Monitoring water quality is critical to  human health, hence employing wireless sensor  networks for such a task requires a system that is  robust, secure and has a reliable communication.  Water borne diseases have become a major challenge  to human health. Around 400 million cases of such  diseases are reported annually, causing 6–12 million  deaths world-wide. Access to safe drinking water is  important as a health and development issue at  national, regional and local level. The population in  rural India mainly dependent on the ground water as  a source of drinking water. The main problems at the  time to effectively implement sensors are that, on one  hand, there is a lack of standards for contamination  testing in drinking water on the other hand, there are  poor links between available sensor technologies and  water quality regulations. In this paper the  application of WSN in environmental monitoring,  with particular emphasis on water quality. Various  WSN based water quality monitoring methods  suggested by other authors are studied and analyzed,  taking into account their coverage, energy and  security concerns.