Sewage systems investment and operational costs in Poland and Europe in 1950-2024

This paper presents a historical and contemporary analysis of investment and operational costs associated with sewer networks in Poland and selected European countries from 1950 to 2024. The primary aim of the study is to identify long-term trends and cost dynamics resulting from changing legal frameworks, technological advancements, environmental standards, and urban development pressures. The hypothesis assumes that the costs of sewer infrastructure are not linear over time and are significantly influenced by external regulatory and economic drivers. The methodological approach combines historical data analysis with the use of descriptive statistics and time series models, based on data from national and EU statistics, technical archives, and financial reports. The results indicate several distinct cost phases: post-war reconstruction, expansion during industrialisation, stagnation in the 1990s, and sharp increases after EU accession and implementation of the Urban Waste Water Treatment Directive. The study concludes with a comparative overview of the cost profiles in different European regions, showing convergence of expenditures after 2004. These findings may support future investment planning and policy-making in sewer infrastructure.