Water quality standards are set by B.C. Ministry of Health in the Drinking Water Protection Act (SBC 2001) and its Regulations. Oversight of water quality regulations for the District is administered by Vancouver Island Health Authority (aka Island Health).
For a full list of water quality recommendations, Health Canada publishes the Guidelines for Canadian Drinking Water Quality in collaboration with the provinces.
Advisory: Tri-halomethane
In 2003, the District instituted an ADVISORY to residents regarding the presence of Disinfectant By-products in the drinking water which have been identified as potentially cancer causing under long term exposure. These Tri-halomethane (“THM”) compounds are formed by a reaction between naturally occurring elements in the water, and the chlorine used for disinfection.
Testing has indicated that THM levels exceed the Maximum Acceptable Concentration (“MAC”) in the Guidelines for Canadian Drinking Water Quality (“CDWQ”). Changes in water treatment completed during Project Blend are expected to deal with this concern.
Residents concerned about the level of THM should use an alternate source of drinking water, use an activated carbon filter certified to the NSF Standard 53, or boil drinking water for a minimum of 1 minute.
Permanent Advisory: Sodium Levels
Sodium is a natural element in well water and sodium chloride is used in the tannin removal process at Well #4. The sodium and potassium levels of water in the system are below the MAC in the CDWQ Guideline, but exceed the alert level for people on sodium restricted diets (20 mg/L). Such people should use an alternate source of drinking water.
Information: Lead in Drinking Water
The presence of lead in drinking water is an area of concern, both naturally occurring amounts and lead contained in the brass components of water pipe infrastructure (lead was added to brass to improve ductility and machinability). Recent work by authorities across North America have developed material standards to reduce the presence of lead contained in alloys used to produce system components. In particular the the use of materials designated as no-lead brass and conforming to the NSF/ANSI 61 standard is now the law in Canada (usually denoted with a NL stamped on the fitting).
But many old brass fittings contain lead in excess of the new standard. And the leaching of lead from brass fittings can be accelerated in waters with lower pH.
Scott Point Waterworks District has many old fittings. And as the product water has pH levels of 7.0 or lower, these fittings could pose a higher risk.
The District monitors for the presence of lead in its annual Metals Scan. At times, the amount of lead has shown to increase during the treatment process indicating the leaching of lead from old fittings. But it is important to note that: NO SAMPLE HAS INDICATED LEAD CONCENTRATION IN PRODUCT WATER EXCEEDING the MAC level of 10 parts per billion (10 micrograms/L) contained in the CDWQ Guideline.
ACTION: To reduce the risk posed from older brass fittings, the District has a replacement plan:
- Project Blend will result in the replacement of all older brass fittings at water treatment plants with PVC fittings, stainless steel fittings, or brass fittings specified as meeting the NSF 61 standard.
- Older meters, and back flow valves will be replaced at about 3-4 per year, starting with the oldest, most used meter sets.
- The sampling program will continue its focus on the presence of lead in the product water.
Information: Asbestos in Drinking Water
Like many municipal systems installed in the mid 20th century, the District’s 4-inch diameter Main is constructed of Concrete Asbestos pipe. About 15% fibres were added to the concrete mix to improve the strength of the pipe.
Given the focus on removing asbestos from the environment as a result of its toxicity effects on lungs, people have naturally been concerned about its use in water piping.
Based on a body of evidence on the effects of ingestion of asbestos through drinking water, the World Health Organization has concluded that:
Although asbestos is a known human carcinogen by the inhalation route, available epidemiological studies do not support the hypothesis that an increased cancer risk is associated with the ingestion of asbestos in drinking-water. Moreover, in extensive feeding studies in animals, asbestos has not consistently increased the incidence of tumours of the gastrointestinal tract. There is therefore no consistent, convincing evidence that ingested asbestos is hazardous to health, and it is concluded that there is no need to establish a guideline for asbestos in drinking-water.
This finding is confirmed in the CDWQ Guideline which states that:
Asbestos – Guideline value not necessary; no evidence of adverse health effects to exposure through drinking water.
Water Quality Testing Plan
A water sampling and testing plan is approved annually by the Vancouver Island Health Authority. WATER QUALITY TESTING PLAN.
BC Drinking Water Protection Regulations
Water Quality Standards for Potable Water
(sections 2 and 9)
| Parameter: | Standard: | |
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| Fecal coliform bacteria | No detectable fecal coliform bacteria per 100 ml | |
| Escherichia coli | No detectable Escherichia coli per 100 ml | |
| Total coliform bacteria | ||
| (a) 1 sample in a 30 day period | No detectable total coliform bacteria per 100 ml | |
| (b) more than 1 sample in a 30 day period | At least 90% of samples have no detectable total coliformbacteria per 100 ml and no sample has more than 10 totalcoliform bacteria per 100 ml | |
Frequency of Monitoring Samples for
Prescribed Water Supply Systems
(section 8)
| Population Served by the PrescribedWater Supply System: | Number of Samples Per Month: | |
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| less than 5 000 | 4 | |
| 5 000 to 90 000 | 1 per 1 000 of population | |
| more than 90 000 | 90 plus 1 per 10 000 of population in excess of 90 000 | |