Water Quality / Turbidity Index

Turbidity is the cloudiness or haziness of a fluid caused by large numbers of individual particles that are generally invisible to the naked eye, similar to smoke in air. The measurement of turbidity is a key test of water quality.

Interior Health has the following ratings for turbidity levels related to water quality.
GOOD - 0 to 1 NTU
FAIR - 1 to 5 NTU 
POOR -  5 NTU and above 

Your water supplier will issue a WQA if turbidity levels exceed 1 NTU. Children, the elderly, people with weakened immune systems, and anyone seeking additional protection will be advised to drink boiled water or a safe alternative. Ongoing information will be available on participating water suppliers’ websites and through the media.

Your water supplier will issue a BWN if turbidity levels exceed 5 NTU. All users will be advised to drink boiled water or a safe alternative. Ongoing information will be available on participating water suppliers’ websites and through the media.

Turbidity is not so much a health concern as an indicator of health risk. Science has proven that as turbidity increases, the risk for gastrointestinal illness also increases—particularly for at-risk populations such as newborns, the elderly, and people with weakened immune systems (e.g. those with HIV/Aids, undergoing chemotherapy, or taking anti-rejection drugs following a transplant).