DEVELOPMENT OF HYDROLOGICAL INFORMATION SYSTEM FOR A MICRO CATCHMENT

Abstract

The concept of developing hydrological information systems was contemplated during the International Hydrological Decade (IHD) 1965-74 as the information systems are considered to be better tools for data storage, retrieval and processing. Geographical Information Systems (GIS) are relatively new and rapidly developing class of computer applications. Mostly the hydrological data are geo-referenced, and GIS assists in the preparation, analysis, display and management of geographical or geo-referenced data, the integration of hydrology and GIS is quite obvious. So, a Hydrological Information System (HIS) can be defined as a GIS based Information System, which can store, retrieve and analyse the hydrological data to carry out research as well as to solve many of the hydrological problems. This study presents the development of a hydrological information system based on structured and object-oriented design for a micro catchment. HIS contains three modules viz., GIS, Database, and Analysis. The GIS module is a tailor-made GIS to be developed to suit the hydrological modelling. The data and other information related to the catchment and catchment objects are stored in the Database module. Analysis module will assist in statistical analysis, stochastic analysis and 'hydrological modelling. To develop the hydrological information system for a micro catchment, Mallavaram micro catchment of Fast Godavari district, Andhra Pradesh has been considered. The GIS module is developed to the extent of digitising the catchment and it's objects. Different map layers- viz., geology, streams, habitations, wells, roads, tanks etc., are added to the GIS module. The database module has also been developed and the objects of the catchment are categorised into eight classes viz., Wells, Tanks, Streams, Hydrographic stations, HM stations, Networks, Land features and Habitations. Graphical user interface (GUI) has also been developed, to integrate the GIS and database modules and - display the object information on the