WHAT IS A WATERSHED?

Wherever you live, you live in a watershed.

A watershed is the area of land that carries water from the land after rain falls and snow melts through the soil, groundwaters, creeks and streams making its way into larger rivers and eventually the ocean. Because water flows downhill, the watershed boundaries are most always located on the top of hills or mountains. 

Any changes that are made to land located in a watershed will affect the watershed. These changes could include such things as replacing forests and prairies with housing developments. This would decrease the amount of water that seeps into the ground causing water to flow more quickly over streets and sidewalks into street drains that empty into rivers. Flooding is often more severe in developed areas because water flows faster over these areas as opposed to being slowly absorbed and filtered through soil. 

As rainwater drains into rivers it picks up pollutants such as chemicals, salt and oil which is carried to the river. These pollutants come from a large area of the landscape and you cannot identify exactly where they are coming from, such as one person or a company. This type of pollution is called non-point source pollution. The other type of pollution is point source pollution. The source of this pollution can usually be traced to a source, such as a sewage pipe or culvert. Non-point source pollution is more difficult to regulate than point source pollution, and it will take everyone who lives in the watershed to make a conscious choice to change their behaviours to reduce or stop non-point source pollution.


Water in Alberta

Today, irrigated agricultural production accounts for about 18% to 20% of Alberta's total agricultural production.

20% of the world's drinking water is in Canada, but Alberta accounts for only 2.2% of Canada’s fresh water.

While 80% of Alberta's water supply lies in the Northern part of the province, 80% of our water demand comes from the Southern half of the province.

Alberta is estimated to have much more groundwater than surface water. However, only 0.01% of this groundwater is believed to be recoverable.

There is a finite amount of potable (drinkable) water in the province (97.5% comes from surface water and 2.5% comes from groundwater).

In Alberta, approximately two million people get their drinking water from large municipal systems. Approximately 400,000 Albertans get their water from smaller water treatment plants. The remaining 600,000 Albertans obtain their water from private systems such as wells, water co-ops or by hauling.

In southern Alberta, more than 505 000 hectares of land (just 4% of the total and that can be cultivated in Alberta) are serviced by 13 irrigation districts. These irrigation networks are used by agriculture and they also supply nearly 50 communities with water for domestic use.

Alberta has an agreement with Saskatchewan that guarantees that 50% of the water in each of the shared, major river basins, must be allowed to flow into Saskatchewan. This agreement is called an apportionment agreement.

Alberta shares borders with British Columbia, Northwest Territories, Saskatchewan and Montana. Currently, apportionment agreements only exist with Saskatchewan and Montana.

In Alberta, we use a priority system based on principles of prior allocation rights as well as policies adapted for special situations. This principle, which has been in existence since 1894, means that water rights are prioritized according to how senior the license is, regardless of the use. The older the license, the higher that user is on the priority list.

The theory of the principle is that it protects an existing user’s rights from those who come after them and is the best way to allow for orderly development. For example, during a drought, a farmer with a senior license may have access to water for irrigation, while at the same time a city with a more recently issued license may be forced to ask residents to ration water.

Sources: Alberta Environment, Alberta Water for Life Strategy, and Environment Canada. For more Alberta Water Facts, visit Alberta Water Smart.

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