Ažuriranje službenih podataka u Republici Hrvatskoj

The need for high-quality spatial information offering to the potential users of spatial data a simpler and more efficient use of the information is growing at the global level. According to the Law on State Survey and Real Property Cadastre (Official Gazette 16/07) and the Rules and Regulations on Topographic Survey and State Maps Production (Official Gazette 108/08), the State Geodetic Administration (SGA) is responsible for planning and implementing the topographic survey programs, development and maintenance of the topographic and cartographic database and official State maps and supervision and control of their production in specific stages of operations. By completing the Base Topographic Database (BTD) as the main originator of all official topographic datasets, products and topographic map in the scale of 1:25, 000 (TK25), the SGA is faced with the task of establishing an efficient system of updating. The data contained in the BTD is the topologically processed original data of the photogrammetric restitution, and represents the most accurate and detailed data created during the production of the topographic map in the scale of 1:25, 000 (TK25). Therefore, the SGA initiated a project in 2009 that resulted in the production of the BTD Updating Specifications and the development of updated TK25 sheets. These Specifications define the guidelines for maintaining the BTD and producing the updated TK25 editions in a manner that can satisfy the user needs for up-to-date data. The base datasets updating cycle amounts to 4 years but also defines shorter deadlines for updating certain data categories. The term “data categories” denotes the packages and classes included in the BTD structure and objects contained in TK25. The updating criteria for each specific class of data have been defined in such a way as to list the data of specific importance for the users under the first criteria group. In the Specifications, this means that deadlines have been defined for each specific class and that the content must be updated within these deadlines if there are any changes in the reality for certain data categories. By using this methodology of the base SGA datasets updating process organization, we have been able to respond to the following three basic questions: what, when and where to update i.e. grounds have been laid for the important changes to the objects to be collected immediately after their creation while, at the same time, preserving the real cartographic value of the entire dataset.