Criteria and guidelines of appropriate technology for river bank erosion control case study : Chaophraya river, Nakhonsawan province

Abstract

The objectives of this study were to find tile criteria and guidelines of appropriate technology for river bank erosion control using a case study of the Chaophraya River , Nakhonsawan province. The study chose 4 sites at the bend of the river and 4 methods of building protecting dams for the river banks. These were the riplab method ,the gabion method , the sheet pile method and the multiple sheet pile method. The study also took into consideration the safety rate for the slope of the river bank , the appropriateness of the location for the construction of protecting dams and the mean annual water level during the past 10 year period. A cross section of the river at the sites was studied to determine the speed of water passing through the spots of study and the cost to build the dams. This study used information obtained from the field survey and information already acquired from several government agencies to work out coordination , methods and guidelines for the project. The results of the study showed that similar results were obtained from the 4 sites. Taking into consideration the 4 methods of building dams , the riplab method and the gabion method are the two suitable methods as far as the operating area is concerned. However, when cost is taker into consideration , the riplab method is 18 % cheaper than the gabion method. Therefore the most suitable method of building protecting dams on the 4 study sites is the riplab method.