western cape reconciliation strategy study

• Serves more than 3 million people– Supply to Cape Town and some West Coast, Boland,

Swartland and Overberg towns• Irrigation

– In the Berg, Eerste and Riviersonderend rivers– Production of 50% of SA’s irrigated agricultural export

• High economic growth and migration into the system area• Infrastructure owned by the DWAF, City of Cape Town (CCT) &

Eskom• Berg Water Project under construction near Franschhoek

The Western Cape Water Supply System

• 90% runoff in Winter (May to Oct)• 70% requirements in summer (Nov to Apr)• 50% of system dams’ storage needed to store winter

water for usage in summer• 50% of system dams’ storage provides carry-over

storage for drought periods• Dams are operated to minimise spillage• Droughts are managed by progressively restricting

supplies

WCWSS characteristics

• To update and review water requirements and interventions to meet requirements

• To engage stakeholders and the general public• To develop toolkits to assist with the future

reconciliation of supply and requirement• To provide a guide for decision-making towards

effective reconciliation of supply and requirement• To recommend preparatory measures, actions and

assign responsibilities

PURPOSE OF THE RECONCILIATION STRATEGY

Management of Study

Professional Service ProviderSteering Committee

DWAF HO

DWAF RO

CCT

Saldanha Mun.

Provincial Dept.

of Agric

Province

National Water Resource Planning

Study Management

RECONCILIATION STRATEGY STUDY

Public participation

Selected

Stakeholder

input

Reconciliation StrategyCCT WC/WDM Strategy

CCT WSDP

CCT’s Integrated Development Plan (IDP)

Provincial Integrated Development Plan

Berg Catchment Management Strategy

Other WSDPs

Institutional Planning Process

NEWSLETTER 1

PUBLIC MEETINGTo identify and provide feedback on interventions

NEWSLETTER 2

PUBLIC MEETINGTo provide feedback on interventions for comment

August 2005: Screening of Interventions Workshop

Refine reconciliation scenarios and strategy content through stakeholder workshops and technical focus groups

Input from the Berg and Breede-Overberg CMA Reference Groups

NEWSLETTER 3Summary of strategy to public for comment

Determine and analyse a range of implementation scenarios

Input from the Berg and Breede-Overberg CMA Reference Groups

NEWSLETTER 4Obtain public feedback on scenarios through

press release and newspaper advert

PUBLIC MEETINGTo present the Reconciliation Strategy and

selected interventions for further study

Strategy Steering Committee to consider comments

DWAF WRFMCCCT Portfolio CommitteeCCT Mayco and CouncilBerg CMA Reference Group

PUBLIC PROCESS FOLLOWED

STRATEGY THEMES

Strategy

Protection and

Management

Comparison of supply

and requirement

Selection of intervention

s

Stakeholder Engagement

Implementation and

Performance monitoring

Monitoring and

Information Management

Water Availability

Water Requirements Water Use

Efficiency

Reconciliation Reconciliation StrategyStrategy

9 Themes each containing

•Key issues

•Objectives

•Approach

•Action

•Responsibility

•Programme

Scenario Planning for Reconciliation of Supply

and Requirement

Treated Effluent use

Supporting Reports

WC/WDM

Determination of Future Water Requirements

Structure of StudyKey Reports

Bulk Water Supplied by the CCT

130

180

230

280

330

380

430

480

530

580

630

1978 1981 1984 1987 1990 1993 1996 1999 2002 2005 2008 2011 2014 2017 2020

Mil

lio

n c

ub

ic m

etre

s/an

nu

m

High Water Requirement Curve

Actual Low Water Demand Curve

(DWAF/CCT Agreement)

Previous unconstrained curve

Low Water Requirement Curve

CCT 8-yr WC/WDM Strategy

Additional Longer-term WC/WDM

Groundwater Interventions

Surface Water Interventions


Desalination

Options/ Interventions Identified




Treated effluent use

Desalination

Pressure Reduction Leak Detection and Repair Meter management

and replacement Consumer awareness School Education Plumbing retro-fit prg Support for large consumers Re-use: Parks and Industry Management Information

System Upgrade telemetry system







Desalination

Tariffs, metering and

credit control

Eliminate AFUs

Promotion of private

boreholes & wells

Leak detection

Water Efficient Fittings

User Education






Desalination

Newlands Aquifer

Cape Flats Aquifer

West Coast Aquifers

TMG Aquifer






Desalination

Voëlvlei Phase 1

Michell’s Pass Diversion

24 Rivers Dam

Upper Wit River Diversion

Raise Steenbras Lower Dam

Upper Molenaars






Desalination

Treated Effluent use Irrig./ind

Dual Reticulation

Commercial Irrig. Exchange

Treated Effluent use to

Potable standards

Berg River Exchange






Desalination

CCT Pilot Plant

Desalination Plant

WC/WDM and Supply Interventions in order of lead time

CCT 8-year WC/WDM Strategy (44.8)WC/DM: P romotion of private bore & wells (3.6)

WC/DM: User Education (10)WC/DM: P romotion of grey water use (1)

WC/DM: Use of Water Efficient Fittings (7.9)WC/DM: Eliminate auto flush urinals (4.2)

WC/DM: Tariffs, metering and credit control (20)WC/DM: Domestic leakage repair (2.2)

TMG Scheme 1 (after CCT exp. phase) (20+) West Coast Aquifers (13.8)

WC/DM: P ressure management (16.7)Cape Flats Aquifer (18)

WC/DM: Leakage detection and repair (15.6)Newlands Aquifer (7)

Reuse- Irrig./Industrial (20)Reuse - dual reticulation (28)

24 Rivers Dam (1.8)Lourens River Diversion (19)Eerste River Diversion (8.3)

TMG Scheme 1 (after CCT pilot) (20+)Upper Wit River Diversion (10)

Voëlvlei P hase 1 (35)Re-use - Commercial Irrigation (5)

Brandvlei to TWK transfer (41)Re-use - potable Study Option 1 (60.1)

Michell's P ass Diversion (4m3/s) (35.7)Upper Molenaars (To Berg River Dam) (27)

Desalination 1 Generic (22+)Raise Lower Steenbras (25)

Upper Campanula Dam (Option 1) (13.5)Dam at Misverstand (40)

Lower Wit River Dam (29.5)

P re-Feasibility Decision Feasibility Decision Env. ApprovalsDesign Implementation First Water

Scenario Planning

The objective of the Scenario Planning Process is to identify, evaluate and assess alternative groupings and phasing of interventions so as to determine the potential impacts and benefits of possible combinations of interventions to reconcile water supply and requirement in the WCWSS, up to 2030.

SCENARIO 1 SCENARIO 2 SCENARIO 3

ILLUSTRATES IMPACT OF WC/WDM ON TIMING OF IMPLEMENTATION OF SUPPLY INTERVENTIONS

NO WC/WDMCCT WC/WDM

strategy implemented

CCT WC/WDM strategy

implemented & additional WC/WDM

interventions

SCENARIO DESCRIPTION

Scenario1No WC/WDM, but all supply interventions can be implemented

Objective: To determine the impact of not implementing WC/WDM

KEY FINDINGS

Supply Intervention required by 2011 Due to long lead times earliest supply intervention could only be implemented by 2014Shortfall in supply between 2011 and 2013


Scenario 2

CCT WC/WDM strategy implemented as well as supply interventions.

Objective: To determine the impact of implementing the CCT’s WC/WDM strategy

KEY FINDINGS

Supply intervention required by 2015Implementation of CCT’s WDM strategy and programme delays supply intervention by 4 years


Scenario 3

CCT WC/WDM strategy and programme implemented as well as additional longer term WC/WDM interventions and supply interventions.

Objective: To determine the impact of implementing all the WC/WDM interventions

KEY FINDINGS

Implementation of comprehensive WC/WDM could potentially delay supply intervention until approx. 2019Comprehensive WC/WDM (100% successful implementation) can effect a saving of approx 100 million m3 of water per annum by 2019

ILLUSTRATES IMPACT OF LOWEST URV SELECTION AS WELL AS IMPACT OF IMPLEMENTING ECOLOGICAL RESERVE AND POTENTIAL IMPACT OF CLIMATE CHANGE

SCENARIO 7 SCENARIO 8 SCENARIO 9

CCT WC/WDM strategy

& Lowest URV Interventions

CCT WC/WDM strategy,

Lowest URV Interventions

& Ecological Reserve


Lowest URV Interventions

& Possible Climate

Change

6

8

9 10

7

12 13

14

16

17


Scenario 7

CCT WC/WDM strategy implemented, thereafter selection based on URV.

Objective: To determine the impact of selecting interventions based on lowest URV

KEY FINDINGS

A mix of supply and demand interventions are available for selection in order to offset the anticipated shortfall in supply in 2015.Net present value of this option is R1 092 million

Scenario 7: CCT WC/WDM strategy implemented, thereafter selection based on URV

No. WC/WDM Intervention Supply Intervention

17 TMG Scheme 1

16 TMG Scheme 2

15 WC/DM: User Education

14 TMG Scheme 3

13 24 Rivers Dam

12 West Coast Aquifers

11 WC/DM: Use of Water Efficient Fittings

10 Cape Flats Aquifer

9 Treated Effluent - Irrig./Ind

8 Voëlvlei Phase 1

7 Upper Wit River Diversion

6 Newlands Aquifer

5WC/DM: Promotion of private boreholes &

wells

4 WC/DM: Leakage detection and repair

3 WC/DM: Eliminate auto flush urinals

2 WC/DM: Tariffs, metering and credit control

1 CCT WC/WDM 8-year strategy

6

10

12 13

7 8 9

14

18 19

17

16


Scenario 8

CCT WC/WDM strategy implemented, thereafter selection based on URV with the ecological Reserve being phased in for existing water resources

Objective: To determine how the implementation of the ecological Reserve will impact on the selection of interventions

KEY FINDINGS

The yield of the existing water resources decreased by approx. 46 million m3.Supply and demand interventions are available Net present value of this option is R1 263 million. Cost of implementing additional interventions in order to offset the anticipated decrease in system yield is approximately R171 million in today’s terms.

Scenario 8: CCT WC/WDM strategy implemented, thereafter selection based on URV with the ecological Reserve being phased in for existing water resources


19 Lourens River Diversion

18 Raise Lower Steenbras Dam

17 TMG Scheme 1

16 TMG Scheme 2


14 TMG Scheme 3

13 24 Rivers Dam

12 West Coast Aquifers


10 Voëlvlei Phase 1

9 Treated Effluent -

Irrig./Industrial



6 Newlands Aquifer

5 WC/DM: Promotion of private bore & well





16

9

6

10 13

12

7 8

18 19

17

14

20 21

22


Scenario 9

CCT WC/WDM strategy implemented, thereafter selection based on URV with the potential for climate change being factored in

Objective: To determine how climate change could impact on the selection of interventions

KEY FINDINGS

The yield from the existing water resources and future water resources was assumed to decrease by approx. 107 million m3.Supply and demand interventions are available for selectionCost of impact is approx. R572 million

Scenario 9: CCT WC/WDM strategy implemented, thereafter selection based on URV with the potential for climate change being factored in


Treated Effluent use - dual reticulation

Eerste River Diversion

Lower Wit River Dam


18 Raise Lower Steenbras

17 TMG Scheme 1

16 TMG Scheme 2


14 TMG Scheme 3

13 24 Rivers Dam

12 West Coast Aquifer (Langebaan Road)



9 Voëlvlei Phase 1

8 Treated Effluent use- Irrig./Industrial


6 Newlands Aquifer


4 WC/DM: Promotion of private boreholes & wells




”CONSERVATIVE SELECTION” AND IMPACT OF IMPLEMENTING ECOLOGICAL RESERVE AND

POTENTIAL IMPACT OF CLIMATE CHANGE

SCENARIO 10(A) SCENARIO 10(B) SCENARIO 10(C)

CCT WC/WDM strategy

& conservative Selection of Interventions


conservative Selection of

Interventions, Ecological Reserve &

Climate Change

All WC/WDM interventions, conservative Selection of

Interventions, Ecological Reserve &

Climate Change

• Additional longer-term WC/WDM interventions – Equates to approx 50% of the modelled potential WC/WDM

saving– Uncertainties regarding actual savings achievable

• Newlands Aquifer– Small yield– Potential impact on river flow and existing users

• Cape Flats Aquifer– Perceived O&M concerns of sustainability of operating

wellfield in a relatively high density area

• Upper Wit River Diversion– Potential difficulties in obtaining environmental approvals

Scenario 10 (a) to (c)“Conservative Selection”

Reasons for omitting specific interventions:

6

3

2

5 4

7

9

8


Scenario 10 (a)

CCT WC/WDM strategy, thereafter selection based on a conservative selection of interventions

Objective: To determine the impact of selecting a “conservative portfolio”

KEY FINDINGS

Supply interventions would have to be “fast tracked”.To avoid “fast tacking” WC/WDM would have to be successfully implemented Net present value of this option is R1 844 million (this is in comparison to a NPV of R742 million for Scenario 7, which was based on least cost selection and not a selection based on considerations of practicality and sustainability).

Scenario 10 (a): CCT WC/WDM strategy, thereafter selection based on a conservative selection of interventions


9 Treated Effluent use - potable

8 Upper Molenaars (To Berg River

Dam)

7 TMG Scheme 2


5 Raise Lower Steenbras (fast

tracked)

4 Treated Effluent use -

Irrig./Industrial

3 Voëlvlei Phase 1 (fast tracked)

2 TMG Scheme 1 (fast tracked)


3 4 5

7

6

2

8

9

10


Scenario 10 (b)

CCT WC/WDM strategy, thereafter selection based on a conservative selection of interventions including potential impacts of ecological Reserve and climate change

Objective: To determine how the implementation of the Reserve and the potential for climate change could impact on the selection of interventions

KEY FINDINGS

Supply interventions would have to be “fast tracked”.Net present value of this option is R 4 477 million. Cost impact of climate change and implementing the Reserve is approx R 2 633 million

Scenario 10 (b): CCT WC/WDM strategy, thereafter selection based on a conservative selection of interventions including potential

impacts of ecological Reserve and climate change


10 Desalination 1 Generic

9 Treated Effluent use - potable

8 Upper Molenaars (To Berg

River Dam)


6 Raise Lower Steenbras Dam

(fast tracked)


4 Voëlvlei Phase 1 (fast tracked)

3 Teated Effluent use - Irrig./Industrial (fast tracked)



9 6

12

15

11

14

10

13


Scenario 10 (c)

All WC/WDM interventions implemented, thereafter selection based on a conservative portfolio of interventions, including potential impacts of ecological Reserve and climate change

Objective:To determine how the implementation of longer term WC/WDM interventions impacts on Scenario 10(b)

KEY FINDINGS

Additional WC/WDM interventions delay supply intervention by 3 yearsNet present value of this option is R2 718 million. Benefit of delaying desalination by implementing additional WC/WDM interventions is approx R1 759 million

Scenario 10 (c): All WC/WDM interventions implemented, thereafter selection based on a conservative portfolio of interventions, including potential impacts of ecological Reserve and climate change


15 Treated Effluent use- potable

14 Upper Molenaars (To Berg River

Dam)


12 TMG Scheme 1

11 TMG Scheme 2

10 Raise Lower Steenbras Dam (fast

tracked)

9 Voëlvlei Phase 1



6 Treated Effluent - Irrig./Industrial



3WC/DM: Promotion of private boreholes

& wells

2WC/DM: Adjustment of water tariffs,

metering and credit control


ILLUSTRATES IMPACT OF LOW WATER REQUIRMENT CURVE

SCENARIO 11

Low Water Requirement Curve

CCT WC/WDM strategy &

intervention selection based on

URV


Scenario 11

The low water demand requirement curve formed the basis of this analysis. CCT WC/WDM strategy implemented, thereafter selection based on URV

Objective: To determine how the low water requirement curve and the least URV selection criteria could impact on the selection of interventions

KEY FINDINGS

The Low Water Requirement curve would delay the next intervention (after the implementation of the CCT’s WC/WDM strategy) until 2024.

CONCLUSIONS

• Successful implementation of CCT’s WC/WDM 8-year strategy and programme is essential

• Additional longer-term WC/WDM interventions just as important

• Groundwater options very important – especially TMG

• Treated effluent use has massive potential. Treated effluent for potable use may be required as early as 2020

• Desalination of seawater as long term “back-up”

• Feasibility studies should commence on both demand and supply interventions to ensure reconciliation of supply and requirement

• A Strategy Committee should be formed to ensure implementation of the strategy

Interventions Selected for Additional StudyCCT WC/WDM Strategy and

ProgrammeMichell's Pass Diversion

WC/WDM Adjustment of water tariffs, metering and credit control

Newlands Aquifer

WC/WDM Eliminate auto flush urinals Cape Flats Aquifer

WC/WDM Promotion of private boreholes and wells

West Coast Aquifer Recharge (Langebaan Road Aquifer)

WC/WDM Leakage detection and repair

Upper Wit River Diversion

WC/WDM Use of water-efficient fittings

Raising Steenbras Lower Dam

WC/WDM User education Lourens River Diversion Scheme

Voëlvlei Phase 1 Treated effluent use

Upper Molenaars Diversion

Strategy Committee

A Strategy Committee should be established with the following objectives:

• To ensure that the strategy is relevant and updated, • To monitor and co-ordinate the implementation of the

relevant actions identified in the strategy, and • To make recommendations on long-term planning

activities required to ensure reconciliation of requirement and available supply in the WCWSS area

A support group should be established to provide administrative scientific and technical support to the Strategy Committee

WC Provincial Government ( 5 REPRESENTATIVES)

Local Authorities ( 5 REPRESENTATIVES)

City of Cape Town: 3 representatives

West Coast District Municipality: 1 representative

Cape Winelands District Municipality: 1 representative

Department of Water Affairs and Forestry ( 9 REPRESENTATIVES)

Regional Office: 3 representatives

Integrated Water Resource Planning: 3 representatives

Water Use Efficiency: 1 representative

Water Resource Infrastructure Branch: 2 representatives

Catchment Management Agencies (when established) ( 2 REPRESENTATIVES)

Berg CMA : 1 representative

Breede-Overberg CMA: 1 representative

Water User Associations ( 2 REPRESENTATIVES)

Berg WUA: 1 representative

Breede-Overberg WUA: 1 representative

Representation on Strategy Steering Committee

23 REPRESENTATIVES

RECOMMENDATIONS

It is recommended that:• A Strategy Steering Committee be formed to oversee the

implementation of the Strategy

• The CCT and other WSAs should implement their WC/WDM strategies and programmes

• The CCT and other WSAs should develop integrated policies on treated effluent use and determine the full future potential for treated effluent use

• The CCT should continue with the TMG Feasibility Study and Pilot Project and the Desalination Pilot Plant as these could be significant future water resources

• The DWAF and the CCT should initiate studies on a number of interventions to ensure the reconciliation of supply and requirement

Thank you

Thank you

ANY QUESTIONS

western cape reconciliation strategy study

Documents