Dredged material of Izmir harbor: its behavior and pollution potential

Abstract

The Arap and Melez Rivers discharge to Izmir Bay bringing wastewater together with rainwater coming from their catchment areas. There is an artificial harbor built at the discharge point of the Melez River acting as a sedimentation area for the suspended matter carried by these rivers. This area has a storage capacity of 3 to 4 years. After this period, the sediments are dredged and disposed from the region. In this study, various studies were carried out in order to determine the geotechnical properties and pollution parameters of the sediments; the results of many previous studies are also given. In the analyses done on dredging samples, it was observed that sulfur, oil and grease, phosphorus, nitrogen and heavy metal concentrations were very high. The reason for these high concentrations is the direct discharge of untreated wastewater formed in the industries located along the Arap and Melez Rivers. The pollutants carried to Izmir Bay by these rivers then settle down inside the artificial harbor and reach high concentrations in bottom sediments. As a result of this study, some possible environmental effects of land disposal of this material are discussed and suggestions are given for final disposal alternatives.