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Challenges Facing the Implementation of a Water
Demand Management Programme
Challenges Facing the Implementation of a Water
Demand Management ProgrammeWillem Wegelin
WRP Consulting Engineers, South Africa
AFRICAN UTILITY WEEK, ICC DURBAN22-25 February 2010
Willem WegelinWRP Consulting Engineers, South Africa
AFRICAN UTILITY WEEK, ICC DURBAN22-25 February 2010
BackgroundBackground
A 15% reduction in urban water consumption for Gauteng has been set to limit potential water restrictions by 2014
Water resources to KZN metropolitan and coastal areas have reached maximum capacity.
Eastern Cape is experiencing major drought
A 15% reduction in urban water consumption for Gauteng has been set to limit potential water restrictions by 2014
Water resources to KZN metropolitan and coastal areas have reached maximum capacity.
Eastern Cape is experiencing major drought
3
Importance of Vaal SystemImportance of Vaal System
Supply water to 60% of economy, 45% of population
Mines and industry on Eastern Mpumalanga Highveld
Bulk of Eskom’s coal fired power stations
Gauteng
NW and FS goldfields
Kimberley
Large irrigation schemes
Supply water to 60% of economy, 45% of population
Mines and industry on Eastern Mpumalanga Highveld
Bulk of Eskom’s coal fired power stations
Gauteng
NW and FS goldfields
Kimberley
Large irrigation schemes
Existing Transfer Schemes
Proposed Transfer Schemes Mokolo Catchment
Crocodile CatchmentVaal Catchment
Integrated Vaal River System
0
200
400
600
800
1,000
1,200
1,400
1,600
1,800
2001 2003 2005 2007 2009 2011 2013 2015 2017 2019 2021 2023 2025
Wa
ter
Re
qu
ire
me
nts
(m
illi
on
m3/a
nn
um
)
Years
High Scenario
Actual Water Use
15% WC/WDM Scenario
Water Requirements from Rand Water for:
Johannesburg, Ekurhuleni, City of Tshwane,
Emfuleni, Mogale, Govan Mbeki, Randfortein, Rusternburg
Gauteng Key Urban Demand ProjectionGauteng Key Urban Demand Projection
Reconciliation Scenario (High)LHWP and TWP
Reconciliation Scenario (High)LHWP and TWP
Eradicate unlawful irrigation
Jana Dam Yield
Mielietuin Dam Yield
Polihali Dam Yield
Earliest possible delivery date
Reconciliation Scenario (High)15% WC/DM, LHWP and TWP
Reconciliation Scenario (High)15% WC/DM, LHWP and TWP
Polihali Dam Yield
Mielietuin Dam Yield
Eradicate unlawful irrigation
Earliest possible delivery date
Result of Excessive LeakageResult of Excessive Leakage
Excessive water demand
Intermittent supply and poor service delivery
Reluctance to pay for services
Increasing municipal debt
Unhygienic living conditions
Maintenance backlogs prevent WDM implementation
Excessive water demand
Intermittent supply and poor service delivery
Reluctance to pay for services
Increasing municipal debt
Unhygienic living conditions
Maintenance backlogs prevent WDM implementation
Strategy DevelopmentStrategy Development
Setting of realistic target
Strategy should be based on facts- Metered consumption- Potential savings should be realistic
Identify key water loss contributing factor/s and address the problem
Setting of realistic target
Strategy should be based on facts- Metered consumption- Potential savings should be realistic
Identify key water loss contributing factor/s and address the problem
Interventions (1)Interventions (1)
Leak detection and repairPressure managementSectorisationBulk meteringConsumer metering and billingCommunity awarenessTraining and capacity buildingRetrofitting programmes
Leak detection and repairPressure managementSectorisationBulk meteringConsumer metering and billingCommunity awarenessTraining and capacity buildingRetrofitting programmes
Interventions (2)Interventions (2)
Performance monitoring- Minimum night flows- Flow and pressure logging
Telemetry systemsWater auditsWater balance calculationsCustomer care centresBylaws and tariff structures
Performance monitoring- Minimum night flows- Flow and pressure logging
Telemetry systemsWater auditsWater balance calculationsCustomer care centresBylaws and tariff structures
Management metersManagement meters
Management meters not operational
Management meters operational but not read
Management meters read but not documented and analysed
What are we metering (not sectorised)
Management meters not operational
Management meters operational but not read
Management meters read but not documented and analysed
What are we metering (not sectorised)
Supply problems (1)Supply problems (1)
Bulk supply not operationalNetwork cannot sustain peak demandResults in intermittent supplyConsumers leave taps open “waiting for water”Intermittent supply results in negative pressuresNegative pressures result in waterborne diseases and damage pipe seals
Bulk supply not operationalNetwork cannot sustain peak demandResults in intermittent supplyConsumers leave taps open “waiting for water”Intermittent supply results in negative pressuresNegative pressures result in waterborne diseases and damage pipe seals
Supply problems (2)Supply problems (2)
Cannot expect consumer to pay for intermittent supply
Cannot expect consumer to save water if he / she is on intermittent supply
Cannot implement most WC/WDM interventions if on intermittent supply
Cannot expect consumer to pay for intermittent supply
Cannot expect consumer to save water if he / she is on intermittent supply
Cannot implement most WC/WDM interventions if on intermittent supply
Intermittent SupplyIntermittent Supply
Most intermittent supply problems caused by closed valves in the network
Clockwise or anti-clockwise closing valves
Uncertain? – leave valves half open
Lack of engineering / trouble shooting skills
Most intermittent supply problems caused by closed valves in the network
Clockwise or anti-clockwise closing valves
Uncertain? – leave valves half open
Lack of engineering / trouble shooting skills
Pressure managementPressure management
Lack of knowledge on operation
Lack of maintenance
Network problems. Low pressure problems solved by increasing the PRV outlet pressure
Compromised by cross connections
Lack of knowledge on operation
Lack of maintenance
Network problems. Low pressure problems solved by increasing the PRV outlet pressure
Compromised by cross connections
Commissioning PRV installationsCommissioning PRV installations
Low pressure
complaintsOpen PRV
Reset PRV“Solve”problem
Bad job
Stable set PRV
Set PRV
Consumer metersConsumer meters
Community acceptancePoor contractors or not performingMetered but not captured on financial systemMetered but not billedMetered and billed but unreliableBroken metersPoor meter readingsTechnology does not necessary solve problems
Community acceptancePoor contractors or not performingMetered but not captured on financial systemMetered but not billedMetered and billed but unreliableBroken metersPoor meter readingsTechnology does not necessary solve problems
Community Awareness Community Awareness
Should be long term programme driven by the municipalityShould have clear policies & proceduresShould have infrastructure, people and logistics to support programme- Customer call centre- Technical teams to fix leaks- Complaints should be resolved ASAP
Political and institutional support
Should be long term programme driven by the municipalityShould have clear policies & proceduresShould have infrastructure, people and logistics to support programme- Customer call centre- Technical teams to fix leaks- Complaints should be resolved ASAP
Political and institutional support
ConclusionConclusion
Existing operations and maintenance of water distribution systems impact heavily on implementation of WC/WDMStaff knowledge and capabilities impact heavily on successful project implementation and sustainabilityBudget allowance must be made for proper commissioning and sustaining of interventionsHuge potential for job creation through WDM
Existing operations and maintenance of water distribution systems impact heavily on implementation of WC/WDMStaff knowledge and capabilities impact heavily on successful project implementation and sustainabilityBudget allowance must be made for proper commissioning and sustaining of interventionsHuge potential for job creation through WDM