Preliminary Estimation of Wastewater Treatment Plant Construction Costs Using Regression Analysis

Abstract

This study examined cost data for 130 wastewater treatment plant projects tendered by a public institution in Turkey between 2008 and 2022, and regression analysis was conducted to estimate the construction costs of these projects. Population projection, flow rate, aeration tank volume, sedimentation tank volume, and number of units are used as independent variables in the data set. The analysis determined that the independent variables had a significant impact on the total construction cost, and the developed model achieved an R² value of 0.763. The validity of the model was tested on three sample projects, and the accuracy rates between estimated and actual costs were determined to range from 92.56% to 97.58%. Therefore, the proposed model can be considered a suitable tool for preliminary feasibility assessments, early-stage planning, and approximate cost estimations. Nevertheless, it may not be sufficient as a standalone approach for detailed budgeting, tender preparation, or precise cost determination processes, where higher levels of accuracy are required, and should be supported by more comprehensive analytical methods.

Keywords

• Wastewater treatment plant
• Cost estimation
• Regression analysis (RA)

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