Water consumption trends and domestic demand forecasting

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Water consumption trends and domestic demand
forecasting
WATERSAVE Network Second Meeting, 4 December 2001

• F Memon D Butler
• Urban Water Research Group
• Department of Civil and Environmental Engineering
  
• Imperial College of Science, Technology
  Medicine, London

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Will the available freshwater resources be
sufficient to meet the future demand if current
water consumption trends remain unchanged?
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To answer this

• Pace of population growth
• Emerging socio-economic trends
• Climate change

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(No Transcript)
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Water stress observed in 1985
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Expected change in water stress in 2025 (using
1985 as the reference year)
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Per capita water consumption in some countries
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Water consumption frequency distribution
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Factors influencing domestic demand

• Household size (occupancy)
• Household type (flat, detached, semi detached)
• Age group (Retired, adult, children)
• Seasonal variations

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Impact of household size on per capita consumption
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Water consumption by different micro-components
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Micro-component use frequency
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Approximate peak frequency of use and time
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Appliance daily discharge pattern
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Water consumption by micro-components
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Reduction in water consumed by washing machine in
last 30 years
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Reduction in water consumed by dishwashers in
last 30 years
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Water saved and potential for further saving
(England and Wales)
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Water saved and potential for further saving
(England and Wales)
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Demand Forecasting

• Purposes
• Factors
• Techniques

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Demand Forecasting (Purposes)

• Strategic planning
• Investment appraisal
• Operations planning
• Appraisal of demand-management policies and
  innovations

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Demand Forecasting (Purposes)

• Demand management in crisis periods
• Calculation of future price trends as efficiency
  signals and
• Some supply forecasting

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Demand Forecasting (Factors)

• Spatial and temporal variability
• Water conservation policies
• Characteristics associated with various
  appliances used (i.e. ownership, frequency and
  volume of water consumed per use)

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Demand Forecasting (Factors)

• Lessons learnt from the forecasting techniques
  used in the past
• Past water consumption trends
• Acceptability to the regulator and
• Feasibility w.r.t. cost and data collection and
  validation requirements.

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Demand Forecasting (Techniques)

• 1.Techniques that build conceptually and require
  a limited amount of data to produce future
  projections in water demand. These techniques are
  usually used for long-term forecast

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Demand Forecasting (Techniques)

• 2.Techniques that require extensive data
  collection. The data is used to extract the
  statistical relationships and infer the rules
  that will govern the extent of demand. These
  methods are used for short-term forecast

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Demand Forecasting (Techniques)

• Micro-component analysis
• Micro-component group analysis
• Forecasting based on socio-economic scenarios
• Statistical methods
• Neural Networks

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Demand Forecasting Techniques (Micro-component
analysis)
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Demand Forecasting Techniques (Micro-component
group analysis)
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Demand Forecasting Techniques (Socio-economic
scenario based)

• Alpha
• Beta
• Gamma
• Delta

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Demand Forecasting Techniques (Socio-economic
scenario based)

• Scenario Alpha (Provincial Enterprise) Under
  this scenario, the preference to the
  environmental issues and social equity is low due
  to slow economic growth and lack of investment.

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Demand Forecasting Techniques (Socio-economic
scenario based)

• Scenario Beta (World market) This scenario
  assumes a high level of economic growth but
  little consideration is given to social equity.
  The concern for environment is low particularly
  in financially feeble sections of the community.

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Demand Forecasting Techniques (Socio-economic
scenario based)

• Scenario Gamma (Global sustainability) Sustained
  economic growth and social equity are the main
  feature of this scenario. There is a considerable
  investment in environmental research, which would
  produce clean technologies that help in resource
  conservation

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Demand Forecasting Techniques (Socio-economic
scenario based)

• Scenario Delta (Local stewardship) In this
  scenario, leadership at local level takes
  collective action to resolve environmental
  problems.

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Expected change in water demand in 2025 for each
scenario
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Acknowledgements

• Paul Jeffrey (Cranfield)
• David Howarth (Environment Agency)
• Gareth Rondel (Anglian Water)
• Paul Herrington (Water Economist)