Assessment of pollution risk requires the assimilation of spatiotemporally
variable data on water quality parameters. This paper describes a
GIS user-interface program coupled with a water quality index (WQI) model
that was developed and built to assess water quality in the Sg. Buloh river
basin. Fifty-two water sampling stations were selected for this study, and the
WQI model considers parameters such as pH, dissolved oxygen, biochemical
oxygen demand, chemical oxygen demand, total suspended solids and
ammonia nitrogen, as used by the Department of Environment in Malaysia.
The spatial pattern of each parameter was analysed, and WQI values were
calculated, ranging from 4.48 to 76.8 on a scale with 100 representing the
highest pristine quality. A map of WQI is provided, which will help planners
and decision makers to develop water pollution control strategies, and the
model is capable of extension with further data to address pollution risk
