A conceptual framework to evaluate the outcomes and impacts of water safety plans.

A Water Safety Plan (WSP) is a preventive, risk management approach to ensure drinking water safety. The World Health Organization (WHO) guidelines place WSPs within a larger 'framework for safe drinking-water' that links WSPs to health, creating an implicit expectation that implementation of WSPs will safeguard health in areas with acceptable drinking water quality. However, many intervening factors can come between implementation of an individual WSP and ultimate health outcomes. Evaluating the impacts of a WSP, therefore, requires a much broader analysis than simply looking at health improvements. Until recently, little guidance for the monitoring and evaluation of WSPs existed. Drawing examples from existing WSPs in various regions, this paper outlines a conceptual framework for conducting an overall evaluation of the various outcomes and impacts of a WSP. This framework can provide a common basis for implementers to objectively monitor and evaluate the range of outcomes and impacts from WSPs, as well as a common understanding of the time frames within which those results may occur. As implementers understand the various outcomes and impacts of WSPs beyond health, a strong evidence base for the effectiveness of WSPs will develop, further enabling the scaling up of WSP implementation and provision of better quality water.