This project built on a 2011 study that recommended finding out what threats existing stormwater outfalls posed to drinking water quality in the North Kalamalka Lake intake protection zone (IPZ).
Greater Vernon Water (GVW), in cooperation with the District of Coldstream (DoC), began the project by locating and marking by GPS the existing stormwater outfalls in the IPZ and then determining which sites would be most suitable for testing. Site visits were done during rainfall events or periods of high snow melt and samples were taken at sites where sufficient flow occurred.
Of the nine accessible outfalls that discharged directly into Kalamalka Lake, five were able to be sampled for contaminants such as TSS, fecal coliforms, E. coli, chloride, nitrate-N, and dissolved phosphorus. Results indicated the need for remedial action for several outfalls due to the risk they posed in the IPZ.
The findings of the study allowed GVW and DoC to develop a priority and feasibility plan for improving the outfall discharge. Other organizations looking to follow a similar course of action may use this project as a baseline.