urban drainage

Question 1

urban hydrology

Answer 1

impermeable
runogg

sloped roofs, drains
storm sewer system
fill streams rapidly

less evapotranspiration
more runoff
less infiltration
imported water

less groundwater
less soil starage
base level flows reduced

flashy with low base flow

Question 2

issues to do with river flow

Answer 2

inc flow
inc flood
inc erosion
sediment in poor space

dec flow in dry weather
harm aquatic life

Question 3

issues to do with pollution

Answer 3

harm fish
poor water quality
recreational areas unsafe

Question 4

what is SUD

Answer 4

use natural processes in landscape to reduce flooding

use of swales, permeable surface etc

Question 5

soakaway

Answer 5

large vol store underground
can be put in gardens

5m from structures
no biodiverse gains
need sediment trap

Question 6

permeable paving

Answer 6

incorporate in concreted areas so not use extra land
1st level water treatment (good if lots traffic)

can clogg
councils may not adopt

Question 7

swales

Answer 7

landscaped areas provide amenity
biodiversity
naturally filter pollutants
simple maintain

impermeable soil need perforated pipe to collect water to move to next stage
need space
small vol storage
need landscaping

Question 8

ponds

Answer 8

biodiversity
large vol store
algae and plants filter pollutants
simple maintain

has to go through water polishing mechs before so quality not compromised