Many communities in Ontario draw their drinking water directly from the Great Lakes, large rivers and lakes. Water is transported through an intake pipe directly from a lake or river into a water treatment system. Protecting a surface water intake means protecting the surrounding water around the intake and the land that is immediately near the water. This area of water and land is known as an intake protection zone (IPZ). It is divided in to 3 zones, but only the first two currently have policies which apply to them. The area of water and land within an intake protection zone is determined by a variety of factors such as the amount of time it would take any material spilled in or near the river to flow downstream to the water intake. A fast or slow flowing river can change the area of an intake protection zone significantly.
Intake Protection Zone 1 (IPZ‐1) is the area immediately adjacent to the intake. This zone is considered the most vulnerable area for surface water intakes due to its proximity to the intake, contaminants of concern entering this area would experience little to no dilution before reaching the intake.
The Intake Protection Zone 2 (IPZ‐2) acts as a secondary protective zone that generally extends upstream of the IPZ‐1. The IPZ‐2 is defined as the area within and around a surface water body that may contribute water to an intake within a 2 hour time of travel, determined by water treatment plant operators to be sufficient for responding to a contamination event.