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by Matthew McCartney
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Water Resource Planning: integrating natural and built infrastructure
GTZ project
Matthew McCartney
Water infrastructure for development
Reservoir Storage per Capita (m3/cap), 2003
1,104 1,277
5,961
38
687
2,486
3,386
4,717
-
1,000
2,000
3,000
4,000
5,000
6,000
7,000
Water infrastructure is a cornerstone of development and of water security
Water resource projects provide the basis for regional development with “significant direct and indirect benefits for poor people” (World Bank, 2004).
Least developed countries are the most poorly served
Climate change adds further urgency to investing in water infrastructure
However…
43687 1,104 1,277
2,4863,386
4,7175,961
14,275
0
2000
4000
6000
8000
10000
12000
14000
16000
Eth
iopi
a
Sou
th A
fric
a
Me
xico
Tha
iland
Ch
ina
Bra
zil
Aus
tral
ia
No
rth
Am
eric
a
Gha
na
m3/c
apit
a
Not a simple relationship – some countries with greater infrastructure development have greater poverty
Water infrastructure is often highly contested
Significant debate about what sort of infrastructure is best for poverty alleviation
And worse….
y = -27.51ln(x) + 62.462R² = 0.9149
0
20
40
60
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100
120
0 1 2 3 4 5 6 7 8 9Ma
laria
case
s/100
0 pe
ople
Distance f rom the reservoir (km)
Dams, reservoirs, irrigation systems can undermine peoples’ livelihoods (i.e. create poverty)
Natural ecosystems provide services
• Livelihoods and wellbeing of many poor people are dependent on these services
• Construction of built infrastructure can damage or destroy ecosystem services by draining/flooding wetlands or disrupting seasonal patterns of river flow.
There are always trade-offs
OptimiseOverall Benefit
Impacts
•Livelihoods
•Health
•Biodiversity
Irrigated Agriculture
Domestic Water Supply Hydropower Industry
Floodplain products
Dam operation options
Fisheries Recession Agriculture
Floodplain Grazing
Legislation • local/national laws
• international obligations
Water availability • hydrological regime Engineering
• reservoir storage • outlet structures
Social/economic conditions
• livelihoods adaptation to dams
Development drive • political imperatives
Key
Objective
Variables
Decisions
Constraints
Desired ecosystem condition
• present/future condition
Provisioning services
Regulatory services
Cultural services
Supporting services
Natural basin
CropsHydropower
IndustrialRegulation of water balance
Erosion control
Climate regulationSoil
formation
Nutrient cycling
Recreation
CropsHydropower
IndustrialRegulation of water balance
Erosion control
Climate regulationSoil
formation
Nutrient cycling
Recreation
Intensively utilized basin
CropsHydropower
Industrial Regulation of water balance
Erosion control
Climate regulationSoil
formation
Nutrient cycling
Recreation
Multifunctional “green” basin
Striking a balance
The issue
How can ecosystem services from “natural infrastructure” be integrated into investment planning and decisions for “portfolios” of infrastructure development to improve water security outcomes for poor people and developing countries?
The reality
Water infrastructure development for poverty reduction = a social-ecological optimisation problem, complicated by unknowns, uncertainties, contested facts and complex systems.
Decisions are shaped as much or more by politics and political economy as scientific knowledge.
Potential Research
. • Methods to quantify and value ecosystem services
• Tools for guiding investment in “portfolios” of built and natural infrastructure (understanding of trade-offs etc.)
• Knowledge useful for decision making and building consensus within political-economic realities (for negotiating).
• Strategies for managing uncertainties and risk to increase resilience to climate change and variability
Quantifying regulating functions
Monthly flow upstream and downstream of the Luswishi floodplain
0
20
40
60
80
100
1-O
ct-8
0
1-No
v-80
1-De
c-80
1-Ja
n-81
1-Fe
b-81
1-M
ar-8
1
1-Ap
r-81
1-M
ay-8
1
1-Ju
n-81
1-Ju
l-81
1-Au
g-81
1-Se
p-81
Flow
(m3 s
-1)
Daily flow with and without floodplain
Without floodplain (simulated) With floodplain (observed)
Some ecosystems act like natural reservoirs and regulate flows: • decrease wet season flows • increase dry season flows
Method (based on reference FDC and spatial interpolation technique) enables generation of a flow series “without” the ecosystem
This enables quantifiable comparison of flow with and without the ecosystem.
Flow analyses
0
20
40
60
80
100
120
140
1 10 100
Peak
floo
d flo
w (
m3 s
-1)
Return period (yrs)
Flood Frequency
With floodplain (observed) Without floodplain (simulated)
Extrapolated
Impacts of Luswishi floodplain on floods
Return Period (yrs)
Flood magnitude (m3s-1)
With floodplain Without floodplain
2 47 73
10 65 105
25 71 115
50 75 122
100 79 128
200 82 133
BFI Mean annual minimum (m3s-1)1-day 10-day
With floodplain 0.994 2.96 3.04Without floodplain 0.886 2.02 2.13
Combining ecosystem services and water productivity concepts
Expanding the water productivity concept?
Natural Basin Increasingly modified Basin
Benefits from natural components
Benefits from modified basin components
Sum of benefits
Total productivity (i.e. overall benefits)
Quantifiable Non-quantifiableBenefits
Wat
er u
se
Dep
letin
g use
sN
on-d
eple
ting u
ses
Objectives
alternative infrastructure investment paradigm
water resources development incorporating the priorities of poor people…
sustainablewater securitygrowthreducing disaster riskclimate resilience
knowledge and tools for real-world decision making
how to “do development” without ruining things?
Thank you
• There are always trade-offs – some people benefit and some lose
• Divergence of values, needs and interests of different groups
• Biases and subjectivity in valuations and interpretations of “facts”
• Disagreements in which cultural, social, economic and ecological dimensions are intertwined
• Unequal power and influence of actors
Why decision-making about water infrastructure is difficult
Physical Storage Continuum
Aim: maximizing productivity/benefits
Natural Basin Increasingly modified Basin
Benefits from natural components
Benefits from modified basin components
Sum of benefits
Total productivity (i.e. overall benefits) All change needs to be
considered in relation ecosystem services and trade-offs
Range of physical storage options
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