Polders in Asia : Bangladesh, China, Indonesia, Malaysia, Philippines, Thailand, Viet Nam

Abstract

The construction of polders was recognized as a potential method of developing coastal lowlands, river valleys, marshes and swamp ground, as well as tidal embayments and gulf areas. In as much as the largest populations in Asia are located in coastal areas it was agreed by ESCAP that the application of polder technology would be of value to many ESCAP member states in need of new land in areas which were at present flooded or partially flooded because of poor drainage. ESCAP countries noted that there was a need to provide a forum for exchange of experience and information relevant to polders. Consequently, the Government of the Netherlands agreed to share its well known expertise in this field with developing countries of Asia. A study tour of polderised areas of the Netherlands in November of 1989 was arranged by ESCAP in cooperation with the Geological Survey of the Netherlands, the International Institute of Hydrological and Environmental Engineering (IHE), the Flevoland Directorate, and an expert from South Holland Province. At the conclusion of the study tour a number of papers were presented by ESCAP participants. Those papers are presented herein for the use of developing countries in Asia which may wish to review the progress made in the development of polders in seven countries of the region, i.e. Bangladesh, China, Indonesia, Malaysia, Philippines, Thailand and Viet Nam. In a number of these countries the use of dyke systems and the application of polder technology has resulted in the drainage of areas which normally would have been inundated by sea water. In other areas coastal embankments have been important in mitigating the impact of flooding as well as in enabling new land to be brought into agricultural production. Thousands of square kilometres of land have been reclaimed in Asia as a result of the proper application of the polder concept. It is now recognized that polder technology, if properly applied, can result in an improvement in the development of coastal lowlands resulting in new rice lands, fish culture, salt culture and other innovative economic activities such as cultured pearls, crocodile farming, production of sea foods, and so on. Especially notable progress has been made in a number of ESCAP countries as indicated by the papers presented in this volume which is one of a series devoted to the application of geology to development problems.