Floodway design affected by land use changes in an urbanized area

Journal of Water and Land Development

article

Agus Suharyanto¹  Yatnanta P. Devia¹  Indradi Wijatmiko¹ 

[1] Universitas Brawijaya, Faculty of Engineering, Civil Engineering Department

关键词: channel dimensions;    channel normalization;    floodway;    land cover changes;    land use;    runoff coefficient;   

DOI  :  10.24425/jwld.2021.137120

学科分类：农业科学（综合）

来源: Instytut Technologiczno-Przyrodniczego / Institute of Technology and Life Sciences

【 摘 要 】

A flood occurs for many reasons, such as excessive rainfall, runoff coefficient, or an insufficient river channel capacity. The discharge flowing through the floodway depends on the maximum main river dimension that can be normalized. LU/LC changes are affected by runoff discharge, and runoff discharge is affected by the floodway design. The study dis-cusses the effect of land use (LU) or land cover (LC) changes and the design of floodway channel dimensions in the Kali Kemuning watershed, East Java Province, Indonesia. The Nakayasu synthetic unit hydrograph has been used to analyse the runoff discharge, and the Hydrologic Engineering Center’s River Analysis System software analysed the hydraulic proper-ties of river and floodway channels. Results show that the floodway channel design is determined by LU/LC conditions, and the river channel is normalized toward its maximum dimensions. Normalized channel depths and widths vary from 4 to 7 m and 16 to 46 m, respectively. The floodway channel is rectangular, with a bottom width of 10 m and depth of 4.5 m. With the runoff coefficient equal to 0.75, these normalized channel and floodway dimensions are suitable for the flood up to the 100-year return period runoff discharge.

【 授权许可】

Unknown