The BC Ministry of Health determines specific monitoring requirements for all water utilities on an individual basis. At mimimum, water systems are monitored once per month for the presence of bacteria.
In the BC Drinking Water Protection Act, the BC Ministry of Health has identified five objectives (referred to as 4-3-2-1-0) for providing water that is safe for consumption. These objectives are implemented locally by Interior Health.The BC Ministry of Health's 4-3-2-1-0 Drinking Water Objective [PDF - 33 KB] represent a combination of the following:
- 4 log (99.99%) reduction in viruses
- 3 log (99.9%) reduction in pathogens
- 2 methods of treatment
- 1 nephelometric turbidity unit (NTU) (a measure of cloudiness)
- 0 coliforms
The ultimate goal is to protect human health. The RDCK works with Interior Health to incorporate the 4-3-2-1-0 objectives into our operations. Most microorganisms are easily removed from water through disinfection and filtration. By combining methods, a stronger barrier is created for preventing their presence in drinking water. As a result, the risk to human health is reduced.
Interior Health facilitates the sampling, transporting, and laboratory analysis for small water systems. Bacteriological and chemical sample results are stored in the Interior Health database on their website.
Coliforms (both total and fecal) are commonly found in the natural environment and are frequently used as indicator organisms. If coliforms are present in drinking water, it suggests that contamination may have occurred. The BC Drinking Water Protection Act requires that drinking water be sampled regularly for the presence of coliforms as well as Escherichia coli (E.coli). Specific strains of E.coli and fecal coliforms have led to severe illness or even death. These bacteria must be eliminated from drinking water to minimize risk to human health.
Bacteriological analysis is performed routinely to test for total coliforms and E.coli. Water is generally considered safe when a sample contains:
- 0 detectable fecal coliform bacteria per 100 ml; and,
- 0 detectable E. coli per 100 ml.
If these levels are exceeded, the RDCK and Interior Health will take immediate corrective actions.
Excessive turbidity, or cloudiness, in drinking water is aesthetically unappealing, and may also represent a health concern. Evidence exists that controlling turbidity is a competent safeguard against pathogens in drinking water.
Health risks increase as turbidity rises, particularly for at-risk populations such as newborns, the elderly, and people with weakened immune systems. Contaminants such as viruses, bacteria, and parasites can attach themselves to the suspended particles in turbid water. These particles can then interfere with disinfection, limiting chlorine's ability to remove or inactivate the contaminants. Turbidity levels as recommended in the Guidelines for Canadian Drinking Water Quality are as follows:
- 1-5 NTU - Fair
- +5 NTU - Poor
Interior Health has developed a Frequently Asked Questions sheet on Turbidity in Drinking Water [PDF - 258 KB]
Boil Water Notices
The Regional District has a responsibility to issue a Boil Water Notice when there is an unacceptable level of bacteria or organic material in the water supply. To rescind a Boil Water Notice, approval from Interior Health is required.
What does a Boil Water Notice mean?
When a Boil Water Notice is issued Interior Health informs residents to bring any water intended for human consumption to a rolling boil for a minimum of 1 full minute. Boiling water should kill the bacteria and pathogens that may be present in any given water source. Boiling will not remove any heavy metals, as these contaminants can only be filtered out.
The RDCK and Interior Health recommend that all customers drink boiled water or a safe alternative until the Boil Water Notice is rescinded. Water intended for drinking, washing fruits and vegetables, making beverages or ice, or brushing teeth should be boiled for one minute. Boiled water should then be refrigerated in a clean, covered container. Customers could also choose to use bottled or distilled water, or water that has been filtered through a well-maintained treatment device.
To find out if your drinking water system is under a Boil Water Notice if you are not serviced by an RDCK water system, please check Interior Health's database.
The RDCK also maintains a list of Current Notifications and Advisories by water system.
For public protection and enjoyment, water is tested by the RDCK at Taghum Beach Regional Park for the presence of Fecal Coliforms during the summer season (June-September).
The maximum allowable number of E. coli bacteria in recreational water is 200 per 100-millilitre sample. When this limit is exceeded a Swim Advisory (Water Quality Notice) will be issued by the RDCK. This notifies the public that bacterial levels are higher than those allowed in the Guidelines for Canadian Recreational Water Quality.
A swimmer's risk of infection is directly related to bacterial counts in the water. When average E. coli counts reach 200 units per 100 millilitre sample, it's expected that one per cent of bathers may develop gastrointestinal illness (GI) if these bacteria are ingested. For every one GI illness, two to three other illnesses - skin rashes (swimmer's itch excluded) and eye, ear and throat symptoms - can be expected. The very young, the elderly and people with weakened immunity are the most susceptible to these illnesses.
Once testing shows bacteria levels have returned to acceptable levels the Swim Advisory will be lifted and the signage removed.
- Avoid swallowing lake water
- Avoid swimming with an open cut or wound
- Avoid swimming for 24-hours after a significant rainfall
- Wash your hands before handling food
Protect the Beach
- Don't feed the birds
- Keep your pet on a leash
- Don't litter or discard food on the beach
- Change diapered children in the bathroom frequently, not at the beach
- Dispose of boat sewage in onshore sanitary facilities
- Stay away from the water if you are experiencing digestive or intestinal problems
- Wash your hands with soap and water after using the toilet or after changing diapers
- Call 1-800 268-7325 if you see something that needs our attention
- Never bury waste in beach sand
Understanding Beach Water Quality
Disease-causing microorganisms in water include bacteria, viruses and parasites (e.g. Giardia and Cryptosporidium). These organisms can be discharged directly to water bodies or transported with surface runoff. Sources are numerous and include discharge of untreated sewage, runoff from agricultural activities and waste from waterfowl and other animals (wild or domestic). Fertilizers, pesticides, and garbage can also contaminate beach water.
Beach water quality is typically poorer in the summer due to warmer water temperatures and higher numbers of people on or around the beach. Contamination is also more likely to increase during and after rainstorms.
Escherichia coli ( E. coli ) belongs to a group of bacteria called fecal coliforms that originate in the digestive tract of warm-blooded animals.
Why are there sometimes contaminants in my drinking water?
Many water systems in BC draw their drinking water straight from surface sources. Many microbiological contaminants occur naturally and are part of a functioning ecosystem. Other contaminants are the result of metals leaching from the ground or from the introduction of fecal matter from livestock or wildlife.
Who is most at risk from drinking water contamination?
Everyone is at risk from water contamination. However, the very young, the very old, and people with suppressed immune systems are most at risk of becoming ill.
What are the benefits and drawbacks of using chlorine to treat my drinking water?
When using chlorine as the sole treatment method, high doses of chlorine are required for extended periods of contact time. The amount of chlorine required and the time required depends on the temperature and chemistry of the water. If organics are present in the source water and chlorine is used as a treatment method, the chlorine can react with the organics and produce byproducts that create odour and taste problems.
Modern drinking water treatment processes, like those used at many Regional District facilities, use filtration to remove the organics and microorganisms followed by ultraviolet light to kill any harmful microorganisms that may have passed through the filtration process. Once all the organics have been removed from the water, a very small amount of chlorine is added to maintain the quality of the water as it travels through pipes to your tap. Chlorine in this concentration does not produce odour problems, taste problems or, without any organics for the chlorine to react with, harmful byproducts.
For more information on the benefits and drawbacks of chlorine, please see Health Canada's website on drinking water chlorination.
How can I remove chlorine from my drinking water?
Chlorine can be easily removed from drinking water using a simple carbon filter (e.g. Brita filters) or by letting water stand overnight in a clean, covered jug.
Can I acquire immunity to the microorganisms in drinking water?
Immunity is not possible. However, the symptoms of gastrointestinal illness (e.g. stomach cramps, bloating, gas, diarrhea, etc.) may be reduced with long-term exposure. This desensitization does not fully protect the individual from large and sudden doses of contaminants.
Why is my water system on a Boil Water Notice?
The Regional District has the responsibility to issue a Boil Water Notice when sample results indicate the presence of certain microorganisms (i.e., coliforms) or pathogens (i.e., E. coli) or when turbidity levels are above established parameters.
When can I expect the Boil Water Notice on my water system to be lifted?
Only Interior Health can lift a Boil Water Notice. In general, Interior Health requires a water system to have two weeks of consistent sample results indicating zero coliforms and turbidity levels below established parameters.
The content on this page was last updated June 14 2018 at 12:46 PM