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Electronic Navigational Charts are currently the most popular and fast developing digital hydrographic product. Officially, they are the only electronic charts which enable a legal change to paperless navigation. The process of ENC creation is time-consuming, which is largely due to data acquisition and edition. For ENC geodata to be useful they should meet several conditions. First of all each element must be charted with maintenance of proper requirements relative to situational and bathymetric accuracy. Apart from this, all geographic features must have necessary attributes, which are defined and described in valid standards. Additionally, data should be up-to-date and, in view of their number, ordered and easy in management. Realization of all the above conditions is possible by application proper software of GIS environment. The authors of this paper have used and verified in chart creation process ageodatabase, which is one of the basic products of the ESRI software. In its basic functionality a geodatabase enables creation of feature classes, their modification, loading of other data, creation of topology relation, creation of subtypes and attribute domains or control of correctness of new data. The geodatabase elaborated by the authors of this work consists of feature datasets and feature classes. Feature datasets corresponded to the structure of thematic categories, whereas feature classes corresponded to geographic objects which created navigational charts. All features were coded according to valid standards of electronic chart creation for inland shipping. The concern was mostly with compliance to proper geometry and predefined attributes. For limiting of data error, subtypes and attribute domains were predefined, which also improved data management and their modification and creation. In the last stage the geodatabase was assessed as a product used in the process of IENC production. The presented method of data elaboration shows the possibility of application of the GIS environment software and its basic functionality in IENC map creation. Data in this form can be compiled with the use of dedicated hydrographic software to obtain interoperable format based on S-57 standard. Practically, data compilation was done by the Hydrographic Office of the Polish Navy. This method of map production enabled to obtain the first in Poland inland electronic chart.
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