Open AccessThe effect of diameter and distance between vegetation in the riverbank to flood discharge by Eco-hydraulic in the Lawe Alas River, Southeast Aceh, Indonesia
Author(s) -
Ziana,
Maimun Rizalihadi,
Azmeri Azmeri,
A Nugraha
Publication year - 2020
Publication title -
iop conference series. materials science and engineering
Language(s) - English
Resource type - Journals
eISSN - 1757-899X
pISSN - 1757-8981
DOI - 10.1088/1757-899x/933/1/012051
Subject(s) - vegetation (pathology) , hydrology (agriculture) , flooding (psychology) , environmental science , flood myth , flow velocity , flow (mathematics) , geotechnical engineering , geology , geography , geometry , pathology , medicine , psychology , mathematics , archaeology , psychotherapist
One of the eco-hydraulic methods used to reduce flooding and erosion in rivers is by vegetation along the riverbanks. The main problem in the Lawe Alas River is repeated flooding in the downstream areas that need to be addressed upstream. The purpose of this study is to design the proper vegetation diameter and the distance between plants that can reduce the velocity and flow of the river. The method of study in this research consists of conducting field surveys, measuring river discharge, and calculating vegetation diameter on riverbanks to reduce velocity and discharge based on the equation proposed by Merten. The planned diameter of vegetation with diameter is 0,1 m - 1,1 m, and the distance between vegetation 1 m - 11 m. The results showed that the maximum discharge capacity of the Lawe Alas River was 514,360 m 3 /s. For the return period of 50 years, 50 m from the riverbank design, vegetation with a diameter of 10 cm to 110 cm can reduce flooding in the resulting discharge 222,95 m 3 /s - 241,68 m 3 /s. Discharge is greater than 50 yearly flood discharge, which is 528,670 m 3 /s. In conditions without vegetation (diameter = 0) velocity = 1,725 m/s, the velocity produced by the design is 0,727 m/s - 0,789 m/s. Discharge and velocity are reduced by 54% - 58% so that the vegetation diameter of 10 cm is suitable for environmentally friendly designs on the riverbanks 50 m. In conclusion, all planned vegetation diameters can reduce discharge and velocity. Recommended vegetation is local vegetation, which is a tree that produces fruit that can be benefited to the community so that it can be planted and managed by local residents.