The Course of a River

The course of a river:

The journey of river from source to mouth is sometimes called the course of the river. The course of a river can be divided into three main sections:

• upper course
• middle course
• lower course

Rivers always flow downwards from highland areas to lowland areas, through the upper, middle, and finally the lower course.

Diagram showing the course of a river

Upper Course of a River:

A river with an extremely low discharge during the winter season at Mt Sorak National Park, South Korea. Note the vegetated island bar in the middle of the river channel. The river is also flowing within a v-shaped valley at the upper course.

Middle Course of a River

The river begins to meander. It also flows through a wider v-shaped valley.

Lower Course of a River

This is a photograph of the lower course of the Dahadinni River in Canada. As can be seen from the photograph, the river is carrying a lot of sediment (river load). Parts of the river are already silted up. "The observed flow in the Dahadinni River is much smaller than the overall width of the channel. This reflects the occurrence of a recent, severe flood, which caused a major widening of the river channel." (Geological Survey of Canada)

The river is flowing past an area with low gradient.