UNIVERSm SAINS MALAYSIA
Laporan Akhir Projek Penyelidikan Jangka Pendek
Water Quality Modeling For Integrated River Basin Management In Sungai Raja,
Kedah
by
Mr. Zorkeflee Abu Hasan Prof. Aminuddin Ab. Ghani
Dr. H. Md Azamathulla
Mr. Khairul Rahmah Ayub Mr. Leow Cheng Siang
2013
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12 Nov 12 @ 04:20 pm to 13 Nov 12 @ 08:00 am
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28 Feb 13 @ 03:45 pm to 01 Mar 13 @ 06:00am
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igure 3.18: Observed Stage-Hydrograph of Sungai Raja upstream of Pump Station taken 28 Feb 13 @ 03:45 pm to 01 Mar 13 @ 06:00am
3.6 DATA PREPARATION FOR MODELLING
Data preparation involved various stages and steps. Figure 3.19 shows the flowchart of simplified models preparation in GIS environment.
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simulation result for dispersions rate show very small variances and influenced coefficient of
determination value. The best fits value of coefficient of determination examined was 0.461
for dispersion rate of 19.390.
5.2,6 Water Quality Simulations
Model simulation for humid or wet weather condition have shown that better quality of DO and AN compared with dry season. DO concentration increases after rainfall is from 60% to 80% better than the concentration during the dry season. Increasing volume of water in the river can decreased AN concentration from 15 mg/L to 0.1 mg/L. Thus, the presence of rainfall in the catchment area can help improve the water quality of the river system.
Conservation methods studied further by flowing water containing high dissolved oxygen content in certain areas. Dissolved Oxygen concentrations in the Class 1 passes from upstream of Sungai Derga and Alor Siam. Significant changes of DO shown before approaching the junction of the three rivers. After the junction of these rivers, the water quality back to the original pattem which is in Class IV. This proves that the DO concentration in the Sungai Raja not affected by the concentration in the Sungai Derga and Alor Siam. Therefore, rehabilitation methods need to develop to ensure the success of the conservation program.
The next method of conservation is to increase the velocity of water to the river system. With the increasing speed by 40% of water has helped increase the DO level up to 75% of the original condition. However, concentrations of AN and pH is not changed according to water velocity, and this proves that the water velocity does not influence the concentrations of AN andpH.
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