The Water Cycle

Water in Motion!

Water moves continuously through our natural environment in a cycle.

We pick up the water cycle with rain or melting snow, which in reaching land:

• Flows to rivers, creeks and lakes
• Seeps into the ground and wetlands where it is stored

Plants absorb this water, and animals, including us, drink it.

This water moves again! It may evaporate (into the air) from the surface of lakes, aided by the sun. It is released by plants and animals. Water also filters in the ground and moves through soil to feed our lakes, rivers and wetlands.

The evaporated water, as moisture, is carried by air. It rises, condenses to form clouds, and then is released (as rain or snow) to fall to earth once again.

Water Feeds Life

Water supplies the needs of all life. Its flow through the landscape of a river’s drainage area, or watershed, linking the natural features and communities of the watershed together. Within a watershed, everything is connected to everything else.

We are as much a part of this system as are the trees, animals and fish. We must take care of the water.

Surface Water and Groundwater

Surface water is the water that flows on the surface of the earth. Groundwater is found underground in the cracks and spaces in rocks, soils and sands.

Diving Deeper… Groundwater

Groundwater is stored in, and moves slowly through, aquifers. An aquifer is an underground layer of rock or sands and gravels that can hold water. As a “bank” of water, aquifers can store more or less water depending on the season and recent rains. We sometimes refer to the top of the aquifer as the water table. The water table can rise after spring melt or heavy rains, and fall when less water is available (e.g., dry periods).

In our area, and with time, groundwater flows into creeks, a river or even into Lake Ontario itself.

In towns and rural communities in the Credit River Watershed, drinking water comes from groundwater pumped from underground wells. In our urban areas, Lake Ontario is the source of drinking water.

Water’s Exit from Our Watershed

Water that flows into the watershed also leaves our watershed by four natural means:

1. Evaporation from lakes, rivers and soil
2. Released by plants and trees, called transpiration
3. Creek and river runoff to Lake Ontario
4. Discharges of groundwater into a river or creek or into Lake Ontario
5. Flows underground into a neighbouring watershed

Our Impacts to the Water Cycle

Human activities affect the water cycle.

We use water for our day-to-day needs:

• Surface and groundwater are our drinking water sources
• We use water to irrigate our crops and golf courses
• Many industrial processes require water such as quarries

In our urban areas, paved surfaces like roads, parking lots and buildings change how water moves over the landscape. Natural drainage is often replaced by curbs and gutters along roadways and storm sewer pipes which can result in water flowing quickly into our local rivers and streams. This leads to:

• Increased risk of flooding
• Higher rates of erosion on stream and riverbanks
• Increased water temperature in streams, rivers and lakes
• Impacts to fish and other animals living in water

As rain and snowmelt falls on the ground, it becomes stormwater and can pick up pollutants such as:

• Pesticides, sediment and fertilizers from farm fields, lawns and gardens
• Water foul and pet waste
• Salt, oil and gas from parking lots, sidewalks and roads

Take Action to Reduce our Impacts

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