GIS TECHNOLOGY IN WATER AVAILABILITY USING ARCHYDRO DATA MODEL

We proposed to show the methodology in using The ArcHydro data model as the data repository to calculate the surface water amount in a basin. The Arc Hydro Data Model is considered as a geographic database containing a GIS representation of a Hydrological Information System under a case-specific database design. It includes a set of tools providing raster, vector, and time series functionality like rain, temperature, evaporation, uses of water. The estimation of the available surface water is based on the Official Mexican Norm NOM-011-CNA-2000, “Water resource conservation” (Conagua 2005), that uses the continuity equation. INTRODUC TION Knowing the water quality and quantity available in a certain area is essential for assigning this vital liquid to the existing and new stakeholders; this task becomes difficult when information about quality and quantity is scarce or null. Water resources managers need to have accurate data to take decisions and also need tools that help them know the water availability in an easier and accurate way. Time series and additional data required to estimate surface water availability are extensive, therefore it is complex to store, organize and handle that information within a logical and flexible da ta structure. The ArcHydro data model allows implementing a database with a standard and flexible structure to store all the data related to water resources. This database is a useful tool since it provides the necessary data for estimating water availability, stores the results obtained and makes easy to query and display data within a geographic information system (GIS). OB JECTIVE The objectives established in this work were: developing a software tool to estimate surface water availability, implementing a database using the ArcHydro structure to store the results and all the information required for computing the water availability and using the developed software tool to estimate the water availability in a Mexican watershed.