Digital watershed representation within the NewAge-JGrass system

Abstract

This paper describes the theoretical and technical architecture of a digital watershed model (DWM) that can be used as a basis for storing data relative to a river basin and to run a spatially distributed hydrological model that is directly representable in a GIS (such as uDig). The DWM deployment is based on the integration of geospatial modelling libraries (the Geotools) by means of which geographical information is encoded and becomes an integral part of the modelling process. Subsequently, the paper identifies a sequence of operations that have to be performed in order to obtain the desired DWM, and briefy describes the necessary programs. For the topological ordering of the network, a generalisation of the Pfafstetter ordering scheme is presented as well as a partitioning scheme based on the distances to the divides (namely Hack’s Lengths). These programs are stand-alone components which can be run in different ways by using: the uDig Spatial Toolbox interface, the user friendly Object Modelling System (OMS) console or by command line. The OMS console completes the work by allowing the connection of all parts to produce well-designed modelling solutions in which the components are connected and executed together. The tools presented have been applied to the Little Washita river basin (Oklahoma, US) and to the Piave river basin (Veneto, Italy).