Flood mitigation

Question 1

WHat is the main interest of flood mitigation?

Answer 1

Flooding at a particular place to prevent or mitigate it

Question 2

What is mitigation wanting to control?

Answer 2

Cant control precipitation but can control how much preipitation is translated into a flood event (temporal pattern)

Question 3

What canchnage the rate of run-off?

Answer 3

Interception
Evapotranspiration (long term instead of flash)
Infiltration (vegetation uptake)

Question 4

What can be done to alter the amount of water that can be carried by the channel?

Answer 4

INcrease carrying capacity or things that can contain or protect rivers

Question 5

WHat can be done in the upper hill slopes of a catchment to mitigate flooding?

Answer 5

Involves landuse change (increasing forest cover)

Disconnected in time and space from area of intrest

Question 6

What is being looked at in the middle part of the catchment to mitigate for floods?

Answer 6

slowing down flow
temporary storage (allowinf river to flow onto floodplain for storage)
Artificial

Question 7

What can be done in the lower part of the cathment to mitigate flooding?

Answer 7

Strutural and mitigate against effects that have already happened

Area of intrest

Question 8

Where is the brunt of the econmoic impact for flooding?

Answer 8

USually the lower part of the catchment

Question 9

What is the problem with flood defences in the lower catchment?

Answer 9

Have to be built bigger to protect for large events but these are realtivly infrequent so defences have t be lived with inbetween so design to be less intrusive needed

Question 10

What flood defence type in the lower catchment is gaining traction?

Answer 10

Protection of individual buildings to limit or prevent damage (non-return valve on toilet, outside temporant flood gates)

Question 11

What is unsustainble for flood defences?

Answer 11

Making them higher and a larger extent
Increases complacency by population

Question 12

What does flooding legislation do?

Answer 12

put pressure on local authorities to try and mitigate further dmasgr to the water course (move from more extensive defences)

Question 13

How can the mid catchment be altered to help mitigation?

Answer 13

Using natural flood plain for storage (deep steep river channels stop flooding in plain)
River restoration (be more meandering so water can spill onto plain)- small channels log jams or beaver dams

Question 14

How do floodplains and wet woodlands help mitigate flooding downstream?

Answer 14

Slow water passage (complex surface/ topography then just grassland - lowering flood peak)
Store water

Question 15

How can the upper cathment be incorporated into flood mitigation?

Answer 15

Be a sponge (take water out of flood event and store in upper area- vegetation interception)
Woodland and logjams slow water passage in headwater of channel network
Bunds- temporary resevoir (earth dam slowly releases water)

Question 16

Where are the flood mitigation strategies most effective?

Answer 16

Smaller scale events in smaller catchments

Question 17

What are the limits to mitigation working in large catchments?

Answer 17

problem is feasibility on large scale
Barriers are social pressures to use and manage land in different ways

Question 18

Can flood mitigation stratergies be balanced out?

Answer 18

Less technocratic approach (experts implmented decoded plan) much more about using stakeholders and what they want for landscpe managment

Question 19

Is holistic flood managemnet purely hydrlogical?

Answer 19

No social conundrum