圖書典藏及影音數位平台

民國88年起至90年，行政院國家災害防救科技中心(前國家科學委員會防災國家型科技計畫辦公室)首次進行並完成全省22個縣市淹水潛勢圖分析與製作，供各級行政機關做為施政參考。近年來，由於圖資資訊化及淹水模擬分析程式快速演進，經濟部水利署於民國96年起進行全國淹水潛勢圖更新工作(第一次更新)。由於淹水潛勢圖製作所需之基本資料、模擬條件及演算模式不盡相同，無法整合及提高淹水潛勢圖之準確性，因此本所於102年辦理「全國淹水潛勢圖資更新及整合先期計畫」並依據目前淹水模擬技術，參酌國內外做法，並藉由專家座談會彙整意見，制訂「淹水潛勢圖製作及測試手冊(草案)」，俾利水利署暨所屬機關製作淹水潛勢圖時，有遵循標準作業程序，並產出穩定、可靠及高品質之成果，利於後續整合應用。因此，本計畫將以此手冊(草案)內容為基礎分行政轄區逐步完成更新，本計畫以「嘉義縣市」為範圍辦理淹水潛勢圖第二次更新計畫，作為中央部會及所轄各級政府再行審視各水災災害防救計畫之用。

This project was based on the "inundation potential map production", which were completed by ,Water Resources Planning Institute, Water Resources Agency, MOEA in "A Preliminary Plan for Updating and Integrating the Flood Potential Maps in Taiwan", in 2013. The objective of the project was producing the stable and reliable stable, reliable. In this project, the region of "Secondary Upgrading Potential Inundation Maps" was Chiayi County and Chiayi City. The project would provide Flood Potential Maps for the Government and be references to the government when revising the flood defense projects. This project was divided into three stages. The first stage was the basic data collection and feature analysis, including analysis region division, topographic analysis, hydrological analysis and oceanographic analysis, for the basis of the flooding simulating setting. The second stage was the flooding model establishing, test and verification. Using major typhoon or flood events within the last five years, the second stage tested the hydraulic routing, each parameters and hydraulic structures establishing of the flooding model so that the simulation results met the flooding areas of typhoon or flood investigation reports and the potential inundation maps of the third stage met the current status of Chiayi County and Chiayi City. The third stage was flooding scenario simulating and flood potential maps producing. In the third stage, the flooding model was modified in accordance with the completed regulation projects of Flood-prone Areas Planning Project included the flood ways and the regulation cross sections of the drainage systems until 2014 so that flood potential maps could prove the benefits of the regulation projects. Flooding scenario simulating had three different duration rainfall, respectively, 6 hours, 12 hours and 24 hours, nigh Quantitative rainfall and eight return period for corresponding to the flood potential maps. Then, the local symposium took place in order to checking the flood potential maps by the disaster prevention personnel of Chiayi County and Chiayi city government. According to the flooding potential simulation results, the main flooding areas of Chiayi County were coastal subsidence areas and part of river bank areas. Because the water height of the main rivers rose highly, the drainage could not be discharged into the main rivers by gravity and overflowed, such as Budai and Yijhu. Part of river bank areas, such as Dongshih, Liujiao, Xingang, Xikou and Taibao City, was overflowing because of high-intensity rainfall. As for the urban areas, Chiayi City, the main reason that were flooded was the volume of runoff over the design capacity of the stormwater sewer and overflowed from manhole in high-intensity rainfall of high return period.