INTRODUCTION

Urbanization is profoundly changing the face of many nations. Rapidly growing cities bring new possibilities, but also new challenges. One of the most vital of these challenges is the provision of piped water and of efficient sanitation for an ever-growing urban population.

In Nepal, as in many other countries, sanitary installation represents a new trade. It was with the intention of giving useful hints and guidelines to the practitioners of this trade that the first edition of this book was published.

This fourth edition is the result of a steady demand for the book in many countries. The opportunity has been taken to review and improve the entire text. Drawings have been redone and the section on drainage has been considerably enlarged. As in earlier editions, more than one solution is given for certain problems because some norms differ from country to country. In all cases, however, care was taken to use standard terminology.

In preparation of this edition, special thanks are due to Mr. Laxmi Bahadur Manandhar, Principal of M.T.C. and Mr. A. Wiederkehr of Helvetas, Zurich. Thanks are also due to Mr. Ram Prasad Shah, Draftman; Mr. Ram Kumar Thapa, Office Asst.; Mr. Purna Man Shrestha, Office Incharge. Grateful acknowledgement is owed to SSIV (Schweiz. Spenglermeister und Installateur Verband) for much additional information on soil and waste water drainage. The English language was checked and corrected by Mr. Nick Gregory.

This book is intended to be used as manual and reference work by practising sanitary engineers. We hope that it will continue to be a valuable and trusted companion to many planners and practitioners in Nepal and abroad.

Ben Dolf/Programme Director
Helvetas Nepal

Patrick Leu/Co-Principal
MTC, Balaju