natural flood management ( pdf 5.4 mb)
TRANSCRIPT
A natural engineering approach to water management
Paul Quinn and many others…
School of Civil Engineering and Geosciences
NERC Knowledge Exchange Fellowship at ARUP
http://research.ncl.ac.uk/proactive/
The problem
• More flooding
• More pollution
• More drought
• Less biodiversity
• Carbon loss
livestockgrass
arable
arable
(winter crop)
grass
(silage)
Tarland: 183218672011
Farmed soil: increased runoff and unchecked runoff
Lower infiltration + lower soil water storage= lower infiltration capacity
Belford, Northumberland
6
The 5% Future
http://research.ncl.ac.uk/proactive/5future/
Eroding landscapes and gravels
Netherton Flood schemeThree-tier RAF sediment trap
• Water storage capacity ≈ 280 m3
• 70 ha contributing area
During a flood
0
2
15
min
ra
in (
mm
)
0.0
5.0
10.0
Flu
me
stag
e (c
m)
0
0.2
0.4
TP c
on
c. (
mg
l-1)
TP in TP out
0
100
200
300
SS c
on
c. (
mg
l-1)
SS in SS out
0
2
4
6
8
NO
3co
nc.
(m
g l-1
)
NO3 in NO3 out
Retention (% concentration)
• SS: 25 – 67 (49% net retention)
• TP: 16 – 44 (33% net retention)
• NO3: 5 – 85 (18% net retention)
~ £2000 of work
Performance – Three-tier sediment trap
DykeheadNational Trust
11
Saplings, Sponges, Sandbags and Sympathy
‘Sandbags and Sympathy are Not Enough’ Belford 2008
Trees are not enough
‘Make the land work more effectively as a sponge by
restoring water retaining habitats over large areas.’Wildlife Trust Sponges are not enough
NFM might be enough for Belford but it is not enough for big catchments
Lustrum Beck (proposed) – 60,000 m3 in 1 km2
We need toscale up!
Blue-Green Citiesatchment area (1.8km2)
Leazes Moor
Leazes Moor Proposal
What Next?
• What do we need to do
- Storm Desmond?
• New research – Catchment Pilots?
• Engineering a new landscape for the future?
• Farm payments – a new deal for farmers?
BBC News http://www.bbc.co.uk/news/uk-politics-35298707
BBC News http://www.bbc.co.uk/news/uk-35246752