圖書典藏及影音數位平台

後龍溪下游段(福基至河口)治理基本計畫於民國71年奉 經濟部核定民國72年省府公告，上游段(社寮角橋頭至福基)於民國81年辦理河川治理規劃，並於民國85年奉 經濟部核定，民國86年省府公告治理基本計畫，水利規劃試驗所於民國96年完成『後龍溪治理規劃檢討』。而支流打馬溝溪迄今並未有相關治理規劃。後龍溪流本流民國70年公告迄今已歷時35載，期間歷經民國88年921大地震及數次颱洪，河道地形及周邊環境均有變化，為配合河道地形環境變化及社會發展需求，故辦理後龍溪水系治理規劃檢討，

The Houlong water system improvement plan report completed in 1986~2016, it has been more than 20 years. river map identificatication is inconsistent with the status of the terrain, caused river harnessing and management disputes caused events. Furthermore, taking into account climate change, extreme rainfall events and flow changes caused by the potential risks, Improvement of damage and shall be incorporated into a regular section, review of comprehensive harness idea to hand, to facilitate follow-up of river management and governance. Therefore, the River Management Office deems it necessary to review the Houlong water system of overall planning of the necessary. Basis for subsequent project application, expected to protect people’s lives and property safety goals of sustainable use and river.The Houlong River basin is located in Miaoli County. The north of basin is Zhonggang River basin. The south of basin is Xihu River basin. The east is Central Mountain Range. The Houlong River originated in Central Mountain Range, and flows into the Taiwan Strait. The length of the mainstream is 58.5 km, and Watercourse average slope is 1/160. The area of the basin is 536.6 km2.This project includes The Houlong River mainstream and 13 branches. According to the peak flow analysis, all of them followed up the original plan in 1986~2016. The protect standard of Houlong River and Laotianliao River is 100 recurrence return period, and the other 12 main branches in left bank are 25 recurrence return period. The levee elevation of Houlongn River mainstream is planned flood level plus 1.5m. Laotianliao River, Xindian River, Shahexi River, J?long River, Wenshui River, Nanhu River and Dahu River are planned flood level plus 1.0m. The other are planned flood level plus 0.8m.According to the basic data collection, site survey & questionnaire and hydrological analysis review, the basic principles of governance are maintenance of the natural landscape, environmental creation, reduction construction, the space reserved for climate change.According to the works by this project, the total cost is N.T 137.67 million dollars. The works cost of Houlong River is N.T 69.08 million dollars. The works cost of LaotianLiao River is N.T 7.82 million dollars. The cost of Xindian River is N.T 1.55 million dollars. The works cost of Shahe River is N.T 15.93 million dollars. The works cost of Damagou River is N.T 15.57 million dollars. The ratio of benefit to cost is 0.13.