Abstract
This study evaluates the spatio-seasonal patterns of river- and groundwater quality in the city of Jakarta, Indonesia, using the Nemerow-Sumitomo Water Pollution Index (WPI). The evaluation of water resources in Jakarta is very important because many residents still heavily depend on groundwater resources, which they extract by direct self-pumping; hence, continuous consumption of this water may introduce some health risks. The water quality is influenced by factors such as the seasons and the location relative to the pollution sources, so the quality may differ in time and space. To evaluate the water quality in the city, the Jakarta Environmental Management Board (BPLHD) conducted river- and groundwater sampling in July 2007 (dry season), November 2007 (early rainy season) and August 2008 (late dry season). During each season, 67 river water and 75 groundwater samples were collected from stations throughout the city, and approximately 32 biophysicochemical water parameters were measured at each station. The results show that the quality of both the river water and the groundwater was worse in the dry season and toward the northern region. This implies that the local residents should be aware of their consumption of groundwater in the northern region, especially during the dry season.
