River Dee case study

Question 1

Where is the source of the Dee

Answer 1

Dduallt in Snowdonia

Question 2

Describe the courses of the river Dee?

Answer 2

Uppercourse:
-Geology is made up of hard igneous rocks
-V shaped valley
-large angular rocks in bed load
-Slow river velocity
-3000mm precipitations
Middlecourse:
-Higher discharge due to tributaries
-Floodplains and meanders
-Lateral erosion causing some width
Lower course:
-Flows through softer sedimentary rocks like sandstone
-main settlement is Chester
-Estuary where river becomes tidal
-mouth on irish sea seperating the wirral
-Highest discharge and highest velocity due to less friction between the beds and the banks
-Smallest bedload size

Question 3

How long is the Dee?

Answer 3

113km

Question 4

Key facts about uses of the Dee:

Answer 4

94% catchment is rural
approximately 3 million rely on the river for water
supports habitats
important for commercial fishing
snowdonia national park are popular for recreation

Question 5

What human factors are changing the river dee?

Answer 5

In 1960s dam were built to keep up with demand for water, 2 reservoirs made :LLyn celyn 327k cm3 and Llyn Brenig 800k cm3 a day and hold 60 million cm3 in total.They can reduce discharge of river downstream
In Bangor on dee in the middle course, earth embankments protect farmland and properties from flooding. Land drainage pumping system at Worthernbury Meadows removes excess flood waters.
In Chester the river experiences channelisation where the banks have been artificially straightened to improve navigation. They have increased velocity and discharge.

Question 6

What physical factors are affecting the Dee?

Answer 6

Drought
Intensity of rainfall
Variable weather due to climate change