Urban Impacts on Water Quality and Supply

Water quality is a major environmental issue. Society has been quick to point fingers at industry, agriculture, and other land-disturbing activities as the culprits of groundwater and surface water contamination.

Soil eroded from lawns and gardens carry many contaminants to surface water. In fact, a single building site can lose four truckloads of soil in one storm. Washed from the sites into storm drains this sediment is eventually deposited into waterways.

Normally, the contribution of water pollutants from a homeowner's lawn is small. However, when millions of small inputs are added together, the impact on water quality may be significant. Even cars that are washed in the streets can pollute our water. The soapy water that runs off cars into the gutters goes into the storm water drain and unlike the water that enters the sewers, goes untreated before it is discharged into our waterways.

When an accident occurs on a local highway spilling gallons of chemicals, where does it go? The salt spread on the roads in the winter is effective but what happens when it is washed into our waterways year after year?

What about the raw sewage on its way to the treatment plants? Are the thousands of miles of sewer lines being monitored? Could they be leaky? Domestic sewage, municipal landfills and sewage treatment plants cause concern for a great number of people. In places like Walkerton Ontario, lives have been lost due to poor management of these facilities. How carefully are these facilities being monitored in our own communities?

Your task is to investigate the urban impacts on our water systems and make recommendations about what needs to be done to address them. It is important to realize that a key to minimizing our collective impact on our water systems is to reduce the quantity of pollutants entering them in the first place.


Landfill site

Municipal wastewater

Water meters

Fertilizer/Nutrient pollution


Soil erosion

Car washing effects/phosphate effects


Measuring water quality

Calgary Waterworks

Health Canada Guides for Canadian Drinking Water

Alberta Environmental Protection and Enhancement Act

General Resources on Water

©2002 Golden Hills School Division #75
©2002 The Galileo Educational Network Association