Terrahydro - A distributed hydrological system using graph structure for unified water flow representation

This paper presents TerraHydro, a Distributed Hydrological System created to develop hydrographic basin water flow GIS applications. TerraHydro proposes a different computational representation for dealing with water flow in GIS applications. These applications involve the concept of local flow, extracted from terrain, which is the basis for most spatially explicit distributed hydrological models. Different computer structures based on regular grids, triangular irregular networks, contour lines, and irregular polygon tessellations have been used to extract local flow, occasioning entirely dependent on the data structure chosen for terrain representation. Then, each local flow set requires its own specific extraction algorithms, as well as different formats to store its associated local flow. TerraHydro proposes a data structure based on Graph Theory that unify computer local flow representation, independent of the data structures used for terrain representation permitting that a set of operations for water management can be formally defined over this new structure.