Optimization of an Existing Industrial Drainage System: Based on the results of a preliminary study an online monitoring network will be installed, operated, scientifically supervised and accompanied for the detection and monitoring of drained micro plastic loads. Besides a hydrodynamic simulation model of the entire pure-water-drainage system will be built up and calibrated and validated. Both systems serve for the optimization of an existing industrial drainage system to reduce the emitted micro plastic loads into the receiving water.