River Eden

Question 1

Where is the River Eden located?

Answer 1

The River Eden drainage basin is located in North West England between the mountains of the Lake district and the Pennines

Question 2

What is River Eden’s river mouth?

Answer 2

Flows North West to Solway Firth on the Scottish boarder

Question 3

What are some river basin characteristics?

Answer 3

Largely rural but the river flows through the city of Carlisle

Question 4

What are the upland areas in the River Eden?

Answer 4

The drain into the River Eden experiences extreme weather than flooding downstream

Question 5

Why is Carlisle vulnerable?

Answer 5

Carlisle is located at the confluence of 3 rivers; the River Eden, the River Petteril and River Caldew

Question 6

What are characteristics of the Eden basin?

Answer 6

• Relief of the Eden basin
• Shape of the Eden basin
• Rock type

Question 7

How does the relief of the Eden basin affect the River Eden?

Answer 7

• Mountainous terrain encourages orographic rainfall, where the rainfall is higher than average as the soil is saturated

Question 8

How does the shape of the Eden basin affect the River Eden?

Answer 8

• The Eden basin is long and narrow, increase’s lag time
• The slope is steep which decrease’s lag time and increase peak discharge

Question 9

How does the rock type affect the River Eden?

Answer 9

• The high ground in the West of the basin is igneous rock which is impermeable, infiltration is slow and surface runoff is high, decreasing lag time
• The lower ground is made of limestone and sandstone which is permeable, infiltration is fast and surface runoff is low, lag time increase’s and water store increase’s

Question 10

What changes to the River Eden’s drainage basin affects flood risk?

Answer 10

• Intensive farming
• Grazing in upland areas
• Construction
• New development built on floodplains near Carlisle
• Deforestation
• Climate change
• Precipitation

Question 11

How does intensive farming affect flood risk?

Answer 11

• Intensive farming is the result of the compaction of soil through heavy machinery and livestock
• E.g. Between 2000 and 2009 there was a 30% increase in cattle in the Eden Valley, so the land compacted increased. This decreased infiltration and increase surface runoff, decreasing lag time and increase peak discharge

Question 12

How does grazing in upland areas affect flood risk?

Answer 12

• E.g. Hill sheep farming increases soil compaction, decreasing the amount of vegetation intercepting rainfall so more water reaches the rivder. More surface runoff, increase water levels in rivers during heavy rainfall, increase flood risk

Question 13

How does construction affect flood risk?

Answer 13

• New housing estates built in Carlisle
• E.g. Eden Gate development to develop a ‘garden village’ including 10,000 new homes. Surfaces are impermeable and decreases infiltrationand increase surface runoff

Question 14

How does the development built in floodplains near Carlisle affect flood risk?

Answer 14

• Increase’s risk of flooding of property and requires a constuction of flood defences to protect homes
• Building on floodplains cause flooding downstream as water infiltrates on floodplains

Question 15

How does deforestation affect flood risk?

Answer 15

• Tress intercept infiltration and decrease surface runoff, so fewer trees means an increase in surface runoff, flashier flood hydrograph, increase risk of flooding

Question 16

How does climate change affect flood risk?

Answer 16

• Increased winter rainfall in the Eden basin increases surface runoff and flood risk

Question 17

How does precipitation affect flood risk?

Answer 17

• During heavy storms with lots of water entering the river over a short term results in higher discharge
• Lag time is greater if precipitation is snow as it takes time to melt
• If snow melts, there is a higher discharge. Antecedent rainfall
• During the winter seasons, there is more storm events which increase rainfall, saturated soil for a longer time, shorter lag time, high discharge

Question 18

When did Storm Desmond happen?

Answer 18

• December 2015, Storm Desmond caused severe flooding in Cumbria and the Eden basin

Question 19

What were the impacts of Storm Desmond?

Answer 19

• More than 2000 properties were flooded in Carlisle leavinf many people homeless

Question 20

What are some stats for Storm Desmond?

Answer 20

• Record rainfall in Cumbria: 262.2 millimetres fell in 48 hours from the 4th to 6th of December. This was 50 mm higher than average.

Question 21

What are some mitigation strategies to reduce flooding?

Answer 21

• Afforestation: Near Dalston, 1000 trees were planted to reduce flooding.
• As trees intercept and absorb rainfall, reduces surface runoff
• Flood defences: 10 km of raised flood defences built along River Eden. Reduce flooding.