- Introduction to groundwater resources management - 1 Introduction to groundwater resources...

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- Introduction to groundwater resources management -

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Introduction to groundwaterresources management

Jac A.M. van der Gun

, Previously employed with

Deltares/TNO Netherlands Geological Survey & International Groundwater Resources Assessment Centre

(IGRAC)

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Prologue:

Watershed and River Basin Management:How does groundwater fit?

Some distinguishing features of groundwater:1 Spatial units:

– aquifers rather than river basins

– other horizontal and vertical boundaries

2 Time scales of processes are different

3 Different storage/flux ratio

4 Less open to observation

5 Different interaction with people

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Introduction to groundwaterresources management

1 Introduction

2 Basic concepts and supporting subjects (shortened)

3 Water resources plan development (shortened)

4 Groundwater resources management issues

5 Implementing groundwater resources management

6 Case studies

Jac A.M. van der Gun

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Chapter 1: Introduction

• Role of water in human society (and beyond)• Complicating factors regarding water resources• Water resources management

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Water and Man– Domestic use– Irrigation– Production/cooling water– Navigation– Fishery– Source of energy– Recreation– Sewage/ wastewater disposal– Flooding/ water-logging– Environment and ecosystems

Water is …...a biological need, …..an economic commodity, ….and an environmental factor

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Role of groundwater

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Groundwater abstractionIntensity (mm/year)

Purpose of use

(shares of main water use sectors)

70% of global abstraction is by

ten countries only

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Groundwater abstraction

Evolution 1950-2010(in km3/yr)

Strong declines of the groundwater levels

Ogalalla, USA

Jeffara,Libya

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Competitive demands in a water scarcity environment

reservoir

town

projectedcomplex ofirrigated lands

projected reservoir

river system

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Interdependency

Project 1 goal 1Project 2 goal 2

Project n goal n

Traditional perception

A more realistic perception

Project 1 outcome 1Project 2 outcome 2

Project n outcome n

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Soil salinization in ancient Mesopatamia

• Prosperous irrigation areas• Steadily progressing soil salinization• Reactions:

- moving to new lands - fallow-land rotation - from wheat to barley

• Results:- general decline- diminishing crop yields- abandoned agricultural lands

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Mechanism of soil salinationVolumes of water: R I ET

rainfall irrigation evapotransp.

Salt concentrations: cr ci ce

Control volume of soil: (undrained)

cc

capillary flow C

Soil salt quantity S

Mean annual soil water balance: R + I + C - ET = 0

Mean annual soil salt balance: Rcr + Ici +C cc - ETce = ΔS

Because ce < cr , ci,,, cc it follows: ΔS > 0

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It took long before the hydrological cycle was correctly understood

Oceanus theory

Condensationtheory

Percolationtheory

HomerosThales of MiletePlinius the ElderLeonardo da VinciJohann Kepler

AristotleSenecaRené Descartes

Theories on the origin of groundwater and springs

VitruviusBernard PalissyPierre PerraultEdmund HalleyEdmé Mariotte

Athanasius Kircher, 1665

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Global population growth1900 - 2000

0

1000

2000

3000

4000

5000

6000

7000

1900 1920 1940 1960 1980 2000

millio

ns

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Changing water demands per capita

• Increasing wealth:- affordability of buying water- willingness to pay for water

• Motivators for more water per capita: - improvement of hygiene and health- improved & controlled food production

- steadily developing water using industry- comfort, recreation and leasure

• Enabling technological development:- knowledge on water resources- water development technology- water use technical infrastructure

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Evolution in groundwater resources development technology

shaduf

Noria (saqiyah)

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Climate change

Source:IPCC, 2001

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Complicating factors regarding water resources

- Conflicts of interest - Interdependency of activities - Poor perception of reality / lack of data- Water is a common property resource- Water is a vulnerable resource- The world is continuously changing (local & global change)

Consequently……there is often a need for intervention

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Water resources management: intervention objectives

Conserve and control water resources + related ecosystems and environment

Provide water and maintain water functions according to requirements

Maximize total benefits from the resource and allocate them optimally

Minimize costs involved in water sector

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Typical evolution in water sector activities

Time

reconnaissance

water resources development

water resources management

increasing populationindustrialisationhigher consumption levelsawareness of interdependencies

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Groundwater resources management (GWRM) defined:

“A planned and ongoing activity to optimize the exploitation and use of regional or national groundwater resources……...

……. taking into account the sustainability of the groundwater resources and the groundwater related environment and ecosystems.”

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Groundwater resources management in a nutshell

Groundwater

Problems?Opportunities?

Planning

Plan approval and acceptance

Implementation

Monitoring

Other policy fields

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Chapter 2: Basic concepts and supporting subjects

• Systems approach• Groundwater systems• Water demands• Economics

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Systems approach

“real world”

water resourcessystem

“systems”and

interrelations

system 1

system n

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System operation (1)

Natureof

system

Physical laws

Systemoperation

System

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System operation (2)

Systemoperation

System

Input Output

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System operation (3)

Natureof

system

Physical laws

Systemoperation

System

Input Output

System

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The hydrological cycleas a system

land surface

atmosphere

surface water

oceans

soil

groundwater

deep lithosphere

vegetation

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Systems approach to water resources management

Socio-economic system

Present state,functions,performance, etc.

Desired state,functions,performance, etc.

Physical water system

State at time t Systemoperation

State at timet + Δt

Decisionvariables

Uncontrollablevariables

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Some aspectsof groundwater systems

• Invisible resource• Ratio storage/flux is large

(mean residence times between 10 and 1,000 yrs are common)

• Common pool & open access resource • Many functions• Schematization

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Functions of groundwater systems

More than a source of water only …..

• “sustained yield” reservoir• “mining” reservoir• reservoir for artificial recharge

• conduit for water transmission• energy absorber (pumping)• source of energy (geothermal energy)• reservoir for seasonal heat storage

• water quality modifyer• control of base flow and springs• water supply to

phreatophytes/wetlands• control of land subsidence

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Groundwater in a “lumped system” schematization

Groundwater system(stored volume, water quality, average head, etc.)

Subsurfaceinflow

Direct recharge

Recharge fromstreams, lakes, etc.

Artificial recharge Abstraction

Spring flow & discharge to streams, lakes, etc.

Diffuse discharge

Subsurfaceoutflow

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Distributed groundwater systems(1) hydraulic schematization

(2) flow systems schematization

aquifer

Aquitard/aquiclude

aquitard

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Water demands

Quantity:• Domestic: total and per capita demands• Irrigation: irrigation requirements, leaching requirements• Industry: process water, cooling water demands• Environment /nature: desired/ minimum/ maximum groundwater level

Quality:• Standards for drinking water quality• Idem for irrigation, industry, environment, nature• Aspects: chemical, bacteriological, physical (incl. sediments)

It is important to know what impacts violating any of the requirements or standards will have

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Role of economics in water resources management

• Comparing economic merits (scores) of alternatives or strategies

• Defining economic optima: Maxx Profit = (ΣR-ΣC)

• Understanding or predicting people’s behaviour

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Conventional economic theory ignores market failures

• Missing markets• Poorly defined ownership or user rights• External benefits • External costs (disbenefits)• Unequitable allocation of benefits/costs • Lack of intergenerational equity• Environmental and sustainability problems

Market failures are triggers for government interventions

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Natural resources

• Characterised by “stock” (reserves) and “flow” (quantities transfered per unit of time)

• Important distinction:

- perennial resources

- renewable resources

- exhaustible or mining resources

Examples:

solar energy

water, fish, forests, etc

oil and gas, mineral ores

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Optimal exploitation of natural resources

Dilemma:Exploit ‘stock’ - or exploit ‘flow’ - or both?

Different views, criteria and priorities:e.g.: • Presence/absence of substituting resources• Economic optimization• Sustainable development• Poverty alleviation• Protection of ecosystems• Self-supporting food production

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Economically optimal exploitation of natural resources

Dilemma:Exploit ‘stock’ - or exploit ‘flow’ - or both?

Economic optimization:Given : S = stock of natural resource

b = input of natural resource a = input of other production factors G = growth function of natural resource V = value of discounted profits

π = profit function

Then the optimum follows from:

subject to:

dteb).π(a,=VMAX rt-T

o=t

b)(a, b-G(S)=

dt

dS

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Set of equations for natural resources management

(1) “Maximum Principle”

(2) Portfolio balance equation

(3) Dynamic constraint

dteb).π(x,=VMAX rt-T

o=t

(x)

dteb).π(x,=VMAX rt-T

o=t

(b)

b-G(S)=dt

dS

Note:x is envisaged production output

Production output oriented

Resources use oriented

Continuity equation

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Introduction to groundwaterresources management

1 Introduction

2 Basic concepts and supporting subjects

3 Water resources plan development

4 Groundwater resources management issues

5 Implementing groundwater resources management

6 Case studies

Jac A.M. van der Gun

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Chapter 3: Water resources policy and plan development

• Basic aspects

• Outline and elements of water resources management planning

• Models used for groundwater resources management planning

• ‘Open’ or ‘interactive’ plan development

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Difference between policies and plans

• A policy encompasses in general terms the objectives, priorities and the line of actions opted for

• A plan translates this policy into action, it facilitates communication on it among stake-holders and it enables the results to be monitored

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What is planning?

“Planning is the process that converts data and information into a decision”

O. Helweg, 1985

Planning is commonly a cyclic process: the plan

is intended to cover a limited period of time (planning period) and needs to be updated periodically

Before starting planning: consensus needed on jurisdiction, scope, stage (hierarchical level) and on the roles of partners in the planning process

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Hierarchical levels in water resources management

GENERAL POLICIES

AREA-SPECIFICSTRATEGICPLANNING

IMPLEMENTATION AND MONITORING

development scenariosobjectivesconstraintspreferences

area-specificWRM plan

generaldirectives

feed-back

feed-backfeed-back

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Potential main partners in planning

Target group

Decision makersTechnical specialists

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Framework for WRM planning

WATER RESOURCES ASSESSMENTWater resources, demands, scenario conditions, issues, etc.

STRATEGIC ANALYSISObjectives, options, strategies, measures, evaluation

VIABILITY ANALYSISFeasibility and expected acceptance

PLAN APPROVAL

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Water resources management objectives and criteria

(examples)

• Economic efficiency B-C, NPV

• Equity water allocation income from water

• Sustainability stock, water levels, water quality

• Safety no. of victims,damage

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Decision space and feasibility

Technical feasibility

Economic feasibility

Financial feasibility

Political feasibility

Legal feasibility

Environmental feasibility

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Main types of models in WRM planning

• Simulation models

• Optimization models

• Decision rules

• Evaluation models

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Simulation models

• Differential equation• Model parameters• Initial conditions• Boundary conditions• Solution algoritm

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Examples of differential equationsfor simulation models

t

hS=h)k( si

t

c=c)v(-c)D( ii

t

p=

z

p(p)c 2

2

v

Saturated groundwater flow

Solute transport

1-D consolidation

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Optimization models

Given: decision variables x1 through xn (control variables)

Then an optimization model typically consist of:

(1) OBJECTIVE FUNCTION

Maximize F(x1, x2 , ……….. , xn )

2) CONSTRAINTS

gi(x1, x2 , ……….. , xn ) < 0 or = 0 (j=1, 2, ….., m)

If all equations are linear linear programming

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Example: Set of equations for optimizing natural resources management

(1) “Maximum Principle”

(2) Portfolio balance equation

(3) Dynamic constraint

dteb).π(x,=VMAX rt-T

o=t

(x)

dteb).π(x,=VMAX rt-T

o=t

(b)

b-G(S)=dt

dS

Note:b = groundwater pumping ratex = envisaged production outputπ = profit functionG(S) = growth rate of resource

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• Used to compare strategies or alternatives

• Economic models:

Present Value of Discounted Cash Flows,

Internal Rate of Return, etc.

• Multi-Criteria Decision Models (MDCM)

Evaluation models

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Principle of multi-objective evaluation

Evaluation

Alternative 1 Alternative 2 Alternative 3 Alternative 4

Objective 1:Maximize PV

Alt. 4Alt. 2Alt. 3Alt. 1

Objective 2:Wetland

conservation

Alt. 2Alt. 3Alt. 1Alt. 4

Ranking:

Best

Worst

Multi-criteria decision methods

are needed to underpin a decision

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Dealing with uncertainty in planning

• Safety factors• Emergency provisions• Statistical analysis• Sensitivity analysis• Stochastic approaches• Risk analysis• Additional data collection

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‘Open’ or interactive plan development

• Top-down planning (technocratic or ‘closed’) often fails: no or limited acceptance/co-operation by stakeholders

• Common reasons: – lack of mutual understanding government-stakeholders – lack of trust between parties– lack of confidence in the quality of the plan– unsolved conflicts of interest– lack of commitment of essential partners

• Therefore trend towards interactive plan development, involving representation of all major stakeholders

• Degree of interactivity may vary

• Real communication is a must

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Arnstein’s sequence of interactivity

Informing

Inquiring

Consulting

Co-producing

Delegating

Selfruling

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Techniques in IP

• Brochures and leaflets• Press articles• Radio and TV programmes• Information meetings• Enquiries and interviews• Work shops• Public hearing meetings• Stakeholder comments and position statements• Working groups and task forces• Electronic meetings and discussion sessions• etc.

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Introduction to groundwaterresources management

1 Introduction

2 Basic concepts and supporting subjects

3 Water resources plan development

4 Groundwater resources management issues

5 Implementing groundwater resources management

6 Case studies

Jac A.M. van der Gun

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Chapter 4: Groundwater resources management issues

• Groundwater management policy and plans have to address the issues relevant for the area concerned

• World-wide experience is useful to help identify issues and to benefit from ideas and solutions already developed elsewhere

• Diagnostic analysis on relevant issues should take place in an early stage of plan development

• Main approaches to identify relevant issues:– inference from water system characteristics– communication with stakeholders

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Main groundwater resources management issues

Rate of aquifer exploitation Encouraging or restricting groundwater pumping?Allocation of scarce groundwaterConjunctive management

Salinity controlPollution controlConservation of ecologically desired ‘water type’

Groundwater level controlControl of land subsidence

Water quantity management:

Water quality management:

Environmental management:

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Groundwater development in the Sadah aquifer, Yemen

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Rate of aquifer exploitation Sadah aquifer

Wajid Sandstone

Granitic gneisses Schists

2000 m

0

Rainfall: 100 - 200 mm/yearIn 1983: 1160 wellsEstimated recharge: 7 - 10 M m3/yearNet pumping: 51 M m3/year

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Early diagnosis Sadah aquifer

• Water balance:

mean depletion of 42 M m3 / year

• Numerical model simulation:

in most likely scenario there will be continuous groundwater level decline of 4 - 5 m per year

• How to manage the aquifer?

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Rate of aquifer exploitation(groundwater storage management)

grw.storage

grw.level

time

(1) sustainable yield (2) mining, followed by sustainable yield (3) mining, followed by exhaustion

(1)

(2)

(3)

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Burt’s approximate decision rule

• Groundwater pumping (at rate Q) from isolated aquifer

• Short-term profits of over-exploitation are balanced against perpetual additional pumping cost (externality)

• Expanding abstraction beyond mean sustainable yield (MSY) is profitable until:

annual costsor revenues

MSY Qopt aggregate abstraction rate Q

revenues minus direct costs

adjusted profit

externality due tostorage depletion

S

S)NB(Q,

r

1=

Q

S)NB(Q,

slope = Q

NB

slope =S

Q

S

NB

r

1

pseudo optimum

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Profit function in Burt’s rule

EB+EC-EN-

Sqr-dt

dqS+

dt

dSq+

bc-aw-xp=π

eee

e

eee

Check whether these simplifications are acceptablefor the case considered for application

Production profit

Portfolio profit

Externalities

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100

grapes

MSYwheat

0 100 200 years

Optimal abstraction ratesSadah aquifer

according to Burt’s rule

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What happened actuallyin the Sadah area?

Gwl (m)

-30

-40

-50

-60

-70

-80 1983 1985 1987 1989 1991 1993 1995

• Abstraction doubled from 1983 to 1995• Many dry wells• Sharp increase of ground water cost• Loss of irrigation profitability• Small farmers gave up and migrated

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What about the following statement?

Groundwater storage depletion (ΔS) occurs only when groundwater abstraction (A) exceeds natural groundwater recharge (R)

….. and in that case it can be calculated as follows:

ΔS = A – R (all values expressed as volumes per unit of time)

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The previous statement is wrong:“The water budget myth” (Bredehoeft et al.)

• Groundwater balance should include changes in recharge (ΔR), natural discharge (Q) and changes in natural discharge (ΔQ): ΔS = Outflow – Inflow = A + (Q + ΔQ) – (R + ΔR)

• Typical components of ΔR: induced recharge, return flows and artificial recharge.

• Typical components of ΔQ: reduction in spring flows, evapo(transpi)ration and baseflows (then ΔQ is negative)

• Many hydrogeologists think according to the water budget myth, but their intuition is wrong

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Maximum sustainable yield

• Any new abstraction is intitially fed completely by storage depletion

• The storage depletion – in turn – may lead to reduction of natural groundwater outflow (ΔQ) and increase of recharge (ΔR)

• MSY depends on how the system will adapt at the long run: MSY = - ΔQmax,final + ΔRmax, final

• It follows for isolated aquifers without artificial recharge: MSY ≈ R

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Encouraging or restricting groundwater pumping?

• Water needs (quantity and water use category)• State of aquifer (over- or underexploitation)• Groundwater quality• Environmental effects of groundwater pumping• Presence/absence of alternative supplies• Profitability of water use• Renewable or non-renewable groundwater?

Depends on:

Partly conflicting aspects - thus: choice based upon preferences

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Renewable versus ‘non-renewable’ groundwater

Renewable groundwater:• Recharge is sufficient for realistic

sustainable development• Hence, the resource is exploited by

virtue of its renewal• Mean annual recharge typically

more than 0.1 % of storage• Abstraction leading to steady

reduction in groundwater storage is called ‘overexploitation’

• Part of abstraction exceeding maximum sustainable yield is called ‘overdraft’.

• Renewable grw is more common than non-renewable groundwater.

Non-renewable groundwater:• Recharge is insufficient for realistic

sustainable development • Hence, the resource is exploited by virtue

of significant storage • Mean annual recharge typically less than

0.1 % of storage• Abstraction leads to steady reduction in

groundwater storage and is called “mining”

• Non-renewable groundwater usually is fossil, but not all fossil groundwater is non-renewable

• Examples: N-African deep aquifers (NWSAS, Nubian Sandstones, etc.), Arabian Platform aquifers, Great Artesian basin.

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Environmental impacts of exploiting ‘non-renewable’ groundwater of the

NWSAS

Exploitable reserves: 1280 km3Current abstraction rate: 2.6 km3/a

Reversal of flow at current diffuse discharge zones (chotts) may cause aquifer salinization

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Great Artesian Basin: groundwater level declines and recovery

• Mean aquifer recharge: around 0.45 km3/year • Discharge by numerous artesian wells since 1887• Total discharge declines since 1917• Number of wells, however, kept increasing• Since 1997 well capping and piping programme• Aim: pressure recovery and preservation• Prognosis: around 0.211 km3/year saved by 2014

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Allocation of scarce groundwater

• Among potential users: – use a guiding principle (water rights, sector

priority, economic optimization, etc.)– zoning + assignment of functions– no or very limited control (e.g. water markets)

• In space:– negative impacts not independent of aquifer zone– use simulation model or simulation-optimization– uncontrolled

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Conjunctive management of groundwater and surface water

• Artificial recharge (Managed Aquifer Recharge - MAR)

• Watershed management (ponds, rainwater harvesting, surface water reservoirs)

• Baseflow replenishment

• Conjunctive use of groundwater and surface water

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Examples of artificial recharge

Sand dam in Kenya Huge recharge dam in Oman (5 km of crest length)

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Conjunctive use GRW - SW

Groundwater Demands Surface water basins sources

i = 1

i = 2

i = M

j = 1

j = 2

j = N

k = 1

k = 2

k = L

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Optimizing conjunctive use

t k

Q

i j i

tjij

tji

tjk

tjk

tik

tik

tkk

t

tk

SWRfSWfGWfdQQpr

z0

)()}()()({)1

1(max

Discount factor Profit from

water use Cost of groundwater Cost of

surface water Cost of

artificial recharge

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Salinity control First step to be made is assessing occurrence and origin

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Salinity control: control of upconing

• Upconing under a pumped well in response to decrease pressure in fresh domain

• Methods to prevent upconing:– skimming well (creating a stable mound)– scavenging well (dual pumping: saline and fresh water)

Fresh groundwater

Saline groundwater

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Salinity control: sea water intrusion

• Simultaneous outflow of fresh groundwater and intrusion of seawater

• Stronger fresh water flux reduces intrusion tongue• Note: Climate change/sea level rise may interfere

Coastal zone

Sea

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Irrigation-induced soil salination Volumes of water: R I ET

rainfall irrigation evapotransp.

Salt loads: Rcr Ici ETce

Control volume of soil: (undrained)

cc

capillary flow C

Soil salt quantity S

Mean annual soil water balance: R + I + C - ET = 0

Mean annual soil salt balance: Rcr + Ici +C cc - ETce = ΔS

Because ce < cr , ci,,, cc it follows: ΔS > 0

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Mechanism of soil salinity controlVolumes of water: R I ET

rainfall irrigation evapotransp.

Salt loads: Rcr Ici ETce

Control volume of soil: (drained)

Pcp

percolation flow P

Soil salt quantity S

Long-term soil salinity control (ΔS = 0 ) for Ici Pcp

Add “leaching requirement” to crop irrigation requirement and provide for drainage as needed

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Groundwater pollution: understanding water quality

• Observe current groundwater quality• Define the groundwater’s origin• Define water quality of recharge water• Define flow processes and patterns• Identify physical chemical and bacteriological

processes in the unsaturated zone• Identify presence, infiltration and/or injection of

contaminants• Identify modifications in the saturated zone (e.g.

solution, precipitation and other chemical reactions)

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Documented zones with excessive arsenic in groundwater (Smedley, 2008)

Groundwater quality constraints – either observed or probably present Risk of excessive fluoride in fresh

groundwater (IGRAC, 2005)

Natural groundwater quality variations are primarily related to geology

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Variations of water quality explained by flow systems

Polluted local flow systems

Unpolluted regional system of good water quality

Unpolluted but brackish regional system

Connate saline water

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Summary of the processesAtmosphere

Dissolution of gases and particles

Earth surfaceConcentration by pollution and by evapotranspiration

Saturated zone Dissolution and precipitation

Ion exchangeRedox reactions

AdsorptionGas generation and consumption

Interaction with other water bodies

Unsaturated zone Concentration by evapotranspiration

Dissolution and precipitationIon exchange

Redox reactionsAdsorption

Zone open to gasses

Influence of biosphere and soils

Presence of O2 and CO2

Zone closed to external gasses

Large residence times

At depth high T and p

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Contaminants

• Related to human activities, e.g.:– industry– traffic– agriculture (fertilisers, pesticides)– urban life– sanitary land fills

• Categories of sources: point-, line- and diffuse sources• Effects: toxicity and biodegradation• Migration of contaminants by underground transport

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Micro-pollutants: an emerging issue

• Two main categories:– Pharmaceuticals and personal care products (PPCPs)– Endocrine disruptive compounds (EDCs)

• Origin of EDCs: steroid-based food supplements, drugs, fungicides, herbicides + various household & industrial products

• Mode of dissemination: sewage, landfills, manure

• Concentration: nano- to pico-gram level (10-9 to 10-12 g/l)

• Effects: unknown yet, but potential capacity to interfere with hormones controlling human and animal growth and reproduction

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Contaminant transport

Pollutionsource

Pollution plume

Important processes:• Density flow• Convective transport• Dispersion

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Groundwater pollution control(preventive)

• Wellfield protection:

Zone IIIb

Zone IIIa II

I

• Aquifer protection:• control pollution at the source • avoid unnecessary risky activities above/in the aquifer • plan unavoidable risky activities where impacts are low• use vulnerability maps and monitor pollutants

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Dealing with pollution

Alternatives:– removing and disposing polluted soil/ water– in-situ remediation– technical isolation– hydrogeological isolation– treatment of polluted water– using polluted water where quality does not

matter

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Need for pollution control

Value of theresource

Aquifer vulnerability

Presence of

pollutants

Pollutionrisk

Needfor control

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Vulnerability: questions and factors

Topography

Soil properties

Unsaturated zone

Aquifer

Depth to phreatic level

Relation with surface water

Recharge

Do flows of water exist to

enable invasion of pollutants?

Do these waters infiltrate and migrate

easily ? Will pollutants decay?

(by adsorption, desintegration or

discharge)

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DRASTIC method for mapping vulnerability

Parameters:Depth to water tableRechargeAquifer typeSoil typeTopography (slope)Impact of unsaturated zoneHydraulic conductivity

Scores are calculated for each parameterfor each spatial unit

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DRASTIC vulnerability index

DRASTIC index =

5TD+ 4TR + 3TA + 2TS + TT + 5TI + 3Tc

Values between 26 and 220

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Groundwater level control

• Important in zones of shallow

groundwater tables:– phreatophytic agriculture– wetlands (“wet nature”)– build-up areas

• Control by surface water systems or by pumping

river

land

Drainage and subirrigation

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The Netherlands: Groundwater level control by manipulating surface water

• First stage: getting dry feet by drainage

• Second stage: drain during wet periods,

supply during dry spells (winter level, summer level)

• Third stage: establish ‘prefered groundwater

and surface water regimes’ (GGOR or PGSR)

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Defining GGOR or PGSR

OptimalRegime

Water system

Measures

Functions

Target satisfied ?

Regime accepted(GGOR)

Start analysis

Current regime

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Old and new approaches

Old approach:

• No limits to functions

• Evacuate surplus water as quickly as possible

• Provide allochtone water as needed

New approach:

• Adapt functions to conditions • Provide space to store surplus water (retention areas)

• Minimize supply of allochtone water

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Land subsidence

Groundwater abstraction

Decreasing pore pressure

Increasing effective pressure

Compression of porous layers

Land subsidence

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Introduction to groundwaterresources management

1 Introduction

2 Basic concepts and supporting subjects

3 Water resources plan development

4 Groundwater resources management issues

5 Implementing groundwater resources management

6 Case studies

Jac A.M. van der Gun

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Chapter 5: Implementing groundwater resources

management

• Institutional and regulatory requirements• Instruments and measures• Effects: prediction and monitoring

• How to play the game: ‘top-down’ law enforcement or a participatory approach?

• Crossing borders: transboundary aquifers

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Institutional and regulatory requirements

• Implementing agency (with a mandate)• Legislation and regulations• Groundwater management policy and plan• Monitoring systems• Financing mechanisms• Definition of communicacion/cooperation

with stakeholders (‘rules of the game’)

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Level PhysicalPlanning

WRM Environm.Management

NatureManagement

National BillPh.Pl.

BillWRM

EM Plan NM Plan

Provinces(12)

Regionplans

WRMplan

GWRMplan

EM PlanSoilManPlanGW ProtPlan

Waste dis-posal plan

NM plan

Water boards(58) WMPlan

Municipalities(504)

Functionplan

EM Plan

Planning effort in The Netherlands( strategic and operational )

Above these levels there are International Agreements and EU Directives

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Instruments and measures

• Categories of measures:– structural works (wells, dams, artificial recharge

works, etc.)– government funding/operation of facilities– law/ plan enforcement (including sanctions,

taxes, licenses, EIA, etc.) – incentives and encouragement of good practice

(incl. subsidies, water markets, privatization,etc.)

• Supply and demand management approaches for water quantity management

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Measures for groundwater storage management

• Due to external costs of groundwater pumping:

Q opt, private > Q opt, social

• Corrective measures to establish “social optimum”:

- restrict access (licenses)- increase private cost (taxes)

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Groundwater licensing

• Obligatory request for granting grw. user rights• To be submitted to GWRM agency• Basis for decision: GWRM plan• Different possibilities:

– decision depends on known parameters (area, purpose, quantity, etc.) immediate “yes” or “no”

– decision depends on predicted effects: then carry out study and compare predicted effects with maximum permissible decision

• After granting license: monitoring

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Obligations regarding groundwater

in the province of Gelderland Pump Abstraction

capacity rate

(m3/hr) (m3/ 3months)

• Declaring: > 1

• Registering: > 35

• Licensing: > 25 000

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Groundwater tariff

• Tariff breakdown:– Annual external cost per m3

• interference between pumpers• salination• pollution• land subsidence• wetland conservation & other

environmental impacts• user cost (scarcety premium)

– Annual GWRM cost per m3• studies & planning• licensing• collecting taxes• monitoring, etc.

• Tool for demand management and for recovery of external costs and management costs

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Measures for pollution control

• Pollution risk mapping• Land use planning and functional zoning• Prohibition of certain chemicals• Regulations for handling harzardous

substances and waste disposal• Obligatory treatment provisions• Proper sanitary waste disposal practices• Monitoring• Quick action in case of accidental pollution

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Who implements the plan?

• Should be decided upon in a pragmatic way, but consistent with local mandates and practices

• One extreme: centralised government action (‘top-down’)

• Other extreme: self-management by stakeholders’ WRM organisation

• Involvement of stakeholders usually increases succes rate

Informing

Inquiring

Consulting

Co-producing

Delegating

Selfruling

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Monitoring and adjustments

• Monitoring “effects” and “compliance” to be preferred over “monitoring the efforts spent”

• Corrective action and sanctions for violators of regulations

• Feed-back for plan adjustment, after comparing observed effects with predicted ones

• Water resources management follows planning cycles

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Crossing borders: transboundary aquifer resources management

• Aquifers: main reservoirs for subsurface storage of water and ‘highways’ for groundwater flow

• Many aquifers are crossed by political boundaries

• Potential cross-boundary interferences: changes in groundwater flows, levels, pressures, volumes and dissolved substances

• Invisible groundwater• Very slow flow• Why should we bother?

1. Eliminating potential sources of conflict2. Improving the overall benefit from

groundwater

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Important international initiatives on TARM

Emerging awareness on transboundary aquifer

issues

TARM/ISARM Programme – since 1997 (IAH & UNESCO-IHP)

Regional Inventories:Europe, Balkans, The Americas, Southern Africa, Caucasus/Central Asia, etc.

Mapping Transboundary Aquiferse.g. WHYMAP’s World Map (2006) and IGRAC’s TBA World Map (2009)

Regulatory & institutional efforts (e.g. ILC Draft Articles on the Law on TBAand EU Water Framework Directive)

Pilot projects (e.g. Guarani, North-Western Sahara, Iullemeden)

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318 inventoried transboundary aquifer systems

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Law of Transboundary Aquifers

• Souvereignity of aquifer States

• Equitable and reasonable utilization

• Obligation not to cause significant harm

• General obligation to cooperate

• Bilateral and regional agreements and arrangements

Main principles:

Present status:• Draft articles approved by UN General Assembly (Resolution

A/RES/63/124, December 2008)

• States are encouraged to consider them for water management

• Upgrade to legally binding framework convention desirable

good neighbour-

ship

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Global priorities and favoured approaches

• Millenium Development Goals

• Sustainable Development

• Transition to a Greener Economy

• Addressing Climate Change

Global policy priorities:

Favoured or emerging approaches:• IWRM

• Adaptive management

• Groundwater governance

• Integrated subsurface management

• Linking water management with other types of spatially defined management (‘getting out of the water box’ )

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Groundwater resources management in a nutshell

Groundwater

Problems?Opportunities?

Planning

Plan approval and acceptance

Implementation

Monitoring

Other policy fields

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Suggested Reading

http://www.unesco.org/new/fileadmin/MULTIMEDIA/HQ/SC/pdf/Groundwater%20and%20Global%20Change.pdf

Systematic description of the world’s ground- water systems, their resources, use and management, around 300 pages + maps and pictures (expected to appear by the end of 2012)

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... More suggested reading

Recommended