A study on the Evaluation of the Hydrologic Benefit for Yuanshanzih Flood-Diversion in Keelung River Basin
| Autor: | Chin-Wei Chuang, 莊智瑋 |
|---|---|
| Rok vydání: | 2006 |
| Druh dokumentu: | 學位論文 ; thesis |
| Popis: | 93 The Keelung river basin is situated in northern Taiwan and lies immediately upstream of the Taipei metropolitan area. Frequent flooding occurs each year during the period from mid summer to early fall. The Hsichih area located in the lower basin has been hit hard quite frequently. Flooding resulted from typhoon storms, in particular, causes serious human casualties and property losses. In order to protect people's life and property, it is necessary to establish detention facilities especially the Yuang-shan-zih flood-diversion project. Popular hydrologic software can be used to understand the flood-diversion benefit for the Yuang-shan-zih flood-diversion. The Nanhu Bridge was designated as the outlet to establish rainfall-runoff model in Keelung river basin. The correction coefficient (, ) and the revised recession curve（ ） were calculate from observed data. Each river section can be simulated and predicted runoff hydrograph in this study. The benefit of Yuang-shan-zih flood-diversion can be estimated in HEC-RAS by the hydrograph simulation. In the developed model, it obtained a good simulation in the Jieshou watershed. Because the vegetation is covered well and developed less. However, the result is indeterminate in the Wudu watershed. There are numerous factors may influence runoff hydrograph. From the Jieshou watershed simulation results, the is negatively related to rainfall intensity（ ） and is positively related to peak flow（ ）. The regression equations are and. In Wudu watershed, the is negatively related to rainfall intensity（ ） and is positively related to peak flow（ ）. The regression equations are and. In the research, it must be modified in lower discharge. The threshold of peak flow reached 391 cms. In the model verification, it underestimated in the Jieshou watershed. It might be caused by sediment transport. The Wudu watershed is influenced by landuse and hillslope. The correlation and interaction among model factors is indeterminated. The result is less than Jieshou watershed. From the result between two watershed, the and have relations with characters of watershed and landuse. The flood-diversion benefit in the Yuang-shan-zih flood-diversion can use modified data in Jieshou watershed to estimate discharge for each hour. The water stage can be derived by peak flow in the HEC-RAS. The result shows watermark lower than embankment. So the Yuang-shan-zih flood-diversion can provide a good protection for people's life and property in midstream and downstream of Keelung River. |
| Databáze: | Networked Digital Library of Theses & Dissertations |
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