Water Quality Index Score in River Water Treatment Plant at Upper Klang and Gombak River Catchment

Abstract

National River Water Plants are located along upper Klang and Gombak river catchment to purify the polluted river using direct contact methods. As the current water quality situation in the study area is poor due to the contribution of anthropogenic activities on the water quality degradation in these urban rivers, the investigation was performed using the Water Quality Index. This paper gives the overall performance of RWTP using Water Quality Index (WQI) calculation methods. The WQI act as the basis of environment assessment towards to river water quality classification under Malaysia National Water Quality Standards. As an overall result, 57 percent from the total effluents achieve target Class II and above and another 43 percent achieve Class III and below regardless of two (2) RWTPs are under target from the average monitoring; RWTP Sg Gisir and RWTP Sg Sentul. However, the result for RWTP Sg Sentul is not yet conclusive since the monitoring duration is less than 2 years. Certainly, RWTP Sg Gisir needs to be taken into consideration for more frequent maintenance of the RWTP or upgrading of the RWTP oxidation tank as suggested in several MBBR/IFAS operation. As to improve the RWTP performance to score higher WQI, the introduction of recycling sludge in the biological tank so it will be a shorter reaction time. Additionally, the RWTP owner should implement a frequent maintenance work into RWTP component especially clarifier, sludge collector, biological oxidation tank and rubbish trap collector.