Water Quality Index for Water Distribution System

Abstract

Good water distribution systems should provide good quality water with enough pressure for customers. For controlling water quality, chlorine is one of the most used chemicals. This research analyzed two water quality indices from free residual chlorine concentration in the system that are a modified Canadian water quality index (MCWQI) and a safety water quality index (SWQI) in a district metering area (DMA) of Metropolitan Waterworks Authority.

The results showed that the SWQI is 69.30 meaning the DMA can be considered as safe. The MCWQI is 93.98 which means the DMA water quality is excellent. However, the MCWQI value did not indicate whether the problem was from low or high free residual chlorine concentration in the network. When the MCWQI was hourly calculated, we found that the hourly MCWQI are varied resulting in water quality condition ranging from fair to excellent. Therefore, hourly MCWQI analysis can be used for a better water quality management.