The program RS153 is used to determine the water pollution and allows all tasks of the guideline DWA M 153 "Recommendations for handling rainwater" to be completely processed. With RS153 the rain drains from paved areas are evaluated - taking into account the influences of air, water and runoff areas. In order to meet the requirements of the guideline regarding water pollution, it may be necessary to take measures to reduce pollution. In regards to Appendix 2 DWA-M 153, RS153 documents the necessity of the treatment measures and defines their scope.