Research and Development
Ultraviolet Light Disinfection Program
With the addition of UV reactors, the City's Water Utility will be providing its customers with a multi-barrier disinfection system consisting of UV primary disinfection followed by chlorination as a secondary treatment method.
The City’s water utility supplies water to more than 50,000 residents and more than 1,700 industrial, commercial and institutional properties in north, central and south Kelowna. The raw water source is Okanagan Lake, with four intake locations.
Previously water treatment has been limited to chlorine disinfection. However in recent years concerns over water quality and protozoa such as Giardia and Cryptosporidia have led the City to seek enhancements to the primary disinfection system at all intake locations.
After much research and completion of a thorough testing program, ultraviolet light treatment was found to be effective in inactivating Giardia and Cryptosporidia. UV exposure does not kill these parasites present in the source water, however it renders the parasites unable to reproduce and as a result their ability to cause illness is eliminated.
UV transmitters are being installed at all four lake intakes; water flowing through the transmitters is exposed to the UV light provided by four 1,000 watt lamps for only fractions of a second. Lamp intensity automatically adjusts to respond to variances in water quality and velocity.
The construction phase for the Ultraviolet light disinfection equipment is nearing completion. Construction work began in January 2005 with the installation of the UV reactors at three of the four Okanagan Lake intake locations; Poplar Point, Eldorado Road and Swick Road.
Funding
City staff worked in close cooperation with various levels of government, including the Ministry of Health and the Ministry of Community, Aboriginal and Women’s services, on this project. The City of Kelowna was able to secure a grant of $2.95 million, under the Canada/British Columbia Infrastructure Program, to help off–set the total construction costs of $7.3 million for the Poplar Point, Eldorado and Swick stations.
Poplar Point
Work at the Poplar Point site included a new intake pipe, installation of two 1200mm UV reactors and modifications to the existing pump station equipment. Phase 1 of this project will undergo testing and commissioning this fall and the new facility is expected to be fully operational in November.
Eldorado Road
Construction work at the Eldorado Road intake location is complete and the project is now in the commissioning stage. This project involved the construction of a new building above the existing intake pipe and installation of a 1200mm UV reactor. Testing and commissioning of this new facility will be complete in October and ready to be placed on-line this fall.
Swick Road
The Swick Road reactor is considerably smaller at 450mm diameter. Commissioning of the Swick Road UV disinfection facility is currently underway and the unit will be placed on-line in October 2005.
Cedar Creek
Detailed design for the Cedar Creek facility will begin this fall and is expected to be complete in spring 2006. Construction of the new pump station and UV facility is expected to begin in the 2006 construction season and carry over into 2007.
