Evaluation of physical, chemical and microbial quality of distribution network drinkingwater in Bushehr, Iran

The physical, chemical and microbial properties of water are the criteria to consider it as drinking water quality. Unfavorable changes in such parameters may threat consumer's health. The aim of this study is to give a clear view of physical, chemical and microbial quality of distribution network drinking water in Bushehr and compare with national and EPA standards. This descriptive sectional study was done during Sep 2012 to Feb 2013 (6 months). 50 Samples were collected directly from distribution network drinking water in Bushehr. Physical and chemical analyses were done according to standard methods. Multiple tube fermentation method was used to determine fecal and total coliform bacteria and spread plate method was used to measure heterotrophic bacteria. The mean values of measured parameters were as follow: electrical conductivity 1155.5 µs/cm, turbidity 0.27 NTU, pH 7.12, alkalinity 171.5, total hardness 458.96, calcium hardness 390.96, magnesium hardness 68 mg/L as CaCO3, calcium 156.38, magnesium 16.95, residual chlorine 0.61, chloride 83.26, TDS 577.7, iron 0.115, fluoride 0.48, phosphate 0.059, nitrate 3.08, nitrite 0.003 and sulphate 728.38 mg/L. Total coliform (0), fecal coliform (0) MPN/100 ml and HPC 309.8 CFU/mL. Except TDS and sulphate, all cited results met the national and EPA standards. Quality of water from distribution network in Bushehr was not problematical from health point of view. However, high TDS and sulphate content may increase diarrhea risk in consumer as well as corrosive effect of water.