From Source To Tap - The Multi-Barrier Approach To Safe Drinking Water

Guidelines, Standards & Objectives

Guidelines, standards and objectives provide utility managers and system owners with drinking water quality targets to strive to achieve within their systems. These targets are closely linked to monitoring results, as the latter tell utility managers and system owners how close they are to meeting targets and help them make decisions about their water system. In some jurisdictions, meeting these targets is mandatory.

Because raw water (including ground and surface waters) may support a variety of beneficial uses, such as aquatic life and agriculture, a number of guidelines¹ have been developed to protect these uses; these guidelines may help protect or enhance the quality of water used as a source for drinking water even though they are not specifically developed for this reason.

Since it is prudent to protect raw water supplies to ensure they are maintained as good sources of drinking water, these guidelines, and those developed for source waters, may be used as benchmarks to develop protection measures or corrective actions in watersheds and around wells and to measure the success of management practices. Watershed management encompasses both regulatory and non-regulatory strategies. The success of watershed management is based on agreed-upon, achievable, environmental quality objectives.

The development and implementation of source water quality guidelines not already in place would add a new dimension to source protection efforts and would complement the multi-barrier approach.

For drinking water, the Guidelines for Canadian Drinking Water Quality² set out the basic parameters all water systems should strive for in order to deliver the cleanest, safest, and most reliable drinking water to consumers. These guidelines apply to water destined for human consumption and are developed for select physical, chemical, microbiological, and radiological parameters. The most important guidelines deal with microbiological quality and help ensure the risk of exposure to disease-causing organisms in drinking water is minimized.

¹ The guideline values for other beneficial uses are posted on the website of the Canadian Council of Ministers of Environment (www.ccme.ca)

² All values and supporting documentation for the Guidelines for Canadian Drinking Water Quality are posted on Health Canada's water quality website (www.hc-sc.gc.ca/waterquality).