CUE - Urban Drainage

Question 1

hydrology of urban areas

Answer 1

lower evapotranspiration, high runoff, lower infiltration

Question 2

more or less precipitation in urban areas?

Answer 2

more

Question 3

ways in which urban areas move water quickly

Answer 3

sloping roofs
guttering (smooth and rounded)
camber of the road

Question 4

storage areas in urban areas

Answer 4

reservoirs
swimming pools
rivers
ponds/lakes (parks)
puddles

Question 5

urban storm hydrograph - lag time

Answer 5

lag time is short and surface runoff gets to the river quickly through the drainage system

Question 6

urban storm hydrograph - rising limb

Answer 6

steep rising limb as surface runoff gets into the river quickly through drainage system

Question 7

urban storm hydrograph - base flow

Answer 7

low base flow as low levels of ground/soil water due to impermeable surfaces

Question 8

ways to increase the storage capacity of urban rivers

Answer 8

dredging

channelisation

Question 9

what is hard engineering?

Answer 9

uses man made structures to prevent or control natural river processes from taking place.

Question 10

what is soft engineering?

Answer 10

works alongside the natural processes to manage the risk

Question 11

characteristics off hard management strategies (5)

Answer 11

require a lots of planning
expensive
changes or damages the environment
unsustainable
initial cost may save money in the long term

Question 12

characteristics of soft management strategies (5)

Answer 12

doesn't change to damage the environment
cheaper
sustainable
less intrusive
can take a long time to be effective

Question 13

hard engineering strategies is catchment management

Answer 13

diversion spillways
river straightening
river channelisation
natural levees and embankments

Question 14

soft engineering strategies in catchment management

Answer 14

afforestation
riverbank conservation
river restoration
floodplain zoning

Question 15

what does river straightening do?

Answer 15

they cut through meanders to create a straight channel, increasing the gradient and speed of flow, however may increase flood risk further downstream

Question 16

describe diversion spillways

Answer 16

permanent feature, by passing the main channel, for emergency use

Question 17

what is river channelisation?

Answer 17

lining straightened channels with concrete, reducing friction

Question 18

what can be done to natural levees?

Answer 18

they can be made higher, increasing capacity

Question 19

what are embankments?

Answer 19

raised riverbanks using concrete walls, blocks of stone or material dredged from the river bed
more sustainable option, looks more natural than concrete walling, more common in urban areas

Question 20

what does afforestation do?

Answer 20

evapotranspiration dissipates water that would end up in the river channel

Question 21

what does riverbank conservation do?

Answer 21

planting bushes and trees reduces lateral erosion, bank collapse and so silting up of the channel

Question 22

what is river restoration?

Answer 22

return of the channel to its natural course and so the reversal o artificial drainage management ‘solutions’ in the past

Question 23

what does floodplain zoning do?

Answer 23

restricts different land uses to certain locations

Question 24

social benefits of lamb drove

Answer 24

improvement in quality of life

increases amenity and social value to residents and local community

Question 25

economic costs of lamb drove

Answer 25

costs to build

Question 26

economic benefits of lamb drove

Answer 26

construction and ongoing maintenance costs have been 10% les than conventional pipe systems affordable houses external funding

Question 27

environmental costs of lamb drove

Answer 27

some people consider standing water to be a hazard (it isn't)

Question 28

environmental benefits of lamb drove

Answer 28

improvement in biodiversity and ecology improved water quality (lower heavy metal concentrations) reduces flooding more attractive

Question 29

location of lamb drove

Answer 29

Cambourne, west of Cambridge in Cambridgeshire

Question 30

what is lamb drove?

Answer 30

a 35 affordable homes development

Question 31

aims of lamb drove

Answer 31

to showcase practical and innovative sustainable water management techniques within new residential developments to demonstrate that suds are a viable and attractive alternative to more traditional forms of drainage and to deliver practical solutions for new housing areas.

Question 32

suds components in lamb drove

Answer 32

``` water butts permeable paving green sedum roof Swales detention basins and wetlands retention pond ```

Question 33

what do water butts do?

Answer 33

collect roof water for garden irrigation

Question 34

what does permeable paving do?

Answer 34

allows water to enter porous storage zones, and filter out pollutants

Question 35

what does a green sedum roof do?

Answer 35

reduces and treats runoff

Question 36

what do Swales do?

Answer 36

shallow open channels collect all excess water form the site, slowing the flow and continuing the treatment process.

Question 37

what do detention basins and wetland do?

Answer 37

slow down runoff rage and store water on a temporary short-term basis during floods

Question 38

what are retention ponds in lamb drove?

Answer 38

final storage of water before being released to a drainage ditch beyond the development site.

Question 39

name of the river restoration case study

Answer 39

Cheonggyecheon river project

Question 40

location of the Cheonggyecheon river

Answer 40

Seoul, South Korea

Question 41

what was the water course of Cheonggyecheon originally like?

Answer 41

a small seasonal stream

Question 42

why was Cheonggyecheon originally covered in?

Answer 42

it was seen as a sanitation and flood risk

Question 43

2 aims of the Cheonggyecheon river project

Answer 43

improved connectivity between the north and south sides of the city to create ecological and recreational opportunities in the centre of Seoul.

Question 44

3 features of work done to restore Cheonggyecheon

Answer 44

the elevated freeway and concrete deck covering the stream were dismantled. 22 bridges built to improve movement from north to south. water from the Hanang River is pumped in to create a consistent flow, which is treated to make sure it isn't polluted

Question 45

what did local businesses think about the Cheonggyecheon river project?

Answer 45

they originally saw it as an interruption or threat to their livelihoods

Question 46

how many people now visit Cheonggyecheon?

Answer 46

millions (18.1 million by the end of 2008)

Question 47

a piece of evidence to show that the Cheonggyecheon river project can be considered to be economically sustainable

Answer 47

since the restoration, development capital has been invested in residential construction and property prices have risen at double the rates elsewhere in the city

Question 48

how has the Cheonggyecheon river project affected temperatures

Answer 48

2.5 C reduction in average temperatures in the area

Question 49

why could the Cheonggyecheon river project be considered to be socially unsustainable

Answer 49

irregular surfaces are uncomfortable for people in wheelchairs and poorly lit, congested tunnels can be difficult for those with visual impairments and mobility issues

Question 50

what problems might planners face in the UK if they shed to carry out a scheme such as Cheonggyecheon on a major British city

Answer 50

lengthy project expensive - would need a lot of funding would require planning permission and a lot of resources invested stronger opposition from business and residents traffic issues involving needing to reroute and careful consideration of existing routes