Wetlands and Poverty Reduction Project

Anglophone regional practitioners training course

MODULE 1

WETLANDS AND INTEGRATED WATER RESOURCE MANAGEMENT

By Dalmas O. Oyugi, Lucy Iyango

5 MAY 2007A Wetlands International project supported by DGIS

Lecture 2 IWRM

Learning Objectives

Understand:

Concepts of Integrated

Water Resources

Management

Role of wetlands in the

hydraological cycle,

and the link to

catchments/ basins

Key components of an

integrated ecosystem

approach in water

resources and wetlands

management

Why IWRM

Global withdrawals of

freshwater by people for

domestic, agricultural

and industrial purposes

have grown 35-fold in

the past century,

A further increase of 30-

35 % by 2025 will result

in severe water stress

for up to 1,100 million

people,

Freshwater is thus a

scarce resource.

Why IWRM

• Urban per capita water consumption in the industrialized

countries of Europe and North America ranges from 300

to 600 lday-1

• The per capita consumption in the developing countries

of Africa, Asia and Latin America is only 50-100 lday-1

• And in regions with insufficient water resources can be

as low as 10-40 lday-1

World water withdrawals by region (Original source: Shiklomanov 2006).

Water Use Vs Water Consumption

• Consumptive use is the process by which water is no

longer available for further use,

• Non-consumptive uses of water do not affect the

availability of that water for other users,

• Fishing and navigation for instance are examples of

non-consumptive water use,

Water Use Vs Water Consumption

• Water use is greater than the amount consumed

because of conveyance and other inefficiencies,

• E.g., return flows from agriculture are 20-40%,

• Water is used by agriculture, industry, municipal/urban

and reservoirs

• On a global scale, agriculture is the largest water user

with 66% of total water withdrawal and 85% of

consumption

Water Use

Within the hydrological cycle, there is a distinction of blue water and green water

On a global scale, about 40% of all rainfall becomes surface and sub-surface runoff,

This is what we call 'blue water'.

The rest of the rainfall either returns to the atmosphere directly as evaporation, or is taken up by the vegetation

This is referred to as 'green water'.

About 60% of the world food production is by green waterand 40% by blue water.

Introduction to concepts

Water Use...

• Environmental flows/"environmental water allocation".

– They are quality, quantity and distribution of water required

to maintain the components, functions and processes of

aquatic ecosystems

– Environmental water allocation deals with finding a balance

between sustainable use of water, protection of the water

resources & conserving the integrity of the wetland

ecosystems

Functions & Services of Wetlands

• A wetland function is the capacity of the wetland to provide

goods and services

• Services are the benefits that humans derive from the

functions of wetlands

• Functions are related strongly and directly to the

components and processes of the wetland,

• Services are based on the functions but depend more on

the use of these functions by humans.

Functions & Services of Wetlands

A number of functions performed by wetlands are:

– Hydrological/hydraulic functions,

– Climatic functions,

– Biodiversity functions,

– Habitat functions,

– Water quality functions.

Functions & Services of Wetlands

Hydrological Functions

• Wetlands cover about 6% of the earth surface

• Among the hydrological functions of wetlands are:

– Flood control, coastal erosion protection, sediment

retention, groundwater recharge/discharge, water holding

capacity, and the maintenance of stream and river flow,

Wetlands increase evaporation & decrease average river

flow, especially during dry periods.

Functions & Services of Wetlands

Climate Functions of Wetlands

• Wetlands play a role in reducing global warming

amelioration by carbon fixation

• The role of wetlands in the hydrological cycle (role in

evapotranspiration); and micro-climate stabilisation.

• Wetlands can store considerable amounts of CO2 in their

vegetation and sediments.

Functions & Services of Wetlands

Wetlands & Water Quality

• Filtration of particulates, nutrient stripping, biodegradation

of toxic compounds, heavy metal stripping and

accumulation and wastewater treatment.

Functions & Services of Wetlands

Habitat Functions of Wetlands

• Include the provision of wildlife habitats (fish feeding and

breeding grounds, bird feeding and breeding grounds)

terrestrial / aquatic habitats, and the protection of

biodiversity and gene pools

Functions & Services of Wetlands

Wetlands and Bidioversity

• The biodiversity function of wetlands comprises:

– Species and population diversity,

– The link between terrestrial and aquatic ecosystems,

– Microbiological activity,

– Maintenance of a large genetic pool, and wetlands as

connectors.

Functions & Services of Wetlands

Wetlands and Biodiversity cont’d

• Wetlands serve as connectors in several ways:

– They play a role in flyways and bio-geographical

islands

– They are a part of river corridors (upstream-

downstream connectivity),

– They provide longitudinal connectivity with estuarine

and marine environments

– They are ecotones (dry-wet connectivity).

Functions & Services of Wetlands

Wetlands and Biodiversity cont’d

• Wetlands also provide connectivity with global systems

in the form of carbon, nitrogen and water cycles.

• They also provide connectivity with the groundwater

(above ground-belowground connectivity).

The Dublin Principles and IWRM

• In 1992 in Dublin, the International Conference on Water and the Environment took place,

• The below resolutions were adopted by 114 countries as The Dublin Principles:

1. Water is a finite and vulnerable resource, essential to sustain life, development and the environment and should be managed in an integrated way

2. Water development and management should be based on a participatory approach, involving users, planners and policy makers at all levels

3. Women play a central part in the provision, management and safeguarding of water

4. Water has an economic value in all its competing uses, and should be registered as an economic good.

IWRM

• Dublin Principles are the pillars of integrated water

resources management,

• IWRM is the management of surface and sub-surface

water in qualitative, quantitative and environmental

sense from a multi-disciplinary and participatory

perspective and focused on the needs and requirements

of the society at large with regard to water for now and in

the future

• River basin approach is a perfect concept of IWRM

Social and economic

development

River basin ecosystem

Trigger for action

Triggerfor action

Water supply

Water demand

River basin water

resources

Water users Demand oriented

measures

Supply oriented

measures

Social and economic

development

Social and economic

development

River basin ecosystemRiver basin ecosystem

Trigger for action

Triggerfor action

Water supply

Water demand

River basin water

resources

Water usersWater supply

Water demand

River basin water

resources

Water users Demand oriented

measures

Supply oriented

measures

IWRM

• The traditional sectoral approach in management of water

resources was an inefficient "top-down"

• IWRM is holistic and takes into account all stakeholders ,

• Considers the temporal, spatial dimensions and the

institutional and legal framework,

• A key element of IWRM is that river basins are the

appropriate scale level for water resources management

IWRM covers resources like

• Surface water (rivers, lakes, wetlands, springs, pans, sea,

delta, coastal zones, mangroves, etc.)

• Groundwater (saturated zone, fossil water)

• Green water (percolating, capillary rising)

• Atmospheric water

• Wastewater (grey, black).

• IWRM considers all the natural aspects of water and also

considers the linkages between the various aspects

Nature of IWRM

• Puts water management in a broader context of socio-

economic development policy and environmental

management;

• Takes full account of all the sector interests related to the

functions and values of the water system, in a

participatory process with the stakeholders;

Nature of IWRM

• Considers the spatial and temporal variation of resources

and demands;

• Considers the full spectrum of relevant policy objectives

and constraints;

• Takes into account the different institutional levels

involved in water resources management.

snowpack

water tableinfiltration

streamflow

snowmeltand surface

runoff

precipitation

wetland storage

evaporationand transpiration

transpiration

streamflow

evaporation

ocean

groundwater movement tostreams, lakes, wetlands and the ocean

condensation

snowpack

water tableinfiltration

streamflow

snowmeltand surface

runoff

precipitation

wetland storage

evaporationand transpiration

transpiration

streamflow

evaporation

ocean

groundwater movement tostreams, lakes, wetlands and the ocean

condensation

Water movement

Conclusions

THANK YOU ALL