7th International Rainwater Catchment Systems Conference
"Rainwater Utilization for the World's People"
Beijing , China - June, 1995

Preface

Changming Liu
Chairman, Local Organizing Committee

Rainwater utilization has had a history of several thousand years and it will soon be seen as a prosperous way to solve water shortage problems in the coming century. Based on the establishment of rainwater utilization, the connotation of rainwater resources and its catchment systems have been become much more widely extending towards sustainable water exploitation since the establishment of the International Rainwater Catchment Systems Association in 1983 in Hawaii. Rainwater can he used in both direct and indirect ways because rainfall transforms into different hydrological states with diversified patterns of water interactions. For instance, roof catchment systems represent the direct collection of rainwater, while ponds or reservoirs can receive water indirectly from surface runoff and subsurface flow as so-called direct runoff and inter-flow resulting from a rainfall within a given catchment. The extended connotation of rainwater utilization can also include artificial recharge of shallow groundwater by using rainfall in terms of building up a groundwater reservoir for pumping wells and a soil water reservoir for agricultural production. In addition, a new idea of rainwater collection may concern weather modification, i.e. artificial rain. Therefore, the substantiation of the concept of rainwater resources and elaboration of the connotation concern a broader prospect of rainwater utilization. In this context, it is expected that the rainwater catchment systems may be turned into , independent branch of water sciences.

During the 6th international Rainwater Catchment Systems Conference held in August, 1993, in Nairobi, Kenya, the International Rainwater Catchment Systems Association decided to hold its 7th International Conference in Beijing and suggested that we form the Local Organizing Committee to carry out the preparation for the Conference. It was my great pleasure to have this opportunity to promote the study of rainwater resources and its utilization.

Curing the past two years we have worked under the direction of the International Rainwater Catchment Systems Association and have made great progress. The Organizing Committee has received over 200 abstracts of papers and posters from 41 countries or regions, and about 130 full papers from more than 30 countries or regions. These papers concern each aspect of rainwater utilization, including comprehensive research, social and economical development, full utilization of rainwater for all the sectors such as urban, industry and agriculture, effects on ecology and environment, exploring the role of women in rainwater utilization, techniques of rainwater collection, water quality and its protection, study methodology and modelling. These abstracts and full papers are bound separately into three volumes with a total of more than 1400 pages, reaching an unprecedented scale.

The substantial support far the preparation work on this conference has come from the various organizations and academic institutions both at home and abroad. Thus, on behalf of the Local organizing Committee, I heartily wish to thank all sponsors, co-sponsors and the staffs working on the conference. We will make further efforts to edit and to publish the proceedings formally after the Conference. We hope the achievements obtained from this conference will further the theory and practice of rainwater utilization both in China and in the world