FOREWORD

The potential socioeconomic benefits of urban stormwater drainage are huge: improved health and quality of life in existing low-income human settlements, and the availability of additional usable urban land reclaimed by drainage projects which can be used for human settlements or industry and commerce. Properly designed and maintained stormwater drainage projects almost always increase substantially land values.

This report has been prepared in response to the increasing need for those involved in urban land use and management to develop efficient and cost-effective urban stormwater drainage programmes. It focuses specifically on the socioeconomic and engineering factors involved in such programmes, with special emphasis on appropriate strategies for proper operation and maintenance, as well as providing sound advice on planning and design. Operation and maintenance of stormwater drainage projects has all too often been neglected in the past - frequently it has been done only in response to emergency situations: this is both costly and inefficient. Detailed engineering advice is given in the annex to the report; this is basically a stormwater design manual.

The very rapid increase in urbanization that is currently occurring in developing countries is an irreversible fact of life facing urban planners and city engineers. The demand for urban land is correspondingly enormous and I am confident that this publication will be invaluable to those professionals involved in urban land management and urban stormwater drainage. These two disciplines together have the ability to regenerate vast areas of land in developing country cities, land that is currently unable to be fully utilized due to inadequate or non-existent stormwater drainage. I hope therefore that this report will serve as a useful starting point in increasing awareness of the need for appropriate strategies for urban stormwater drainage, so that the supply of usable urban land increases.

I gratefully acknowledge the contribution of Mr John Macklin in providing specific inputs to UNCHS (Habitat)'s present research efforts leading to the completion of this report.

Dr Arcot Ramachandran
Under-Secretary-General
Executive Director