International Journal on Advanced Science, Engineering and Information Technology, Vol. 9 (2019) No. 4, pages: 1260-1268, DOI:10.18517/ijaseit.9.4.8934

Overcoming Flood in Batang-Takung Downstream Using Numerical Simulations

Mas Mera, Fakri Rantoso

Abstract

Batang-Takung River empties into Batang-Pangian River in Sijunjung Regency, West Sumatra Province. The downstream of Batang Takung is frequently flooding in the rainy seasons. The water-surface level at the intersection between Batang Takung and Batang Pangian is higher than that in the Batang-Takung downstream. This situation is then getting worse since the river bed of the Takung downstream is relatively flat. As a result, backwater phenomenon occurs along the Takung downstream and then it floods up to the surrounding residential and plantation areas. The present study is devoted to overcome the flood in the Batang-Takung downstream by numerical simulations using the existing software of HEC-RAS 4.10. In the present study, the software is applied to predicting the flow depths in both the uniform and varied flows and in the one-dimensional, steady-state condition for all simulation scenarios. In the first scenario, Batang Takung, Batang-Pangian Hulu (Batang-Pangian part from the intersection upward) and Batang-Pangian Hilir (Batang-Pangian part from the intersection downward) are in the existing condition. Similar to the first scenario but Batang-Pangian Hulu is put aside in the second scenario. The third scenario is the same as the first one but Batang Takung is put aside. The fourth scenario is the same as the first one but the upstream of Batang-Pangian Hilir around 1013 m long is straightened. In the fifth scenario, an additional intersection of Batang-Pangian Hulu and Batang-Pangian Hilir is made about 1762 m downward of the existing intersection. This is done by making a new trace in the downstream of Batang-Pangian Hulu. The simulation results show that straightening the river trace or normalizing the river is not effective in overcoming the flood in the Batang-Takung downstream. However, by making an additional intersection between the Batang-Pangian Hulu and the Batang-Pangian Hilir located about 1762 m downward, the flood in the Batang-Takung downstream could be solved.

Keywords:

flood; backwater; river intersection; meander; simulation.

Viewed: 78 times (since Sept 4, 2017)

cite this paper     download