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For information on groundwater monitoring please go to the: Watershed Report Card

Groundwater is subsurface water that occurs beneath the water table in soils and geological formations that are fully saturated. It is the water below the water table contained in void spaces (pore spaces between rock and soil particles, or bedrock fractures). It is water occurring in the zone of saturation in an aquifer or soil.

Groundwater discharge
Groundwater discharge is the function of a wetland to accept subsurface water and hold it for release over long periods of time.

Groundwater flow 
Groundwater flow is the rate of groundwater movement through the subsurface.

Groundwater recharge 
Groundwater recharge is the inflow of water to a ground water reservoir from the surface. Infiltration of precipitation and its movement to the water table is one form of natural recharge.

Groundwater recharge area
A groundwater recharge area is an area where an aquifer is replenished from:

(a) Natural processes, such as the infiltration of rainfall and snowmelt and the seepage of surface water from lakes, streams and wetlands;

(b) From human interventions, such as the use of storm water management systems, and;

(c) whose recharge rate exceeds a specified threshold.

A significant groundwater recharge area (SGRA) is one of four vulnerable areas identified in Ontario’s Clean Water Act, 2006.

Also see and

Provincial Groundwater Monitoring Network (PGMN)

The Ontario Ministry of the Environment, Conservation and Parks (MECP) has been partnering with conservation authorities and their member municipalities on a provincial groundwater monitoring network (PGMN) since 2000.  

The PGMN has been established to collect and maintain ambient (baseline) groundwater level and quality information from more than 450 wells, representing major aquifers across the province. Data from the monitoring network provides an early indicator for potential emerging issues such as climate change, water usage demand changes, and changes to water quality from both human-made and natural causes.

Ausable Bayfield Conservation Authority (ABCA) currently monitors water levels and quality at 16 locations across the ABCA watersheds.