Evaluation of Microbiological Water Quality and Coastal Waters Quality Index of Persian Gulf in Bandar Abbas Coastal City, Iran

The goals of this study were to assess the microbiological quality and coastal water quality index (CWQI) in the Persian Gulf alongshore of Bandar Abbas city. Water samples were collected from five different coastal sites in spring and summer seasons. To assess the microbiological quality: Total Coliforms, Fecal Coliforms, Fecal Streptococci and Clostridium perfringens were measured. Also, eight physicochemical parameters (DO, BOD, TSS, Turbidity, Temperature, pH, Nitrate, Phosphate) were examined for calculating the CWQI. The mean for microbiological indicators was respectively, 3667, 1055, 50, 211 MPN/100ml. for physicochemical parameters, the average of water temperature was 32 °C, electrical conductivity was 57mmho/cm, the turbidity was 70.7 NTU, pH 8.1, and also the average concentration of phosphate, nitrate, nitrite, and ammonium was 180, 18.2, 4.9, 12.16μmol/L, and the mean of concentration BOD, COD and DO were 4.89, 11 and 6.8mg/L, respectively. In addition, the water quality index for all months and at selected stations was 65. The results showed that in the most samples the levels of microbiological indicators were exceeded the national standard and guideline values. Also, the computed CWQI showed that quality of water was weak. All the extracted results are closely related to the inlets connected to the sea. These inlets except the Ghadir station will affect the rest of the stations. In general, in low tide, the Bactria index was more than high tide