The study is a part of the implementation procedure of the Kołbiel bypasses – the S-17 expressway and the national road No. 50. The main goal of the investment (partially completed) is to avoid the built-up areas located in the vicinity of the routes. The main design determinants were: reducing noise nuisance and improving traffic safety, but also ensuring adequate capacity for the forecasted traffic volumes. The project was considered in a multivariate manner in combinations referring jointly to both roads in their mutual relation. The alternative plans of the routes were the subject of technical and traffic assessments (taking into account, among others, bridge structures, route drainage and investment staging), as well as environmental protection assessments and economic efficiency analysis. A multi-criteria comparative analysis of the alternative options of the road system allowed for the selection of the optimal solution, allowing at the same time any order of completion of the bypasses. The selected option was subject to successive stages of the implementation procedure, and the study was the sole basis for making an environmental decision.