Hydrospatial Approach to Assist Decision Making on Reservoir Protection Zones

Abstract

Protection zones established for stream drainage systems or water supply reservoirs serve as a major protection measure to reduce water contamination. In essence, a number of physical, chemical, and/or biological processes act together or separately in these areas to reduce a contaminant’s concentration or to convert it to a less threatening form. Yet, time is an important criterion for these processes to occur, as there is less potential for the concentration of a contaminant to be reduced when there is a shorter time of travel between the point where the contaminant enters the stream and the reservoir intake point. In this regard, this study employs the time component of flow among a set of spatial criteria that commonly target assessments of functionality and effectiveness for potential protection zones in a watershed. Such criteria could be practically evaluated in a multicriteria decision-making framework for a proper design of protection zones. The approach is expected to contribute to protection zone design with its increased practicality and similar use in common applications, which may not always be achieved from case-specific modeling exercises.