Determination of pollutant sources and loads in İzmit bay

In this study general characteristics of İzmit Bay have been examined and obtained information about water quality of the Bay by making investigations and comparisons in the scope of researches made in the past years. Pollutant contents and loads resulting from the leakage water emanating from settlement, industry, brooks, shipping and solid waste storage that are mainly factors pollution in the Bay have been researched. Samples from the brooks that are leading in the pollutant sources have been taken. Parameters that have been investigated are chemical oxygen demand, biological oxygen demand, total kjeldahl nitrogen, total phosphor, total suspended solid matter and total organic carbon. In this way, loads entering into the Bay have been calculated by the pollutant parameters.It is seen that substantial part of pollutant loads entering into İzmit Bay have not been subjected to reclamation works and waste water of drainage comes from the brooks that are discharged without refining. When analyses made in the tail water of waste water treatment facilities are investigated it is seen that quality of tail water in biological and advanced biological facilities is conformed with the sea discharge standarts defined in the Water Pollution Control Regulation. However, even so waste water with high flow stemming from population density is treated they are substantially pollutant loads. It has been concluded that İzmit Bay will be preserved largely from environmental pollution if waste water is directly given to the bottom layers of the Bay by deep discharge method instead of they are discharged into the Bay by brooks after passing through advanced waste water treatment process.Key Words: İzmit Bay, pollutant sources, pollutant loads