SETTLEABLE SOLIDS FROM COMBINED SEWERS - SETTLING, STORMWATER TREATMENT, AND SEDIMENTATION-RATES IN RIVERS

Settleable solids are an important pathway for pollutants found in riv er sediments. To study settling behaviour of settleable solids, settli ng velocity was measured by a settling apparatus. Special measurements were undertaken to determine the relationship between the settling di stribution of settleable solids and their pollutant load - organic mas s, chemical oxygen demand, heavy metals and organic micropollutants. T o calculate where settleable solids from combined sewer systems will s ettle in receiving waters, the settling distribution is also useful. T he results of a three-year research indicate that stormwater treatment by settling is effective in preventing adverse environmental impacts of combined sewage pollutants.