The river exe

Question 1

where is the river exe

Answer 1

the river exe flows for 82km from the hills in exmoore to the sea at exmoor

Question 2

physical characteristics of the catchment area

Answer 2

the area of the upper catchment is around 600km2. Maximum elevation is 514m

Question 3

Geology

Answer 3

Approx 85% of the catchment is underlain by impermeable rock (sandstone)

Question 4

Land Use

Answer 4

Mostly agricultural grassland (67%) some woodland and arable farmland. In the north there are peatlands and moors

Question 5

History (Exmoor Mires)

Answer 5

Government subsidies paid to peatland lenders to drain the land, to use it as agriculture (1960s)

Question 6

Why is runoff high in the drainage basin of the river Exe?

Answer 6

• Main geology is impermeable sandstone
• Land use is arable, ploughed field speed up water
• Steep relief
• Drainage ditches

Question 7

How does the Wimbleball reservoir reduce the risk of flooding?

Answer 7

creates a steady flow of water throughout the year, stops the peaks and troughs from overloading the river

Question 8

How did the drainage ditches affect the river?

Answer 8

Increased runoff meant that discharge increased, silt from the land built up and deceased the river’s carrying ability

Question 9

What was the exmoor mires project?

Answer 9

project that aims to restore the peatland to its original saturated state by filling in the drainage ditches

Question 10

how does the exmoor mires project benefit the area

Answer 10

• more stable river flow, less runoff
• less sediment in the river
• water is cleaner, less expensive to treat
• re- wetting of peat allows carbon to stored