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

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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

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0 1 2 3 4 5 6 7 8 9Ma

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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

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1-No

v-80

1-De

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1-Ja

n-81

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b-81

1-M

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1-Ap

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1-Ju

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1-Ju

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1-Au

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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

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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