Journey of pathogen-loaded macroplastics in a mountain river channel – experimental data

This dataset provides experimental data on macroplastic transport and deposition in a gravel-bed mountain river under controlled field tracer experiments conducted in the Białka River (Poland). The dataset includes hydraulic parameters (discharge, flow depth, flow velocity, Reynolds number, Froude number), macroplastic transport outcomes (passed, failed), raw travel-time observations, deposition distances, spatial deposition patterns across channel sections, and litter mapping results under multiple discharge conditions. Additionally, the dataset contains qualitative microbiological detection (presence/absence) of selected bacterial taxa (Enterococcus, Escherichia coli, Staphylococcus spp., Staphylococcus aureus, Klebsiella spp., Pseudomonas spp.) in biofilms collected from plastic materials and control substrates, together with in-situ physicochemical water parameters (temperature, electrical conductivity, pH, dissolved oxygen). The data support quantitative analysis of riverine macroplastic transport processes, deposition mechanisms, hydrodynamic controls, and pathogen occurrence in mountain river systems. All variables are reported in SI units and structured in a relational multi-sheet Excel format suitable for statistical and probabilistic modeling. The data are made available under the principles of Open Access and are licensed under the CC BY 4.0.