More than 90% of the watercourses in Germany that have been assessed by authorities are in poor ecological status (Federal Environment Agency, 2022). At the same time, there is a lack of reliable data on the condition and pollutant levels of small watercourses—that is, streams with catchment areas of less than 10 km²—since these are not adequately accounted for in monitoring under the European Water Framework Directive (EC-WFD, 2000).
FLOW is a nationwide citizen science project for the ecological monitoring of watercourses (www.flow-projekt.de). In this project, citizen scientists from schools, environmental and fishing clubs, and other groups investigate the condition of small streams that are not covered—or are only inadequately covered—by official monitoring. Our goal is to support aquatic research while simultaneously raising public awareness of the importance of—and threats to—our watercourses. Since 2021, approximately 200 groups with a total of about 2,000 participants have been involved in the FLOW project. So far, citizen scientists across Germany have examined approximately 500 stream sections by assessing the stream structure, measuring the chemical and physical water quality, and identifying the community of invertebrates on the stream bed (macrozoobenthos). The scientifically verified FLOW data show that the majority of the agricultural streams studied are in poor ecological condition.