Drainage basins of Wales and the UK

Drainage Basins in the UK

Drainage basins are geographical areas where all surface water flows into a single river system. They play a large role in the UK’s landscape due to the country’s high annual rainfall.
Boundaries of a drainage basin, known as watersheds, consist of high areas that separate different drainage basins.
The catchment area encompasses all areas where water can flow into a river. This includes water that seeps through the ground or is collected after rainfall.

The Structure of a Drainage Basin

Important components include the main river that collects all the water, the tributaries that feed into the river, and the source where the river originates.
Parts of the basin where water collects before entering the river are called pools and those where the water exits are called riffles.
The point where the river flows into the sea or another body of water is called the mouth of the river.

The River Severn Basin in Wales and the Upper Thames Basin

The River Severn drainage basin is one of the largest in the UK, encompassing over 11,500 square kilometres, and features diverse physical geography, with both highland and lowland areas.
Rainwater flows from high areas in mid-Wales, into tributaries, and ultimately into the River Severn, which empties into the Bristol Channel.
The Upper Thames basin covers a portion of the UK’s southeast. Its headwaters are near the village of Kemble in Gloucestershire, and it features a range of landscapes from rural countryside to urban areas.
Processes such as surface run-off, throughflow, and groundwater flow contribute to the movement of water within these drainage basins.

The Role of Human Activities

Human activities greatly influence the properties of drainage basins, particularly through urbanisation and deforestation.
Construction such as building roads or housing can increase surface run-off by reducing the amount of permeable ground available to absorb rainwater.
Deforestation removes trees that would normally contribute to interception, resulting in greater surface run-off and potential for flooding.
Human efforts to manage drainage basins vary. They include building dams for trapping water and constructing embankments to strengthen river banks.

Remember, understanding the geographical and human factors that shape drainage basins is essential in studying how landscapes evolve and managing potential environmental issues.