Spatial assessment of monitoring network in coastal waters: a case study of Kuwait Bay.

Spatial analyses of water-quality-monitoring networks in coastal waters are important because pollution sources vary temporally and spatially. This study was conducted to evaluate the spatial distribution of the water-quality-monitoring network of Kuwait Bay using both geostatistical and multivariate techniques. Three years of monthly data collected from six existing monitoring stations covering Kuwait Bay between 2009 and 2011 were employed in conjunction with data collected from 20 field sampling sites. Field sampling locations were selected based on a stratified random sampling scheme oriented by an existing classification map of Kuwait Bay. Two water quality datasets obtained from different networks were compared by cluster analysis applied to the Water Quality Index (WQI) and other water quality parameters, after which the Kriging method was used to generate distribution maps of water quality for spatial assessment. Cluster analysis showed that the current monitoring network does not represent water quality patterns in Kuwait Bay. Specifically, the distribution maps revealed that the existing monitoring network is inadequate for heavily polluted areas such as Sulaibikhat Bay and the northern portion of Kuwait Bay. Accordingly, the monitoring system in Kuwait Bay must be revised or redesigned. The geostatistical approach and cluster analysis employed in this study will be useful for evaluating future proposed modifications to the monitoring stations network in Kuwait Bay.