The River Exe, Devon Case Study

Question 1

Where is the river Exe located and how far does it flow from its source?

Answer 1

It is located in Exmoor, Devon and flows for 82.7km from its source.

Question 2

What are 3 physical characteristics of the River Exe?

Answer 2

1)Area of upper catchment=601km2 (Steep relief)
2)Maximum elevation=514m in North
3)Lowest elevation=26m in South

Question 3

Describe the geology of the River Exe?

Answer 3

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

Question 4

What is the land use around the River Exe basin?

Answer 4

-67% agricultural grassland
-15% woodland and arable farming
-3% moors and peat bogs

Question 5

Describe and explain the runoff levels within the River Exe catchment?

Answer 5

-Runoff = 65% of water balance (high)
-Runoff is due to the impermeable nature of the bedrock = reduced percolation and base flow.
-drainage ditches on Exmoor reduce soil water storage.

Question 6

What 2 projects affected the Water Cycle and Balance?

Answer 6

1)Construction of the Wimbleball Reservoir.
2)the restoration of peatland on Exmoor.

Question 7

When was the Wimbleball reservoir created?

Answer 7

1979

Question 8

Describe the Wimbleball Reservoir (5 points)

Answer 8

-Surface area = 150 hectares
-Supplies water to Exmoor and East Devon.
-Regulates waterr flow ensuringng a constantly steady regime.
-Prevents peaks and troughs of water discharge - reducing flood risk.
-located on one of the river Exe’s upland tributaries called the river Handeo

Question 9

What effects did the drainage ditches have on the water cycle?

Answer 9

They increased the spread of water flow to the river Exe, which reduces water quality as more slit was carried downstream.

Question 10

What is the Exmoor Mires Project?

Answer 10

Restoration of peat bogs by blocking drainage ditches.

Question 11

What are 5 things the Exmoor Mires Project does?

Answer 11

-Increase soil water storage capacity.
-Returns ground to natural saturated, boggy conditions.
-Helps retain carbon within the peat.
-Means more water storage in upper catchment.
-Improves water quality.