SECOND EDITION: 2004 PREFACE The first version of these Guidelines was issued in 1999. The original guidelines were specifically developed to give technical guidance to engineering and other experts who were responsible for developing RDP type water supply projects on behalf of the Department of Water Affairs and Forestry.
There have however been a number of fundamental changes since 1999, which prompted the Department to update the guidelines.
Firstly, a greater emphasis has been placed on the provision of basic sanitation services, necessitating the inclusion of guidelines on basic sanitation infrastructure.
Secondly, Government funding for water services is now channelled directly to Local Government through the Municipal Infrastructure Grant. With few exceptions, municipalities will in future be the main developers of basic services infrastructure.
Thirdly, much experience has in the interim been gained in the development of water services infrastructure and these lessons needed to be captured in the guidelines.
Finally, the adoption of the Strategic Framework for Water Services has impacted on the definition of basic services and on the approach to developing these services.
The purpose of this updated 2004 version of the guidelines is primarily to pass on the experience of national government in the development of water and sanitation services, and especially the planning and design of water and sanitation infrastructure, to local government. It is believed that this document will accelerate the learning process of those in local government who are taking full responsibility for water services development for the first time. It is also believed that these guidelines will be just as useful to those who wish to refine their existing knowledge.
While these guidelines are mainly technical in nature, the wider issues such as the social aspects and the operation and maintenance of water services infrastructure will be addressed in other documents.
A large number of experts from the Department of Water Affairs and Forestry and other organisations have selflessly contributed their experience towards the development of these guidelines. It is acknowledged that these guidelines would not have been possible without their contribution.
TABLE OF CONTENTS
1 INTRODUCTION 9
1.1 Purpose of guidelines 9
1.2 Definitions of minimum norms and standards 10
1.3 Project development life cycle 11
2 LEGISLATION AND POLICY 13
3 INSTITUTIONAL ARRANGEMENTS 14
3.1 Introduction 14
3.2 Deciding on and contracting with a water services provider 14
3.3 Bylaws and other requirements 15
4 PLANNING 16
4.1 Introduction 16
4.2 National reference plan 16
4.3 Water services development plan 18
4.4 Feasibility studies and technical reports 18
5 DESIGN CRITERIA 27
5.1 Introduction 27
5.2 Summary of design and planning criteria 27
5.3 Water availability 29
5.4 Power availability and alternative pump drives 29
5.5 Guidelines for economic optimisation of pump - pipeline sizing 29
5.5.1 Economic analyses 30
5.5.2 Pump and pipe sizing for small borehole schemes 30
6 DESIGN REPORT, DRAWINGS AND SPECIFICATIONS 32
6.1 Introduction 32
6.2 Design report 32
6.3 Sustainability 33
6.4 Drawings 33
6.5 Standard drawings 34
6.6 Special drawing requirements and operating and maintenance manuals 35
6.7 Design specifications 35
7 BOREHOLES 36
7.1 Borehole development steps 36
7.2 Borehole pumps 37
7.3 Borehole monitoring and other equipment 38
8 DAMS AND WEIRS 40
8.1 Dams 40
8.2 Weirs 40
8.3 Approved professional engineer 41
8.4 Outlet works of dams and weirs 41
8.4.1 Depth of water draw off 41
8.4.2 Outlet pipe systems 42
8.4.3 Intake entrance 42
8.4.4 Control valves for outlet works 42
8.4.5 Maintenance cranes 45
8.4.6 Screening of intake works 46
9 WATER TREATMENT WORKS 47
9.1 General 47
9.2 Potable water quality 47
9.3 Selection of appropriate treatment process 47
9.4 Recommended loading rates and design parameters for water treatment process units 47