Restoring a Culturally Eutrophic Shallow Lake: Case Study on Quamichan Lake in North Cowichan, British Columbia

Quamichan Lake is a culturally eutrophic shallow lake located in North Cowichan on Vancouver Island in British Columbia. My research project examined the current trophic status and water quality of Quamichan Lake and investigated a number of watershed and in-lake restoration methods to return the lake back to mesotrophic (nutrient rich) conditions. Based on the data collected, Quamichan Lake is currently in a hypertrophic state caused by excess phosphorus inputs that leads to Cyanophyte phytoplankton species (cyanobacteria) to dominate during the summer. Eutrophication is both an environmental and human health issue as cyanobacteria algal blooms can disrupt the lake ecology and are toxic to most mammals. The goal of my research was to provide the Municipality of North Cowichan and Vancouver Island Health Authority with a comprehensive restoration plan to contribute to the restoration of Quamichan Lake and other lakes in southern Vancouver Island that are experiencing cultural eutrophication.