Abstract
In Turkey, an average of 450 sewer line tenders are made annually and the total line length of these works is approximately 11000000 m. It is very important for both the investor and the contractor to know the costs of the sewer networks with such a large business volume. In this study, models are developed for early estimation of sewage line costs by the regression analysis method. Data belonging to 182 sewer line projects were used in the development of the models. Data on pipe diameter, line length, excavation depth, manhole amount, excavation amount, filling amount, filling type, shoring type, excavation class and real cost parameters were determined through the projects. Correlations between the determined parameters were specified and the parameters suitable for regression analysis were selected. As a result; among the developed estimation models, the equation using all selected parameters with a correlation coefficient of R² = 0.911 gave the most successful result.