Validação de modelos digitais de elevação aplicados à sistemas de abastecimento de água: estudo de caso em Rio Negro – MS

Abstract

The design of an efficient water supply system relies on high-quality topographic data, which significantly impacts installation, operation, and maintenance costs. Traditionally, obtaining such data involves field surveys, resulting in considerable expenses. This study aimed to assess the feasibility of replacing field methods with free digital terrain models (DTMs), using the municipality of Rio Negro - MS as the study area. Initially, statistical analyses were performed to compare the SRTM, Copernicus, and FABDEM models, identifying which one presented the smallest differences compared to reference contour lines provided by the state’s sanitation company (Empresa de Saneamento de Mato Grosso do Sul - SANESUL). The most accurate DTM was applied to the hydraulic model of the study area’s water distribution network, also provided by Sanesul, to compare the pressure heads of the original and modified networks. The DTM with the lowest root mean square error (RMSE) was FABDEM (11,22 m), followed by Copernicus (11,24 m) and SRTM (11,47 m), with results also indicating a high average error due to possible inconsistencies in the reference contour lines. Applied to the hydraulic model, FABDEM predominantly presented variations between -2.00 and 3.00 mH2O at the nodes, showing no significant differences considering the system's operating pressure. In conclusion, the use of digital terrain models is feasible for water supply projects, although designers must exercise caution during the verification of results.