GIS Water Resource Case Studies Analysis

As natural resource managers—biologists, botanists, ecologists, environmental regulators, hydrologists, planners, petroleum engineers, foresters, and farmers— rely on the analytical power of GIS for help in making critical decisions and manage the earth's resources. I would like to know your experiences and case studies where GIS is used for natural resource management. Here is one case study where GIS is used for "Mapping and Managing Potable Water Infrastructure Assets " http://www.esri.com/news/arcnews/winter0809articles/mapping-and-managing.html