Course 5

Water Demand Measures

Teacher Saroj Sharma

About Saroj Sharma

Saroj Kumar Sharma graduated in Civil Engineering with distinction in 1988 (M.R.Engineering College, University of Rajasthan, India), completed his MSc in Sanitary Engineering with distinction in 1997 (IHE Delft, The Netherlands) and PhD in Groundwater Treatment in 2001 (Wageningen University and IHE Delft, The Netherlands). He is specialized in water supply engineering - water quality, treatment and distribution.

He has 19 years of professional and academic experience in planning, design, implementation, and operation and maintenance of urban, semi-urban and community-based rural water supply projects. He has worked with several government agencies, international consultants and donors (UNICEF, WHO, ADB, WB) in various water supply projects in different parts of the world.

His teaching and research interests are in the field of physicochemical treatment processes (filtration and adsorption based processes), natural treatment systems (bank filtration and soil aquifer treatment), water transport and distribution (water loss management, urban water demand management, corrosion of water pipes) and decentralized water supply systems for small towns and urban poor areas.

http://www.unesco-ihe.org/iu/staffmember/roj 2

Contents



Introduction



Urban water demand management measures



Case studies

3

Part A

INTRODUCTION

4

  

Traditional Water Supply Management

Traditional supply driven water management Water needs are “requirements” that must be met and not the “demands” that are changeable.

New facilities and structures are developed using available sources to meet perceived “increasing” water needs. Traditional approach has led to over-use of the resources, over-capitalization, pollution and other problems of varying severity.

Old paradigm of designing water supply with little attention to demand determinants, pricing structures and financial policies is not sustainable. 5

From water supply management (WSM) to water demand management (WDM)

 WDM approach places water demands themselves, not structural solutions, at the centre of concern.

 WDM recommends the development of large, capital intensive structures only after other possible options for lowering or mitigating the proposed demands have been fully analyzed.

 WDM and conservation represent the cheapest form of easily available water. Particularly in the areas where additional demands are being placed on water resources which are already stretched to their limit.

6

What is Water Demand Management?

Water demand management (WDM) refers to any socially beneficial action that reduces or modifies average or peak water withdrawals or consumption consistent with protection or enhancement of water quality. WDM can be defined as a strategy to improve efficiency and sustainable use of water resources taking into account economic, social and environmental considerations. WDM corresponds to use of price, quantitative restrictions and other devices to limit the demand of water. 7

Benefits of WDM

 Reduces water demands (30% - 50%) with no deterioration in life style or service level.  Significantly reduces capital requirements for expansion of water supply and lowers operating costs (particularly chemicals and energy)  Reduces generation of pollutants, and therefore the requirements for new or expanded wastewater treatment systems.

 Facilitates expansion of the coverage of available fund  Enhances the development and adoption of new technologies.  Leads to financially sustainable water systems 8

Part B

WATER DEMAND MEASURES

9

Water Demand Management Measures

   WDM relies upon a range of measures (tools and techniques) which can be divided into Economic Socio-political, and Structural and operational 10

Economic Measures

Economic techniques depend on  Incentives such as rebates, tax credits and  Disincentives such as real cost, penalties, fines Example: Realistic Water Pricing  A direct means of controlling water demand and generating revenues to cover costs  Should be complementary to other measures of water demand management 11

Socio-political Measures

 Policies and Laws  Economic policies, government regulations, standards on appliance redesign and marketing: − policy to promote water saving devices − encouraging water savings in industries  Effective public/stakeholder education and awareness measures  Wise use of water; direct restrictions on use 12

Structural and Operational Measures

Structural and operational measures are used to achieve better control over water demand.

metering, retrofitting, controlling flow (rationing) and recycling reduction of UFW, leakage detection and repair use of water efficient devices water use restrictions during periods of water shortages 13

Approaches for Water Demand Management

     Increase system efficiency Increase end use efficiency Promoting distributed sources of supply Substitute resource use Improve the market on resource usage 14

Demand Management Measures

 Increase system efficiency  No change in usage, but change in system operation  Leak detection and repair, pressure reduction  Increase end use efficiency  Less resource use by consumers by using water advertising, education and use of water efficient devices (low volume flush, shower heads, dish washer, washing machine etc)  More efficient watering of public open spaces  Water efficiency in the planning, design and construction of homes and buildings 15

Demand Management Measures

 Promoting distributed sources of supply  Provide service via local resource not being used  encourage rainwater use and grey-water reuse  Substitute resource use  Provide same service without resource use  Waterless sanitation, low water- use garden plants and shrubs, plants adapted to local rain fall  Improve the market on resource usage  inform consumers about full cost of resource  full cost pricing, universal metering, information on impact of excessive water use 16

Reduction and Control of Unaccounted for Water

  

Reduction and Control of UFW

Substantial savings can be achieved and requirement of extension water supply facilities can be avoided or minimised by reducing unaccounted-for water. (specifically leakage detection and control) By reducing UFW water agency will be in better financial situation and will be stronger position to achieve its financial self-sufficiency and long term sustainability.

A low rate of unaccounted-for water is one of the best overall indicators that a water utility is successful.

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What is Unaccounted-For-Water?

Definition Unaccounted-for water (UFW) represents the difference between "net production" (the volume of water delivered into a network) and "consumption" (the volume of water that can be accounted for by legitimate consumption, whether metered or not). UFW = “net production” – “legitimate consumption” 19

Non-Revenue Water

Non-revenue water (NRW) represents the difference between the volume of water delivered into a network and billed authorized consumption.

NRW = “Net production” – “Revenue water” = UFW + water which is accounted for, but no revenue is collected (unbilled authorized consumption). 20

Components of Unaccounted-For Water

Unaccounted-for water Physical loss (Real loss) Pipe breaks and leaks Storage overflows House connection leaks Commercial loss (Apparent loss) Metering Errors Water Theft Billing Anomalies 21

Standard Terminologies

Source:

System Input Volume Authorised Consumption Water Losses Billed Authorised Consumption Unbilled Authorised Consumptiion Apparent Losses Real Losses Billed Metered Consumption (including water exported) Billed Unmetered consumption Unbilled Metered Consumption Unbilled Unmetered Consumption Unauthorised Consumption Metering Inaccuracies

IWA (2000)

Leakage on Transmission and/or Distribution Mains Leakage and Overflows at Utility’s Storage Tank Revenue Water Non- Revenue Water Leakage on Service Connections up to point of Customer Metering All quantities in m 3 /year

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Four components of an active real loss management program

More efficient leak detection Existing real losses Economic level Improved response time for leak repair Unavoidable real losses Pressure management and level control Improved system maintenance, replacement, rehabilitation

Source:

Thornton (2002)

Four components of an active apparent loss management program

Reduction of meter error by  Testing,  Sizing  Replacement Existing apparent losses Economic level    Reduction of theft by  Education  Legal action Prepay measures Pressure limitation Flow control Unavoidable apparent losses Reduction of   human error  Training  Standardizing Reporting Auditing Reduction of   computer error by  Auditing  Checking Routine analysis Upgrade

Source:

Thornton (2002)

Part c

CASE STUDIES

Case Study: Singapore (1)

Limited water resources, importing water from Malaysia Strong emphasis on

Water Conservation

as well as

Management of Water Distribution System

Water Demand Management Approach  Keeping unaccounted-for water low   Conservation in customers’ premises Tariffs and use of economic incentives and disincentives 26

  

Case Study: Singapore (2)

Keeping unaccounted-for water low leak detection and repair, mains replacement and rehabilitation, minimising illegal connection Conservation in customers’ premises water saving devices, promoting use of other sources (rain water, sea water), encouraging water reuse, consumer education Tariffs and use of economic incentives and disincentives rates reviewed periodically, rate structured to encourage conservation only approved pipe and fittings are allowed to be used in water supply system water service works are done by licensed workers only 27

Evolution of UFW in Singapore (1989-1999)

6 4 2 12 10

10.6

9.5

7.7

8

6.7

6.4

6.0

6.2

5.9

4.9

4.7

5.1

0 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999

Source:

Yepes (1995); PUB Singapore (2001) 28

Singapore - Volume of Water Sold and Revenues (1994) Consumer Residential Commercial and Industrial Government Shipping Total Percent of Volume 47.3 32.0 19.9 0.8 100% = 456 Mm 3 Percent of Sales Relative Tariff 40.3 47.1 10.6 0.85 1.47 0.53 2.0 2.50 100% = $US 237 million 1.00 = $US 0.52/m 3

Source:

Yepes (1995) 29

Case Study: Rous Regional WDM Program

New South Wales, Australia – Population 70000         Demand management program included the following  Pricing and billing reform Leakage detection and repair Rebates & give-aways for water efficient shower heads Point of sale rebate for front loading washing machines Discounted residential retrofit Free water audit for non-residential customers A water efficient demonstration house and garden Effluent reuse in a new village A school education program 30

Case Study: Brittany, France

 A major pilot project in 7 cities of Brittany, France [ Brest, Lorient, Pontivy, Quinter, Rennes, Morlaix (St Martin-des-Champs) and Vannes ] (total population – 800, 000)  Project activities Information campaign (users and professionals); Letters to domestic users; Tests & installation of various water-saving devices Investigations of leakage in the public distribution system and in private households.

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Water Savings in Seven Pilot Cities in Brittany, France

Source: Sustainable Water Use in Europe (EEA 2001) 32

Case Study: Decreasing Network Losses in Zurich, Switzerland

  Network monitoring and leakage control - Annual inspection of at least 40 % of the network Regular network flushings & hydrant controls - Around 10,000 hydrants are checked, flushed and repaired biannually.  Periodic area-wise network maintenance Valves, street surface boxes, signs, etc., are locally inspected, cleaned, made accessible or restored.  Periodic pressure surge measurements and stray current measurements To maintain the up-to-date situation of performance analysis 33

Decreasing Network Losses in Zurich

 Specific water loss decreased from 0.57 m 3 /h/km in 1985 to 0.22 m 3 /h/km in 1995.  Cost of maintenance operation

Component Repairs Man-hour /km/year 5 Swiss Frank/ km/year 5000 Preventive Maintenance 25 3000 Renewal Total 25 55 15000 23000

Source:

Sustainable Water Use in Europe (EEA 2001) 34

Decreasing Network Losses in Zurich 12 10 8 6 4 2 0 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 Year

Source:

Sustainable Water Use in Europe (EEA 2001) 35

Case study – WDM in Boston, USA

 In Boston, impending costs of supplying water to the city led officials to implement a Long Range Water Supply Program (LRWSP) to cut down on water use.  Between 1988 and 1993, LRWSP reduced the average daily demand for water from 1.2 million to 0.9 million m 3 .  The program focused on detecting and repairing leaks, metering, retrofitting showerheads and toilets with more efficient technologies, protecting water sources from pollution, and building support for the program among city, residents through outreach and education.  These reductions eliminated the need to develop new supplies - saving hundreds of millions of dollars--and the water system is operating within its safe yield for the first time in 20 years (40). 36

Reducing water demand in Sydney

364 329 http://www.sydneywater.com.au/html/AER2000/html/imp_water/demand_manag.htm

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Water Supply and Demand with and without Demand Management

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Bibliography

ADB (1997)

Second Water Utilities Data Book: Asian and Pacific Region

. Edited by McIntosh, A.C. and Yniguez, C.E. Asian Development Bank.

Baumann, D. D., Boland, J.J. and Hanemann, W.M. (1998)

Urban Water Demand Management and Planning

. McGraw-Hill Inc.

EEA (2001) Sustainable Water Use in Europe. European Environmental Agency. www.eea.eu.int

OECD (1999) Household water pricing in OECD Countries.

Prasifka, D.W. (1994)

Water Supply Planning

. Krieger Publishing Company, Florida, USA. UK (1994) UK Water Industry: Managing Leakage.

Interpreting Measured Night Flows.

Yepes, G. (1995) Reduction of Unaccounted-for water: The job can be done! ESD, World Bank.

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Web Resources on Water Conservation

1. Environmental agency UK – Save water www.environment-agency.gov.uk

2.

Conserve Water – Melbourne Water Australia http://conservewater.melbournewater.com.au

3. Water Efficiency Clearing House - AWWA www.waterwiser.org

4.

USEPA – Water Use Efficiency Program www.epa.gov/owm/water-efficiency/ 5.

Environment Canada www.ec.gc.ca/water/en/manage/effic/e_weff.htm 6.

7.

Public Utilities Board http://www.pub.gov.sg

Water Demand Management Forum http://www.idrc.ca/waterdemand/ 40