CASE STUDY: The River Exe, Devon - AQA Geography, A-Level

The River Exe...

...flows for 82.7km from its source in Exmoor.

What are 3 Physical Characteristics of the River Exe?

1. Area of upper catchment = 601km²

2. Maximum elevation = 514m

3. Lowest elevation = 26m

Describe the Geology of the River Exe

84.4% of the catchment is underlain by impermeable rocks - predominantly sandstones.

What is the land-use around the River Exe Basin?

* 67% agricultural grassland.

* 15% woodland.

* 3% moors and peat bogs.

Describe and Explain the Runoff levels of the River Exe Catchment

* Runoff = 65% of water balance (high)

* Runoff is due to the impermeable nature of the

bed rock = reduced percolation and base flow.

* Drainage ditches on Exmoor reduce soil water storage.

What 2 projects affected the Water Cycle and Balance?

1. Construction of Wimbleball Reservoir.

2. Restoration of Peatland on Exmoor.

When was the Wimbleball Reservoir created?

1997.

Describe the Wimbleball Reservoir (4 points)

* SA = 150 hectares.

* Supplies water to Exmoor and East Devon.

* Regulates water flow ensuring a constantly steady regime.

* Prevents peaks and troughs of water discharge - reducing flood risk.

What effects did the Drainage Ditches have on the Water?

They increased the spread of water flow to the river, reducing water quality as more silt was carried downstream.

What is the Exmoor Mires Project?

Restores peat bogs by blockage drainage ditches.

What are the 5 things the Exmoor Mires Project does?

1. Increases water content.

2. returns ground to natural saturated, boggy conditions.

3. Helps retain carbon within the peat.

4. Means more water storage in upper catchment.

5. Improves water quality.