General Notes
Our sampling sites are installed on supply and distribution mains. We have sampling ports tapped into them that generally employ irrigation fittings. However, I don’t think you should tap into a homeowner’s water service line, as there is significant risk of causing a leak and any water quality issues or water loss on the resident’s side of the water meter are the responsibility of the resident. I strongly doubt that you would get permission from any of the municipalities to install sampling ports on their side of the meter as the risk of cross connection and contamination is significant.
In general, drinking water sampling from the home could be done from a faucet. But recognize that there could be influences between the sample site/faucet and the water flowing in the mains, so a home sample isn’t necessarily representative of the water in the mains. The primary influences I can think of are: pipe material of the service line from the meter to the house; pipes in the house; any home treatment such as filtration or water softeners; stagnant water. Water in the mains is the most representative of the water being served to Greater Victoria.
My suggestions for collecting a representative sample from a home are: sample from the cold water as hot water tanks influence the water due to stagnation and metals/sediment accumulation; remove the aeration screen on the faucet; let the water run until its cold to remove stagnant water; use a lab provided and appropriate sampling container for the tests; follow good sampling technique to reduce the chance of contamination from the sampler or environment.
As for testing, pH is the only somewhat reliable home test that I know of. And pH strips are much less accurate and precise than a lab test. I’ll speak to the parameters in the table below individually, but in general I would absolutely recommend lab testing from a certified lab.
Lab Testing
There are two commercial labs in Victoria that can do the analysis: Maxxam Analytics and MB Labs.
Bacteria
Bacteria – must be done at a lab; the bacteria of interest must be cultured for to see if it’s present in a sample; I have no recommendations because I don’t know the scope of your project and my expertise is in treated drinking water which monitors for bacteria listed in the BC Drinking Water Act & Regulations and the Guidelines for Canadian Drinking Water Quality
Physical-Chemical
Physical-Chemical – generally considered conventional parameters such as pH, conductivity, alkalinity, turbidity; some of these parameters can be influenced by the household factors I mentioned above
Disinfection by-products
Disinfection by-products – compounds that can form from reactions between the natural organic material in the water and chlorine; generally develop with contact time so we test for those in the further reaches of the system; regulated under the BC Drinking Water Act & Regulations as they can be carcinogenic if ingested in concentrations over the guideline values
Metals
Metals – from a drinking water perspective, most metals don’t have human health guidelines but have Aesthetic Objectives (AO) because they cause colour or appearances that are not pleasant – think blue-green staining from copper; lead has a human health Maximum Acceptable Concentration (MAC); metals can be picked up from any pipes that are not plastic PVC so the water in mains is the most representative of what is coming the residents
Parasites
Parasites – may be present in the raw water; disinfection/treatment processes remove parasites so they will not be present in the treated water
Algal toxins
Algal toxins – may be present in the raw water only when there is a cyanobacteria bloom of cyanobacteria species that have the capability of producing toxins; not all toxin producers always produce toxins; blooms are defined by specific criteria based on number of algal cells and species composition; disinfection/treatment process remove cyanotoxin so they will not be present in the treated water
Reporting and Doc Libary
Lastly, I’ve attached here the tables from our 2016 annual report summarizing all the testing we do on the raw and treated water – the 2017 annual report is being written this spring. As you can see, we focus a lot of the contaminants testing on the raw water. The water quality is very similar between the raw and treated water because our treatment processes are fairly simple and conservative. You can also see that the water quality is very stable and there is very little fluctuation seasonally or from year to year.
Taxonomy – Victoria CRD & Oak Bay
I hope this helps you sort out your ideas. Have a good weekend!
Kristi
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