Description: 20-Apr-21. Zone of Critical Concern (ZCC) – ZCC for a public surface water supply source and for a public surface water influenced groundwater supply source is a corridor along streams within a watershed that warrants detailed scrutiny due to its proximity to the surface water intake and the intake’s susceptibility to potential contaminants within that corridor. The ZCC is determined using a mathematical model that accounts for stream flows, gradient and area topography. The length of the ZCC is based on a five-hour time-of-travel of water in the streams to the water intake.
Description: 20-Apr-21. Zone of Peripheral Concern (ZPC) – ZPC for a public surface water supply source and for a public surface water influenced groundwater supply source is a corridor along streams within a watershed that warrants scrutiny due to its proximity to the surface water intake and the intake’s susceptibility to potential contaminants within that corridor. The ZPC is determined using a mathematical model that accounts for stream flows, gradient and area topography. The length of the ZPC is based on an additional five-hour time-of-travel of water in the streams beyond the perimeter of the ZCC, which creates a protection zone of ten (10) hours above the water intake.
Description: 20-Apr-21. Wellhead Protection Area (WHPA) - The surface and subsurface area surrounding a water well or wellfield, supplying a public water system, through which contaminants are reasonably likely to move toward and reach such water well or wellfield.
Description: 20-Apr-21. These are combined protection areas where an intake has a ZCC, ZPC and WHPA protection areas. This is the combination of all of these.