southward out of the valley drains through Nita and Alpha Lakes, and then on into Millar Creek, which fuels a wetland before fetching up with the Cheakamus River. The mighty Cheakamus combines with Callaghan Creek before descending Brandywine falls, then languishes a bit in the Daisy Lake reservoir before being released into the Squamish River and eventually out to Howe Sound.

This is a simplified overview. There are a legion of flows adding into the energy of the whole system, at countless junctures; the tree, branching, but with the flow of energy reversed.

This complexity underlies the fact that the watershed is where much of the hydrologic cycle occurs. No new water is ever made – it is continuously recycled as it moves through the watershed – and the quality of the water resource is largely dependent upon the capacity of the watershed to buffer impacts and absorb pollution.

It is necessary for us to treat these waterways with care, both for their own sake and for the sake of our neighbours downstream. Besides providing the world’s fresh water, watersheds support a diverse array of habitats that form the integrity of the wildlife support system. Whistler’s watersheds have given rise to a riparian area that runs the entire length of the valley, and which supports over half of our resident wildlife.

Everything that we do, from land use practices to wastewater management, has an effect on the system. There are infinite connections that we do not see, and everything is taken up by the flow of water; eventually, even, those towering mountains.