The BCWWA regularly responds to policy and regulatory updates on behalf of its members. The Association's Drinking Water Technical Advisory Committee is currently reviewing the three consultations underway:
1. Enterococci bacteria as indicators in Canadian drinking water supplies
Enterococci are a bacteriological indicator of faecal contamination that can be used in assessing drinking water safety. They can be included in a drinking water monitoring program to provide information on the quality of the source water, the adequacy of treatment and the delivery of safe drinking water to the consumer.
Health Canada recently completed its review of enterococci in drinking water. The guidance document describes the significance, sampling and treatment considerations for the use of enterococci as a bacteriological indicator in the context of drinking water quality and safety.
2. Chloramines in drinking water
The term "chloramines" refers to both inorganic and organic chloramines. This document focuses on inorganic chloramines, which consist of monochloramine, dichloramine and trichloramine. Unless specified otherwise, the term "chloramines" will refer to inorganic chloramines throughout the document.
Chloramines are found in drinking water mainly as a result of treatment, either intentionally as a disinfectant in the distribution system, or unintentionally as a by-product of the chlorination of drinking water in the presence of natural ammonia. As monochloramine is more stable and provides longer-lasting disinfection, it is commonly used in the distribution system, whereas chlorine is more effective at disinfecting water in the treatment plant. Chloramines have also been used in the distribution system to help reduce formation of common disinfection by-products such as trihalomethanes and haloacetic acids. However, chloramines also react with natural organic matter to form other disinfection by-products.
All drinking water supplies should be disinfected, unless specifically exempted by the responsible authority. Disinfection is an essential component of public drinking water treatment; the health risks associated with disinfection by-products are much less than the risks from consuming water that has not been adequately disinfected. Most Canadian drinking water supplies maintain a chloramine residual below 4 mg/L in the distribution system.
The guideline technical document focuses on the health effects related to exposure to chloramines in drinking water supplies, also taking in consideration taste and odour concerns. It does not review the benefits or the processes of chloramination; nor does it assess the health risks related to exposure to by-products formed as a result of the chloramination process. The Federal-Provincial-Territorial Committee on Drinking Water has determined that an aesthetic objective is not necessary, since levels commonly found in drinking water are within an acceptable range for taste and odour, and since protection of consumers from microbial health risks is paramount.
3. Barium in drinking water
Barium occurs in various compounds in the environment either naturally or from human activities. While the main use of barium is as a drilling fluid additive in oil and gas exploration, it is also used as a contrast agent in X-ray diagnostic tests and in a wide array of products, including plastics, rubbers, paint, glass, carpets, ceramics, sealants, furniture, fertilizers and pesticides.
Naturally occurring barium can be found in most types of rocks and can enter surface and groundwater by leaching and eroding from sedimentary rocks. A total of over 20 radioactive barium isotopes, with various degrees of stability and radioactivity, have been identified in the environment. However, the focus of this document is limited to barium’s chemical properties.
The guideline technical document reviews and assesses all identified health risks associated with barium in drinking water. It assesses new studies and approaches and takes into consideration the availability of appropriate treatment technology. Based on this review, the proposed guideline for barium in drinking water is a maximum acceptable concentration of 2.0 mg/L.
About public consultations
The public consultations are intended for scientific or technical audiences who focus on drinking water, including:
- regulatory agencies
- academic communities
- health protection agencies
- public drinking water utilities, such as drinking water treatment plants
If you are interested in providing comments for consideration in any or all of the three BCWWA responses to the guidelines under review, please send your comments to Jodi Garwood at firstname.lastname@example.org by January 4, 2019. In addition to providing input to the BCWWA, we also recommend providing your comments directly to the Water and Air Quality Bureau at Health Canada via email at email@example.com.