Six Year Financial Plan Archive
Drinking Water Report Archive
Water Quality Reports
Glossary for Quarterly Reports
MAC (Maximum Acceptable Concentration)
The MAC is established for parameters which when present above a certain concentration, have known or suspected adverse health effects. The length of time the MAC can be exceeded without health effects will depend on the nature and concentration of the parameter.
IMAC (Interim Maximum Acceptable Concentration)
The IMAC is established for parameters either when there is sufficient toxicological data to establish a MAC with reasonable certainty, or when it is not feasible, for practical reasons, to establish a MAC at the desired level.
AO (Aesthetic Objective)
AOs are established for parameters that may impair the taste, odour or colour of water or which may interfere with good control practices. For certain parameters, both aesthetic objectives and health-related MACs have been derived.
OG (Operational Guidelines)
OGs are established for parameters that, if not controlled, may negatively effect the efficient and effective treatment, disinfection and distribution of the water.