Cranbrook's Water Supply

Water was a top priority for Cranbrook Connected.  It costs a lot a money to treat and distribute potable water to the taps in our homes.  Compared to other parts of the world we are fortunate to have the water supply we do but more needs to be done in parts of Canada and in Cranbrook to bring it up to modern standards. 

This excerpt is from The City's Growth Management Study.

3.4 CONCLUSIONS AND RECOMMENDATIONS

The City of Cranbrook’s water treatment does not fully comply with the Interior Health Authority (IHA)’s 4-3-2-1-0 drinking water objective performance targets. The following provides a summary of how the City’s treatment performance measured with the various objectives:

4. The City of Cranbrook’s use of chlorine for disinfection is generally effective in inactivating viruses and bacteria as CT values are adequate most of the time. There were only approximately 10 days in 2007 and 2008 that the CT requirement was not met.

3. Chlorine has limited effectiveness against Giardia and is ineffective against Cryptosporidium. Both Giardia and Cryptosporidium parasites with potential for severe implications for the elderly, the young or those residents with weaker or compromised immune systems. Given the City’s current method of treatment, these parasites cannot be effectively removed from the surface water supply. This is likely evidenced by the gastrointestinal disease outbreak which was experienced by the City in 1996.


2. To meet the dual treatment processes rule for surface water or unprotected groundwater, the City would be required to provide a secondary method of treatment such as filtration or additional disinfection through ultraviolet light (UV)


1. 95% of the time the City’s settled water turbidity is less or equal to 1.3 NTU. In order to meet the 1 NTU guideline, additional filtration treatment of surface water is required.


0. Although no evidence of E.Coli was measured in 2007-2008, there were several positive indications of fecal coliforms. In order to eliminate the occurrence of E.Coli and Fecal Coliforms in the City’s potable water, additional treatment is required via filtration or UV disinfection.

It is recommended that an additional treatment process (e.g. filtration or UV disinfection or both)be implemented at the existing Phillips Reservoir Treatment Facility to reduce the risk of illness due to Giardia, Cryptosporidium and other pathogens and bacteria present in the source waters. The existing monitoring of raw water samples for these protozoa along with other water quality parameters should be maintained.