Microbiological Quality Assessment of Drinking Water at Al-Hayy City, Southern Iraq.

Abstract

The microbial quality of drinking water which distributed form Al-Hayy water treatment plant and number of residential areas fed by these water treatment plant was studied each month over six month during a period extended from the October 2016 to April 2017,through the purification stages up to residential sites at different areas situated with various distances from the supplying source, two samples were taken monthly. This station derived their water from AL-Gharraf River in the southeastern part of Iraq, where the feed areas of the city with drinking water. This study included detection of bacteria, evidence of contamination of water (coliform, faecal coliform, Escherichia coli, faecal streptococcus bacteria and total bacteria count), also some physical and chemical variables ware like (temperature, turbidity, free residual chlorine and pH) . Results of Bacteriological tests showed increasing in TPC, TC, FC, E.coli and FS bacteria in December and January in all study locations as compared to those of the other months for water plant raw and drinking water and the FS values were less than other bacterial types for water plant. The TPC results of drinking water exceed 100 cell/ml, the allowable limit for drinking water, for all samples of water plant. On the other hand the TC, FC and E.coli exceeded zero cell/100ml, the allowable limit for drinking water, in many drinking water samples for water plant with increasing of temperature in summer months. Physiochemical tests showed that air temperature at sampling time was varied between17 and 34°C and between11.5 and 29°C, for water temperature at sampling time also. The results of pH means were within the allowable limit, ranging from 7.2 in October to 7.9 in April.The highest mean value of turbidity recorded for raw water was in December with 89 NTU and the lowest value was in April with 30 NTU, while the highest mean value recorded for Drinking water was 20 NTU again in December and the lowest value was 1 NTU in April. The highest mean value of residual chlorine was recorded in March with 3.8 mg/L, the lowest value was 0 mg/L in some of the farthest points of the plant.