Water Drainage Systems

Water Drainage Systems

by Thomas Poelstra

Rivers​

​Rivers are important due to their use as transportation routes, water supply, and as a source of food. The St. Lawrence River was crucial to the development of Canada. It was used as a transportation method for the first Nations people, and the European explorers who came from Europe to explore the land. In New France, plots of land were long and narrow to fit as many settlements as possible along the St. Lawrence. As Canada developed as a country many towns and cities were built on or near rivers and lakes e.g. Winnipeg.

Open Ended

Why are rivers important?

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​River systems are a network of other streams and lakes called tributaries that eventually flow into one river such as St. Lawrence River. River systems can be found all over the world and flow from high to low ground. The longest river system in the world is the Nile located in Egypt. Rivers have a beginning called a headwater, and an end called the mouth, which drains the river into a larger body of water. Canadian rivers maintain their water level from melting snow or rainfall depending on the time of the year.

Open Ended

What is a river system? Give an example of a Canadian river system.

Dendritic Drainage​

​As rivers move they erode two different patterns (Dendritic and Trellis) into the earth depending on the surrounding landforms and the environment. Soft rocks are easily eroded by water whereas hard rocks maintain their shape longer and are harder to erode. This is the most occurring drainage pattern. As the rivers flow over rocks a tree-like pattern will be created into the landforms. It resembles a tree because of its main area (tree truck) and then smaller lines that run off the main line (branches).

Trellis Drainage Pattern​

​ This is a less common drainage pattern. If the river flows over both hard and soft rocks it will create a rectangular drainage pattern with one main line and perpendicular lines that run off the main line.

​Drainage Basins

​Water drains from the highest to the lowest point of land. In North America there are five major drainage areas: Arctic Ocean Drainage, Hudson Bay Drainage, Atlantic Ocean Drainage, Gulf of Mexico Drainage and Pacific Ocean Drainage. These drainage areas drain into one of the three North American oceans (Arctic, Atlantic, Pacific) depending on the location of the drainage area.

Open Ended

Write the 5 major drainage areas in North America. Which oceans do they drain into?

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​A drainage basin is the whole area that drains into one river system. In Ontario, the St. Lawrence basin contains the five Great Lakes and several rivers. An issue that occurs within drainage basin is pollution, because all of the water is interconnected. If one area of water becomes contaminated it will eventually flow into other areas because they all drain into one area. This pollution can cause damage to aquatic life and cause health issues for the residents living around the water

Open Ended

What is a drainage basin?