Feasibility of Using Topographic Data by TOPODATA Image in Urban Drainage Projects

In general, the urbanization process in cities increases the impermeabilization of the soil, increasing surface runoff, leading the population to suffer from risks of flooding. In this context, the design of the drainage system is fundamental, which depends on the terrain characteristics. The total station is one of the most used equipment in topographic survey in field service. With the technological advance, it is possible to obtain this information remotely, as through satellite image with the aid of geoprocessing software. Thus, the objective of this research was to carry out a feasibility study on the use of topographic data obtained by TOPODATA Project images generated by Instituto Nacional de Pesquisas Espaciais - INPE in an urban drainage project. The seat of the municipality of Ipixuna do Pará was adopted as study area, where altimetry information was obtained by total station and by TOPODATA images. The interpolation kriging method was used to generate the contour lines and the Digital Terrain Model (DTM). To evaluate the performance of the TOPODATA data, the Pearson correlation coefficient test (R) and the Root Mean Square Error (RMSE) were used. For the microdrainage project, an area of approximately 14 hectares was delimited within the municipality's seat. From the statistical analysis, satisfactory results were obtained with R of 0.81, a “very high” correlation; and the RMSE of 1.27 m in the project area. Therefore, it was verified that it is feasible to use the TOPODATA image in the altimetry survey for areas considered small, with good correlation, considering the agility in obtaining the data, allowing access to information in places of difficult access, in addition to the economic aspect.