RURAL INDUSTRIES PRIVATE BAG 11
INNOVATION CENTRE PHONE 393. 392, 448 & 449

KANYE BOTSWANA

SMALL SCALE DESALINATION FOR REMOTE
AREAS OF BOTSWANA

By R. YATES and T. WOTO

MAY 1988

FINAL REPORT OF A RESEARCH PROJECT FUNDED BY THE INTERNATIONAL DEVELOPMENT RESEARCH CENTRE, OTTAWA, CANADA 1984 - 1987

CONTENTS

Acknowledgements
PREFACE
Executive Summary

PART ONE - INTRODUCTORY

1.1 INTRODUCTION
1.2 PROJECT TEAM AND DEVELOPMENT
1.3 THE FUTURE OF THE DESALINATION PROGRAMME

PART TWO - THE WATER SITUATION IN THE DESERT

2.1 THE NEED FOR WATER
2.2 AFFECTED GROUPS - THE KALAHARI REMOTE AREA DWELLERS
2.3 THE RADS : AN ETHNIC PERSPECTIVE
2.5 THE RADP AND SMALL-SCALE DESALINATION
2.6 THE DROUGHT SITUATION IN THE DESERT AND RELATED RELIEF PROGRAMMES

PART THREE - THE TECHNOLOGY

3.1 OPTIONS TO PROVIDE WATER
3.2 WOODBURNING STILLS
3.3 SOLAR DESALINATION
3.4 MEXICAN STILLS
3.5 BRICK STILLS
3.6 OTHER TYPES OF SOLAR STILL
3.7 PERFORMANCE OF THE STILLS
3.8 OPERATION AND MAINTENANCE OF STILLS
3.9 INSTALLATION OF STILLS
3.10 COSTS AND ECONOMIC ANALYSIS OF SOLAR STILLS

PART FOUR - THE SETTLEMENTS

4.1 CHOICE AND NATURE OF SETTLEMENTS
4.2 THE RESEARCH SETTLEMENTS
     4.2.1 Case Study 1 : Khawa
     4.2.2 Case Study 2 : Lokgware
     4.2.3 Case Study 3 : Zutshwa

PART FIVE - TRAINING AND TECHNOLOGY ACCEPTANCE IN THE FIELD

5.1 TRAINING AND TECHNOLOGY ACCEPTANCE AMONG THE RADS
5.2 FIELD EXPERIENCES WITH WOOD-BURNING STILLS
5.3 FIELD EXPERIENCES WITH SOLAR STILLS
     5.3.1 KHAWA
     5.3.2 ZUTSWHA
     5.3.3 LOKGWARE : a case of technology rejected
5.4 FINAL EVALUATION SURVEYS : KHAWA AND ZUTSHWA

PART SIX - TRAINING AND ACCEPTANCE WITHIN THE ADMINISTRATION

6.1 TRAINING AND ACCEPTANCE AT LOCAL AND CENTRAL GOVERNMENT LEVEL
6.2 EVALUATION SURVEY

REFERENCES
APPENDIX 1 - A MAINTENANCE MANUAL FOR SOLAR STILLS PRESENTED BY R. YATES
APPENDIX 2 - LAYOUT AND CONSTRUCTION MANUAL FOR THE MK II MEXICAN STILLS
APPENDIX 3 - SALT PRODUCTION AT ZUTSHWA
APPENDIX 4 - RESOLUTIONS AT A DESALINATION SEMINAR HELD AT THE RURAL INDUSTRIES INNOVATION CENTRE IN KANYE FROM 10TH - 13TH AUGUST 1987
APPENDIX 5 - SUMMARY OF PROJECT FINDINGS

Acknowledgements

The authors would like to offer thanks to all those who have helped with this project.
First of all to IDRC for supporting the project and for taking the trouble to visit and see how things are in the field. To Ron Alward who came as a consultant from Brace Research Institute and continued to give support and advice. To MR J.D. Nyatanga for his tireless support in the field, and to all the other staff at Kgalagadi District Council who have spent time helping us. To those in Central Government, particularly MR C. Lindblom of Ministry of Local Government and Lands for their tolerance and time. To all the management and staff of RIIC who have given help and advice without seeming to interfere.
Especially to the other members of the desalination team - Judge Tlhage (field officer), Mooka Moetse (extension officer), Tefo Marcho (technician), Karabo Modise (builder) and Piet Cooper (driver) who each spent about 1800 hours driving or being driven around the desert, and whose efforts in temperatures from 44° C to -9° C in sun, hail, dust and rain, night and day, have carried the project to completion.
Finally thanks to the people of Khawa, Lokgware and Zutshwa who were always honest, hospitable and helpful to us.

PREFACE

This is the final report of a three year project to evaluate and then to introduce a new technology for water treatment in certain areas of Botswana. Solar desalination was already well developed and established elsewhere, so the task was to adapt it to the local conditions and to generate enough confidence for it to be accepted.

Many lessons were learnt in the course of the project not only about desalination but also about how to get a technology accepted and how much time and effort it takes to adapt an old technology to a new situation. However appropriate a technology may seem, there will always be problems which occur in real life which may influence its acceptance.

The information contained in this report is sufficient to make informed Decisions about future desalination work in Botswana. The account of how the project was run and what sort of problems occurred will also be relevant to the implementation of other projects.

Executive Summary

One hundred and thirty desalination units made up of two types of solar still, two of woodburning still and one reverse osmosis unit were tested in remote settlements in the Kgalagadi District in Botswana. The only alternative sources of drinking water at these settlements was that delivered by council trucks.

The objective of the project was to see if desalination in any form would be suitable for use in the remote area settlements in Botswana.

In two of the three test sites, the solar still technology was well accepted, in the third it was not properly used and was finally removed. Reasons for the failure include lack of commitment by the villagers and the absence of a salt water supply to the stillsite. An attempt was made at this site to introduce stills for individual households instead of as a communal installation, but this system was even less satisfactory and is not recommended.

Extensive training was given to the end users and to those in local and central government whose support was needed. These training programmes were essential to the final acceptance of the technology.

Throughout the project detailed surveys were carried out to assess the impact of, and attitudes to the technology. By the end of the project those settlements where desalination was accepted had benefited from other council services which could only be introduced once water was available.

It was concluded that solar desalination is an appropriate technology for some remote areas of Botswana, and the money saved by not having to truck in water soon justifies the investment. For successful operation the stills should be set up as a communal installation with a full time operator to look after them. Failure to keep the stills correctly filled will lead to their rapid deterioration.

The technology has been accepted as a viable means of supplying drinking water and already a further site with 176 stills is being constructed. Two more sites have also been planned, all using funds from the drought relief programme.

A summary of the findings of the project and a list of resolutions passed by government and council staff at the end-of-project seminar, are given in Appendices 4 and 5 at the end of this report.