FIRST FLUSH EFFECTS IN AN URBAN CATCHMENT-AREA IN AALBORG

The paper describes the results of measurements from a 2 year period o n a 95 hectare urban catchment in Aalborg, Denmark. The results of the rain/discharge measurements include 160 storm events corresponding to an accumulated rain depth of totally 753 mm. The water quality measur ements include 15 events with time series of concentration of SS, COD, BOD, total nitrogen and total phosphorus. The quality parameters show ed significant first flush effects. The paper discusses whether either the event average concentration or the accumulated event mass is the most appropriate way to characterize the quality of the outflow. (C) 1 998 IAWQ. Published by Elsevier Science Ltd.