A study on the establishment of the floodgate classification in Miaoli and Hsinchu areas

• Main Authors: Chih-Shang Wan, 萬志上
• Other Authors: 詹勳全
• Format: Others
• Language: zh-TW
• Published: 2014
• Online Access: http://ndltd.ncl.edu.tw/handle/6p228k

碩士 === 國立中興大學 === 土木工程學系所 === 102 === Taiwan due to its subtropical climate and geographical environment, the rainfall is abundant and concentrates in summer and autumn which causes flooding in the rainy season. The social change and economic development results in demand of marginal land in recent years. To avoid the typhoons or heavy rain leading to a flood, it is necessary to build embankments, floodgate, and pumping station to reduce the flood potential. The floodgate is frequently used to avoid the outland water flowing backward during flooding periods. If the floodgate is not working properly, it is easy to cause the flooding in the lowland area and the loss of life and property. To management the floodgate, it is necessary to establish the classification of the floodgate. About 301 floodgates in the Hsinchu tidal river, Miaoli tidal river, Houlong River, Jhonggang River, Ke-ya-Chi Drainage, and Yan-gang-si Drainage are the study areas in this study. The economic and population factors near the floodgate, the surrounding conditions and the floodgate facilities were selected to evaluate the floodgates impact on the residents. A high degree of vigilance floodgates are 10 doors, moderate alert floodgates 44 doors, and low level floodgates are 247 doors. The floodgates on the moderate and high alert situations are mostly the drainage is not very good, and the sediment deposition around the floodgates are moderate to severe. In addition, the higher maintenance frequency of the floodgates and the outside water level is higher than inside water level. The damage to the base of the floodgates or the dikes may cause the leaking water during the typhoons or the heavy rainfall. According to the results in this study, improve the drainage facilities, discuss the water level difference, and the field investigations on the floodgates are proposed. The reasons for sediment deposition around the floodgate are expected to provide feasible advices and designs for preventing sediment deposition in future planning.