Transcript 8. Wessex Water - Innovative responses

Catchment Management: Impact of climate change on
delivery and investment
Innovative responses to Climate Change
Luke de Vial
Head of Environment and Water Resources
21 November 2014
2
•
Impacts of climate change
•
Link between catchment management and climate
change
• Programme going forward (AMP6)
3
Climate change risks
2050s rainfall
Summer
Unlikely
Most likely
Unlikely
Low emissions
Medium emissions High emissions
-30% to -40%
-40% to -50%
-40% to -50%
-10% to -20%
-10% to -20%
-20% to -30%
+10% to +20%
0% to +10%
0% to +10%
0% to +10%
0% to +10%
0% to +10%
+10% to +20%
+10% to +20%
+10% to +20%
+20% to +30%
+20% to +30%
+30% to +40%
Winter
Unlikely
Most likely
Unlikely
4
March to February total rainfall
2012-13: 1238mm
1300
1200
1100
1000
900
800
700
600
2011-12: 635mm
500
2011-12
2006-07
2001-02
1996-97
1991-92
1986-87
1981-82
1976-77
1971-72
1966-67
1961-62
1956-57
1951-52
1946-47
1941-42
1936-37
1931-32
5
Rainfall, April 2011 – Dec 2011
Compared with 1961-90 average
Apr’11
Jan’12
Dec’12
HIGHEST SCORING RISKS
Warmer Reduced water quality (discolouration, odour)
temps Increased odour from sewage works & sludge
Less flow in sewers: silting up, blockages, spills
from overflows
Drought
Less flow in sewage works: odour problems
Less flow in rivers: lower dilution of effluent
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HIGHEST SCORING RISKS
• Sedimentation in water sources: reduced
raw water quality
More
intense / • Assets flooded: service failure; need to
prolonged
reinforce flood defences
rainfall
• Sewers overwhelmed: spills, properties
flooded
8
One issue that is low risk
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Adaptation measures
• Protecting critical assets from flooding
• More interconnectivity of supplies
• Increasing capacity of pipes, treatment works
• Surface water management
10
Asset flood resilience – protecting critical
assets (water)
Improvements following
flood risk
assessments at Friar
Waddon & Lake
1 in 100 year flood
Includes climate change
allowance
•
Security and Emergency Measures Direction
– Further security protection measures to comply with national
security standards
11
Asset flood resilience – protecting critical
assets (wastewater)
•
Pumping station in Westonsuper-Mare
•
Flood damage to the installation
could lead to flooding in parts of
the town
•
Raising motor & electrical
controls previously located below
ground and flood level.
12
Climate change and catchment
management link?
•
Climate change may cause issues that catchment
management can address
•
Catchment management approaches are generally low
carbon
•
Catchment management the right solution to problem –
climate change or not!
13
Climate change causes catchment
problems
14
Eagle Lodge
12
Nitrate Concentration (mg/l N)
11
10
9
8
7
6
Drinking Water Standard
Measured
Modelled Long Term Trend (LTT)
LTT + Woodyates WL Fn
LTT + Black House WL Fn
5
4
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
15
16
17
Catchment management is low carbon
18
Greenhouse gas emissions: historical and
future scenarios (ktCO2e)
19
Some issues inherently catchment
20
11
10
9
Nitrate (mgN/l)
8
7
River Frome
6
5
Wessex Water Eagle
Lodge Source
Poly. (Wessex Water
Eagle Lodge Source)
Poly. (River Frome)
4
3
2
1
1965 1967 1969 1971 1973 1975 1977 1979 1981 1983 1985 1987 1989 1991 1993 1995 1997 1999 2001 2003 2005 2007 2009 2011
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Engineering-led, trad. capex
Catchment
management
Many
agencies +
public
Demand
management
Water grid & trading,
bigger sewers, storm
tanks, relocated
assets, flood
protection, energy selfsufficiency
Sustainable
Leakage work
drainage
Watercourse
management
Few
agencies
More localised / ‘softer’
22
Engineering-led, trad. capex
Catchment
management
Many
agencies +
public
Demand
management
Water grid & trading,
bigger sewers, storm
tanks, relocated
assets, flood
protection, energy selfsufficiency
Sustainable
Leakage work
drainage
Watercourse
management
Few
agencies
More localised / ‘softer’
23
Greenhouse gas emissions: historical and
future scenarios (ktCO2e)
24
Summary of catchment work
Now
From 2015
Nitrate
12
15
(+6, -3)
Pesticides
2
4
Nitrate (river)
0
1 (big one)
Staff
5.5
16??
25
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