Integration of Groundwater Management into Transboundary ... · Regional Training Workshop on...

Regional Training Workshop on Integrating Groundwater Management within River Basins, 15-18 January 2019, RCGW, KEWI, Nairobi, Kenya

Integration ofGroundwater Management

intoTransboundary Basin Organizations in

Africa


Integrated Water Resources Management IWRM

and Groundwater Management

Framework

Module 2


•Why Groundwater Management for River Basin Organizations? •Groundwater – the Resource•Groundwater Management Issues•IWRM in Groundwater Management •Transboundary Groundwater


Why Groundwater Management for River Basins?

• Groundwater and surface water interact in the hydrologic cycle and therefore need to be managed as a single water resource.

• There are vast volumes of groundwater in storage that can provide water managers with valuable new resources.

• Conjunctive management of groundwater and surface water can provide water managers with valuable tools and opportunities to optimize water use within river basins.


Groundwater in the Hydrologic Cycle


The rate of flow and hence the turn-over time for groundwater is orders of magnitude slower than for surface water and hence groundwater requires a

different management paradigm.


Conjunctive management of groundwater and surface water is a guiding principle of IWRM.

• Traditionally the integrated management of surface and groundwater has lagged behind in many RBOs for various reasons:

✓Institutional separation of groundwater and surface water management,

✓Different knowledge and skill systems required for surface and groundwater management

✓Aquifer systems do not always coincide with river basin boundaries.

➢Given the important role of RBOs in the African regional transboundary water management, RBOs have a unique opportunity to fully integrate groundwater and surface water management and thereby manage their catchment water supplies in an optimal and sustainable manner.


Importance of groundwater• Groundwater is the main source of water for domestic use for more than 2

billion people in the world.

• The accelerated global development over the past few decades has been significantly supported by groundwater.

• It is the major source of water for many mega cities (Mexico City, Dhaka, Dar esSalaam, etc.)

• Africa is blessed with abundant groundwater resources.

• Groundwater is under-developed in many parts of the African continent

• Additional and sustainable use of groundwater will be vital for the achievement of the ‘UN Sustainable Development Goals’ and for adaptation to climate change


Regional Distribution of Global Fresh Water Resources


Type of

storage

Natural/

Artificial

Installed

capacity

(km3)

Annual

Recharge

(km3/yr)

Used

capacity

(km3/yr)

Surface water

Natural

(rivers & lakes)

Artificial

(Large dams)

225,000

6.000

8,000 2,000

3,800

Ground water

Natural

(< 400 meters)

Artificial

(MAR)

3,500.000

20-50

300,0000 3.000

20-50

Sources: Gleick (2000) , IWMI (2000), IGRAC (2006)

Storage: surface water & groundwater


Groundwater•Positive points•Large volumes in storage – 97% of available freshwater.•Widely dispersed & available where needed: rural water supply. •Relative low cost compared to surface water- allows private development.•Potable without treatment•Drought resistant – no evaporation•Requires little land

•Negative points•Storage & conveyance only•Must be pumped •Limited flows•Mineralized•Difficult & expensive to assess•Need to involve users in management plans


Why is Groundwater Management needed?

• Management and protection of groundwater has been seriously neglected, potentially endangering the resource.

• The sustainability of groundwater is linked to policy issues influencing water and land use, and represents one of the major global challenges in natural resource management.

• There is a need to integrate groundwater and surface water management to ensure better overall water management and allocation.

1

1111


Interactions between surface water and groundwater


IssuesThe

hidden drought

300 m


IssuesThe groundwater

quality time-bomb


Opportunities: Staging of development:

Large capital outlayCapital costs spaced as demand rises


Opportunities: Decentralized user driven development. • Globally groundwater development has resulted in great social and economic

benefits, providing low-cost, drought-reliable high-quality water supplies – eg India.

• Because it is widely dispersed and relatively cheap to develop – it lends itself to development by individuals and households in most places.


Management Challenges


Some Consequences of GW abstraction

Excessive

pumping

When pumping is

further increased

Normal

consequences of

any groundwater

pumping


Historic data

Example: Water saving to reduce aquifer depletion

Monitoring data

Baseline data (reference)


GWM in Practice

• Identify critical points • Excessive drawdown with wells drying up

• Water quality deterioration such that it is unsuitable for original use

• Conflict between abstractors / users

• Uncontrolled waste dumping

• Decline of groundwater dependent ecosystems

• Reduced baseflow

• Declining springflow


IWRM Framework – based on Dublin Principles

❖ Three pillars❖ Economic Efficiency❖ Environmental

Sustainability❖ Social Equity

❖ 3 change areas❖ Management Instruments❖ Enabling Environment❖ Institutional Roles

22

Man

agem

ent I

nstrum

ents

Ecosystem Sustainability

Social Equity Economic Efficiency

Man

agem

ent I

nstrum

ents

Institutional Roles

Policy Legislation Regulation

Aquifer & River Basin Central-Local Public-private

Assessment Information

Allocation tools

Enabling Environment

Financing & Incentive Structure


Groundwater Management

Human BenefitsEconomic Benefits Environmental Benefits

Aquifer Storage

(groundwater resource)

SUSTAINABLE GROUNDWATER DEVELOPMENT

Artificial Recharge

(irrigation losses,

wastewater returns)

Natural Recharge

(excess rainfall, surface

water seepage)

Indirect Recharge

(aquitard leakage,

cross-formational flow)

Water for development

Groundwater abstraction

(agriculture & Industry)

Water for the Environment

Groundwater discharge

(Springs, surface water,

wetlands, coastal zone)

Water for People

Groundwater supply

(drinking water & Sanitation

and livelihood)

His

cock

, 20

02

THE RESOURCE

THE USES

THE CHALLENGE


ACTION PLAN

MANAGEMENT INSTRUMENTS AND MEASURES

RESOURCE SETTING

HYDROGEOLOGIC CONDITIONS definition of manageable groundwater bodies

resource renewability, recharge rates and sw interactions

aquifer storage characteristics and economic reserves

susceptibility to irreversible aquifer/ecosystem degradation

SOCIOECONOMIC SITUATION

analysis of groundwater use drivers (urban vs rural)

(waterwell construction costs, macro-policy interactions

such as energy subsidies and crop price guarantees)

groundwater use and users profile

REGULATORY PROVISIONS zoning and source protection

groundwater use regulation

POLICY ADJUSTMENTS

macro-policy interventions

linkage with planning

IMPLEMENTATION OF MANAGEMENT MEASURES investment priorities and scheduling of actions

mobilizing stakeholder engagement and essential roles of government

USER PARTICIPATION knowledge and awareness

strengthening user organization

local regulation

DEMAND-SIDE MEASURES

substitution of uses (crops, agronomy)

efficiency measures/ saving

water charging

SUPPLY-SIDE MEASURES

natural/ artificial recharge

retention

alternative sourcing

conjunctive management

QUALITY MEASURES

prevention

adaptation

water treatment

remediation


Most widely-occurring aquifers


no management = no maintenance = no water


Some Groundwater Management Tools.

Maps: - groundwater managers are finding that thematic (semi)-quantitative maps provide significant spatially valuable data. B

Databases: - databases are essential in order to monitor the location of groundwater resources development and the changes that are taking place to the resource.

Monitoring networks: - these are the fundamental management instrument to gather information about what is happening to the hidden groundwater resource and should monitor both the resource quantity and resource quality.

Modeling: - models can provide detailed information for groundwater management and planning and are useful especially for heavily used aquifers.

Analyses: - analyses of the data and reporting results are an essential part of the management framework.


Villholth et al. 2013.


Villholth et al. 2013.







Key Conclusions

• Groundwater represents a major portion of fresh water resources

• Hydrogeologic and socio-economic conditions location-specific

• Surface water and groundwater should be managed as one resource.

• Involve the main stakeholders in the resource management and development

• Need for capacity building both among water resource authorities and water users to implement management measures


When the well is dry, then the value of water is understoodMark Twain


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