In addition to failure in monitoring water quality in the study area, the monitoring networks are not designed based on standard guidelines; moreover, there is no ongoing assessment of these networks. The great or small number of sites in the monitoring networks will cause problems. This paper aims to evaluate the monitoring networks of the changes in groundwater quality of the Shib-Kuh aquifer established in 2005 in South West of Iran. The aim of this study is to improve the monitoring networks and save expenses. In this aquifer, the groundwater main chemical anions, cations, EC, TDS, TH, SAR and pH are measured in 20 sites. The statistical cluster analysis methods are used and observations, variables and sampling sites are analyzed and evaluated. The results showed the probability of about 25 percent reduction in the sites. It also proved that it was possible for some of the measuring parameters to have been removed. Cluster analysis method is a suitable way to evaluate the quality of establishment as well as the function of the monitoring networks of water resources. Through the application of this method, the number of sites, variables, or both of these factors can be optimized and this optimization leads to upgrading of monitoring networks.
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