Author(s): Md Mobassarul Hasan, Zalin Amir, Abdullah Al-Mamun
Linked Author(s): Md Mobassarul Hasan
Keywords: Hybrid-off river augmentation system (HORAS), numerical model, rainfall runoff, salinity intrusion, water availability.
Abstract: Hybrid-off river augmentation system (HORAS) is a water supply system where river water is harvested through ponds and pumped into the treatment plant for processing. HORAS has been adopted in this study to solve the increasing water crisis in the district of Kuala Langat in Selangor state as a big abandoned mining pond (commonly known as MC8 & MC9) is available along the river near the village Labohan Dagang. Three different models are used to carry out the study such as Hydrological, Hydrodynamic and salinity model. The Hydrological model is used to calculate the rainfall runoff from all the catchments in the Langat Basin. Whereas the Hydrodynamic model is used to calculate available water in the river by considering rainfall runoff from upstream, and tidal action from downstream and salinity model is used to assess the salinity level in the river under different hydrological conditions. Both the Hydrological and Hydrodynamic model have been simulated for 40 years from 1975 to 2014 to gather sufficient data for reliable statistical analysis. It is evident from the rainfall runoff calculation that 95% dependable flow near the ponds is about 8. 32 m3/s when there is no intervention at Dengkil whereas it is about 1. 09 m3/s when there is intervention at Dengkil (no flow from Dengkil). On the other hand, it is found from the Low Flow Analysis that if there is no flow from Dengkil, the proposed site will still receive about 2. 72 m3/s rainfall runoff in 50-Yr ARI drought event. It is also evident from the Hydrodynamic model result that the available average flow near proposed site is about 97. 95 m3/s due to tidal action which is free from salinity intrusion even in extreme drought condition. Therefore, HORAS will be a fruitful solution for the district of Kuala Langat during extreme and prolonged drought event
Year: 2017