In most of the developed countries there is continuous water supply.
They operate their
system by direct pumping with a practice of 100% consumer metering and telescopic tariff.
However, in many developing countries like India, water tariff is not volumetric.
Way back in 1949, the Environmental Hygiene Committee constituted by the Government of
India recommended to discourage intermittent water supply and promote 24x7 continuous
water supply systems in urban areas with the objective to prevent contamination of drinking
water in piped water distribution system.
The demerits of an intermittent system and merits of 24x7 system are shown in Box-1.
Box-1: How Superior is pressurized 24x7 water supply system?
Intermittent 24x7 System
1) High health risks 1) Stops contamination.
2) Leakage control is passive. 2) Reduction in medical bills
3) No demand management 3) Leakage control is active.
4) Few meters 4) Demand management is possible.
5) Flat water rates 5) 100% consumer metering
6) Wastage of treated water 6) Telescopic tariff
7) Service level is poor. 7) Reduces consumption.
8) Service level cannot be measured. 8) Equitable distribution and enough
9) Inequitable distribution of water pressure
and inadequate pressure 9) Financial sustainability.
10) Less financial sustainability 10) Life of network increases
11) Large doses of chlorine 11) Better demand management
12) Capacities underutilized. 12) Better service level
13) Valves- wear and tear 13) Consumer satisfaction
14) More manpower- zoning 14) Water is accessible to poor.
15) Large sizes of pipes 15) Willingness to pay- even in slums.
16) Supply hours affect poor. 16) Time for rewarding activities.
17) Storage is required. 17) Attracts industries.
18) Pay for pumping for roof top
storages.
19) Meters go out of order.
20) Store and throw water
3. APPROACH PROPOSED
The present systems in the country operate on intermittent mode, the goal should be to
ultimately achieve the world-class standard of continuous water supply with metered
functional tap connections to all households with a smooth transition. The Guideline
recommends an approach for planning, design and upgradation of urban water supply
system to convert existing intermittent supply to 24x7 water supply system.
4. DECENTRALIZED PLANNING
Decentralised planning system solves the complex problem by breaking it into smaller sub-
problems. The city is divided into manageable zones called as operational zones(OZs)
which are further divided into sub zones called as District Metered Areas (DMA)s. DMAs are
progressively chosen for providing 100% consumer metering and with bulk meter at
entry of DMA. Leakages in chosen DMAs are identified, gets quantified
and are removed. The leakages in all the DMAs should be stopped and water
that otherwise would be lost, is saved which helps in increasing hours of supply. This is the
basic principle of converting intermittent systems in to 24x7 systems. Each individual DMA is tackled
in this way and their combined success in increasing water supply duration finally converts intermittent
system of city to 24x7 water system.
This document provides the detailed procedure for conversion of intermittent system to pressurized
continuous 24x7 system. This includes a procedure for determining optimum boundary of operational
zone, establishing DMAS with various tests required for making ithydraulically discrete,
comprehensive design of transmission main, rationaldesign capacity of service tanks for 24x7 system,
retrofitting and rehabilitation of water distribution networks, proper material selection, control valves
for 24x7 system.
5. GIS BASED HYDRAULIC MODELLING
It is observed that water supply systems in lndia are not being planned, designed using Geographic
lnformation System (GlS). Without GlS, it is not possible to assign ground elevations and demands to
large number of nodes of distribution system. The Ministry has published Advisory on "GlS Mapping
of Water Supply and Sewerage lnfrastructures," which may be referred to for the same.
Like GlS, without comprehensive hydraulic model of a city, no reforms can take place in the water
supply sector. Hydraulic modelling is an essential tool for conversion to continuous system. Besides
this, the basic building blocks of 24x7 system, i.e., operational zones and DMAS need GIS based
hydraulic model for design.
It is observed that the technique and sci-art of rational allocation of demands to the nodes of
distribution pipe network is not uniformly practiced in the country. This Guideline describes the method
for realistic distribution of the total design population/ total design demands in the various wards of the
city based on equivalent area, forecasted density and by using GIS technology so that nodal demands
are accurately given for hydraulic modelling. lntegration of Geographic lnformation System (GlS) with
appropriate network software is also discussed in this guideline.
6. INCLUSION OF DESIGN PROCEDURES FOR 24X7 WATER SUPPLY SYSTEMS
Following design procedures are discussed in this Guideline:
1) As discussed above, design of operational zones and District Metered Areas (DMA)s are included
in this Guidelines. Uniqueness of the present decentralised approach is to consider one
operational zone for each service reservoir. This is achieved by grouping the reservoirs as per
characteristics of lerrain which becomes easily possible by use of GIS tool.
2) lf the operational zone is not sized properly, it leads to malfunctioning of reservoirs like emptying
and oveilowing.
3) There are many inappropriate practices existing in distribution systems of the cities in lndia. For
example, in existing distribution system of many cities, it is observed that two or three existing
reservoirs are observed to combinedly serve a single excessively large operation zone. This
Guideline discusses how to correct such snags.
4) lf DMAs within operational zones are not properly established, water audit is not possible.
Prioritization of the leak repair program is also not possible in absence of DMAs in the existing
distribution system.
5) One of the neglected areas in water supply is the equitable distribution of water in the distribution
systems. Equitable distribution of water with designed pressure is the important aspect of 24x7
water supply. lt is achieved by Whole-to-Part approach, in which two stages are involved- (a)
equitable distribution from Master Balancing Reservoir (MBR) to service reservoirs and (b)
equitable distribution from service reservoir to DMAs.
6) Equalization of pressures (residual heads) at Full Supply Level (FSL) of service tanks is also a
grey area. Equalization of heads helps in effective and equitable supply of water to various service
reservoirs in city by the transmission mains.
7) Currently, many cities are being transformed into Smarf Crtrbs. This Guideline describes the
procedure how to economically design pipelines on both sides ofthe roads by utilizing these roads
as boundaries for operational zones and DMAs.
8) Pressure management strategies in Water Distribution Network is important. The methods of
pressure management are discussed.
9) NRW compulation is an important parameter in 24x7 systems. Estimating physical and
commercial losses in the distribution system is an essential component of water balance in NRW
reduction program. This Guideline discusses procedure to compute such losses. For this purpose,
importance of connecting the meters and flow control valves to the Supervisory Control and Data
Acquisition (SCADA) system is also discussed.
10) This guideline recommends to consider a minimum residual head of 17 M at highest spot in the
DMA of Class I and Class ll cities/towns and 12 M head for Class lll-Vl Towns. A peak Factor of
2.50 is recommended for all Cities and Towns irrespective of population size.
11) The case studies of 24x7 water supply projects for the cities such as Puri, Pune and Coimbatore
are included in the guidelines. The per capita cost of the project and other best practices may be
referred to in these case studies.
I am confident that guidellnes will help State PHEDS/ Water Boards/ Jal Nigams/Urban Local Bodies
(ULBs) for effective planning, design and implementation o'f 24x7 waler supply projects in urban areas
of the Country.
I express my best wishes and appreciate the efforts of Dr. Sanjay Dahasahasra, Former Member
Secretary, Maharashtra Jeevan Pradhikaran and Dr.Rajesh Gupta, Professor & Head, Civil Engineering
Department, VNIT Nagpur, Expert Committee Members for providing technical support in preparation of
the guidelines. I would also like to extend my sincere gratitude to other Expert Committee members who
have reviewed and enriched the document. I would also thank Dr. Ramakant, Deputy Advise(pHE) &
Member Secretary of the Expert Commiftee, Shri. Vipin Kumar Patel, Smt. Chaitra Devoor, Assistant
Advisers, cPHEEo, special lnvitee Dr. Kalpana Bhote, Assistant chief Engineer, MJp, Nagpur for their
untiring efforts in coordinating and reviewing the Guidelines. I would also like to extend my specialthanks
to GIZ for being the Knowledge Partner and Experts appointed by GlZ. I would atso like to thank
lnternational Experts who contributed in preparing the Guidelines.
Dr. M. Dhinadhayalan
Table of Content
Foreword
Preface
Executive Summary
Table of Contents (i)
List of Figures (iv)
List of Tables (vi)
Abbreviations (vii)
Chapter 1: Introduction 1-7
1.1 The Concept of Decentralised Urban Water Supply System 1
1.2 Present Status of Water Supply in India 1
1.3 Disadvantages of Intermittent Water Supply 2
1.4 Reasons for Intermittent Water Supply 3
1.5 Shifting from Intermittent to 24x7 Water Supply 4
1.6 Need of the Guidelines 4
1.7 Planning and Design 5
1.7.1 Conversion of Intermittent to 24x7 Water
Supply System 5
1.7.2 Strategy 5
1.8 Activity Chart for Change of Mode 6
1.9 Outcomes 7
1.10 Cost of Conversion 7
Chapter 2: Design Parameters 8-26
2.1 Data for Design 8
2.1.1 General Data 8
2.1.2 Collection of Available Data 8
2.2 GIS Mapping 9
2.3 Customer’s Underground Tank 9
2.4 Break Pressure Tank and Master Balancing Reservoir 9
Chapter 3: Hydraulic Model 27-33
3.1 Hydraulic Modelling 27
3.2 Requirement of Hydraulic Model 27
3.3 Happening Inside Hydraulic Model 27
3.4 Integration of GIS with Hydraulic Mode 28
3.4.1 Creation of GIS Base Map and Existing 28
Infrastructure
3.4.1.1 Creation of Base Map 28
3.4.1.2 Locating Existing Infrastructure on Base Map 29
3.4.2 Network Software Component 30
3.5 Building a Model 30
3.5.1 Combining Existing and New Pipes 31
3.5.2 Assigning Elevations and Demand to Nodes 31
3.5.3 New Reservoirs 31
3.6 Creating Operational Zones and DMA 31
3.7 Adding Isolation Valves 31
3.8 Scenario Management 32
i
3.9 Method of Analysis 32
3.10 Model Calibration 33
3.11 Use of Simulated GIS Hydraulic Model in Retrofitting 33
Chapter 4: Operational Zone and DMA 34-47
4.1 Operational Zone (OZ) 34
4.2 Design Criteria for Operational Zones 34
4.3 Computation of Optimum Demand that a Tank can Serve 34
4.3.1 Fixing Boundary of Operational Zone 35
4.3.2 Mapping Operational Zone Boundary in 35
Hydraulic Model
4.3.3 Achieving Required Minimum Nodal Pressures 38
in Operational Zones of Existing ESRs
4.3.4 Bad Practice Establishing Very Large OZ 39
4.4 District Metered Area (DMA) 39
4.4.1 The Need of DMA 39
4.5 Design Criteria for Establishing DMA 40
4.5.1 Size of DMA 40
4.5.2 Design of DMA 41
4.6 DMA Category 41
4.6.1 Establishing DMA Based on Number of 42
Connections
4.7 Equitable Flow and Pressure 42
4.7.1 Whole-to-Part Approach 42
4.8 One Inlet for Each DMA 44
4.8.1 Equitable Pressures within DMA 44
4.9 Pipelines on Both Sides of Roads 44
4.10 Pressure Management 45
4.10.1 Pressure Zone of Tank 45
4.10.2 Layout of the Network 45
4.10.2.1 Layout in Hilly Areas 45
4.11 Distribution of Water by Direct Pumping 46
Chapter 5: Optimization of Diameters of Pipes 48-54
5.1 Novel Methodology 48
5.2 Basic Planning Prior to Optimization 48
5.3 Design Principles for Optimizing Diameters 49
5.4 The New Technique 49
5.5 Staging Height of ESR 51
5.6 The Methodology 52
5.6.1 Optimization of Pipes in all Operational Zones 52
Chapter 6: Transmission Mains 55-65
6.1 Objectives 55
6.2 General Principles in Design of Transmission Mains 55
6.3 Pumping Mains 57
6.4 Transmission Gravity Mains 57
6.4.1 Incorrect Practice and Its Solution 58
6.5 Optimization of Capital Cost of Transmission Mains using 59
Hydraulic Model
ii
6.6 Optimisation of Energy Cost by Optimization of LSL of MBR 59
6.7 Optimisation of Energy Cost by Inlet-Outlet at Bottom of MBR 61
6.7.1 Level of Bottom of MBR For Optimization 61
of Energy Cost
6.8 Equalisation of Residual Heads at FSL of All ESRs 62
6.8.1 Moving Node Method 62
6.8.2 Design of Branched Pumping Main – Optimization 64
of Diameters
6.9 Surge Protection for Transmission Mains 65
Chapter 7: Reduction of NRW 66-73
7.1 Reducing Non-Revenue Water 66
7.2 Impacts of NRW 66
7.3 Water Audit 67
7.4 Water Balance 67
7.4.1 Components of Water Balance 68
7.5 Computation of NRW by STEP Test 69
7.6 Methods for Reducing Unaccounted for Water (UfW) 69
7.6.1 By 100% Consumer Metering and Telescopic 69
Tariff
7.6.2 Leak Detection 69
7.6.2.1 Methods of Leak Detection 69
7.7 Leakage Reduction Measures 70
7.8 Response Time 71
7.9 Estimating Losses 71
7.9.1 Estimating Physical Losses 71
7.9.2 Estimating Commercial Loss 72
7.10 Leak Repair Program 72
7.11 SCADA Attached to DMA 73
7.12 DMA management 73
Appendix A: Break Pressure Tank (BPT) 74
Appendix B: Case Study of Pune 24x7 Water Supply 78
Appendix C: Case Study of Coimbatore 24x7 Water Supply 81
Appendix D: Case Study of Puri 24x7 Water Supply 84
Appendix E: Measures to Increase Residual Nodal Pressure 100
Appendix F: Information of Pressure in Other Countries 103
Bibliography 104
iii
List of Figures
Figure 1.1 & 1.2 Intermittent system-contaminant entering in the pipe ....................... 3
Figure 1.3 Implementation steps ................................................................................. 5
Figure 1.4 Strategic measures .................................................................................... 6
Figure 1.5 Activity chart showing a road map for change of mode .............................. 6
Figure 3.1 Hydraulic model required for carrying out reforms………………………....27
Figure 3.2 Tools used in the hydraulic model ............................................................ 28
Figure 3.3 Creation of hydraulic model...................................................................... 29
Figure 3.4 Small network created by the Model Builder ............................................ 30
Figure 3.5 Segments in operational zone .................................................................. 32
Figure 4.1 Operational zone with DMAs .................................................................... 34
Figure 4.2 Logic for computation of optimized demand of tank ................................. 35
Figure 4.3 Logic for fixing boundary of operational zone of Tank-1........................... 36
Figure 4.4 Network whose operational zones are to be fixed .................................... 37
Figure 4.5 Selection of nodes in first iteration ........................................................... 38
Figure 4.6 Selection of nodes in third and final iteration ............................................ 38
Figure 4.7 Operational zones 1 and 2 are fixed for tanks 1 and 2, respectively ........ 38
Figure 4.8 A typical DMA........................................................................................... 39
Figure 4.9 Types of DMA .......................................................................................... 41
Figure 4.10 Equitable flow from MBR to ESRs .......................................................... 43
Figure 4.11 Equitable flow from ESR to distribution network through DMAs ............. 43
Figure 4.12 Separate inlets for each DMA ................................................................ 44
Figure 4.13 Pressure zones in hilly city ..................................................................... 46
Figure 5.1 Network .................................................................................................... 50
Figure 5.2 Pipe diameters before and after optimization ........................................... 51
Figure 5.3 Iterative process of optimizing diameters ................................................. 53
Figure 6.1 Typical pumping main .............................................................................. 57
Figure 6.2 Determination of most economical pipe diameter .................................... 57
Figure 6.3 Typical gravity transmission main ............................................................ 58
Figure 6.4 Old transmission network (red) and new transmission network (grey) ..... 58
Figure 6.5 Iterative design of pipe diameters of Transmission mains ........................ 59
Figure 6.6 Inlet pipes to DMAs .................................................................................. 60
Figure 6.7 Inlet, outlet arrangement of MBR ............................................................. 61
Figure 6.8 Logic of computing optimization of LSL of MBR ....................................... 62
Figure 6.9 Branch pipe with two segments................................................................ 63
Figure 6.10 Equalization of residual pressures for ESRs .......................................... 64
Figure 6.11 Branched pumping main ........................................................................ 64
Figure 6.12 Sample result of water hammer analysis of a pumping main ................. 65
Figure 7.1 NRW values of different cities in India ...................................................... 66
Figure 7.2: Vicious circle of NRW…………………………………………………………67
Figure 7.3: Virtuous circle of NRW .... ……………………………………………………67
Figure 7.4: Flowchart for reduction in real losses of water .... …………………………70
iv
