Well Aware | How To Be



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Compared to surface water, groundwater usually moves very slowly – from a few millimetres to a few metres a day. Groundwater affects the quality and quantity of surface water where it discharges into streams, rivers, wetlands, and lakes.

Surface water zones

Graphic: Ontario Ministry of the Environment

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The results of my Well Aware home visit were amazing. The process took over an hour onsite and we discussed all aspects of my well and septic system. I received a comprehensive report with some specific recommendations that may well have saved me thousands of dollars.

I am happy to report that my entire family is now drinking our own well water, which has been tested to be safe to drink.

That news is as welcome as a tall glass of water on a hot day.

A.Killins, 2011 GSA participant

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Your well receives water from an underground water source called groundwater.

Groundwater originates from surface water and precipitation, including rain and melting snow. Water infiltrates the earth over a period of time from days to thousands of years. Saturated layers below the water table that store and transmit significant quantities of groundwater – e.g., enough to supply a well – are called aquifers.


Groundwater flows

It is impossible to determine the direction of groundwater flow based on surface features alone. However, we do know that water in an aquifer near a pumping well will most likely flow toward the well. The risk of well water contamination is greatest when the contaminant is close to the well. Yet, some contaminants have been known to spread over several kilometres.

aquifer recharge

Graphic: Ontario Ministry of the Environment

Local geology

The type of soil and rock can influence the speed at which surface water infiltrates the groundwater that your well taps into. Your well is at lower risk if these materials effectively prevent surface contaminants from reaching the aquifer. For example, thick deposits of fine soils like clay loams or silty clay can be more effective in preventing contamination from nearby surface activities than coarse soils like sand and gravel.


water cycle