The overall aim was to answer the questions: 1. Which pollutants are present in European stormwater and at which concentration levels? and 2. Are there major differences between mixed stormwater and local stormwater sources? The last question is especially important as most previous stormwater studies have analyzed mixed urban stormwater collected from large areas, but the stormwater to be handled in nature-based solutions (NBS) is often of very local origin such as in street rain beds and infiltration ponds in residential areas. Stormwater was sampled from stations at five sites across Europe: Odense (Denmark), Copenhagen (Denmark), Santander (Spain), Pontedera (Italy), and Ljubljana (Slovenia). For consistent sampling by different project partners and external partners, it was necessary first to develop protocols for stormwater sampling and station characterization and to provide standardized ready-to-use sampling- and shipping kits. Methods were developed for quantification of microbial antibiotic resistance, and quantification- and suspect screening for pollutants of emerging concern in source stormwater. The analytical results for water characterization and pollutants are available as an inventory data file (excel-file).