流域中上游之都市化效應與分洪設施對下游流量推估之影響

The Impacts of Urbanization and Flood Diversion on Upstream Area for Estimating Discharge on Downstream Watershed

潘宗毅(Tsung-Yi Pan) ； 謝龍生(Lung-Sheng Hsieh) ； 鄭士仁(Shin-Jen Cheng)

《農業工程學報》 52卷1期 (2006/03) Pp. 56-74

https://doi.org/10.29974/JTAE.200603.0006

摘要

本文係探討基隆河流域因都市化效應及員山子分洪設施完工後對下游逕流量之影響。基隆河沿岸由於大多屬於未設站集水區，缺乏水文規劃設計。因此，本研究以半分布並聯型線性水庫降雨－逕流模式，配合分洪設施操作規則，設計適切之境況模擬。後以Nash概念模式調整受都市化效應影響後之合理流量。最後以洪峰流量與洪峰到達時間評估模擬結果。
研究結果可知由於員山子分洪設施功能之發揮，其下游之流量獲得適當之控制。可知分洪設施對基隆河中下游地區之洪災消減效果具有明顯改善程度。但隨著各核胞之集流產生對下游側流量之補注，員山子分洪設施為下游帶來之減洪效應越往下游其影響越小。

關鍵字

都市化效應 ； 分洪設施 ； Nash概念模式 ； 半分布並聯型線性水庫降雨－逕流模式

並列摘要

This study is to investigate the effects of urbanization and Yuanshantze flood diversion project on the downstream of Keelung River. However, most sub-catchments along Keelung River are ungauged watershed without any hydrological analysis. Therefore, a semi-distributed parallel-type linear reservoir rainfall-runoff model is introduced to carry out the simulation of runoffs. The simulations of scenarios are designed based on the operational rules for flood diversion project. Then, a Nash model is used to modify the discharge that is affected by urbanization. Finally, the simulations are evaluated by the discharge of the peak and its time of arrival.
When the return period is high, the analytical results show that the increases of floods to downstream are slight due to Yuanshantze flood diversion. Therefore, the study demonstrates that the project obviously improves the flood mitigation effect on downstream of Keelung River. Furthermore, the flood mitigation effect is decrease from Yuanshantze flood diversion to its downstream.

並列關鍵字

Urbanization ； Flood diversion ； Nash model ； Semi-distributed parallel-type linear reservoir rainfall-runoff model