The document provides an overview of the HYDROSYS project and its applications. The project aims to enable on-site data collection and visualization to support new ways of observing environmental processes. It provides an infrastructure for teams to monitor events and analyze natural resources using handheld devices and potentially UAVs. This improves monitoring for environmental scientists through integrating handhelds, sensor networks, and modeling. The document also describes applying the GEOtop modeling system to simulate rainfall-runoff for the instrumented La Fouly watershed in Switzerland, using available meteorological, soil, and water level data.