Evaluation on the Quality of Bangkok Tap Water with Other Drinking Purpose Water

The concern of drinking purposed water quality in Bangkok, Nonthaburi, and Samutprakarn provinces has been a problem for over fifteen years. Metropolitan Water Works Authority (MWA) of Thailand is fully responsible for providing water supply to the mentioned areas. The objective of Drinkable Tap Water Project is to make people realize in quality of tap water. Communities, school, government agencies, hotels, hospitals, department stores, and other organizations are participating in this project. MWA have collected at least 3 samples of water from the corresponding places and the samples have to meet the World Health Organization (WHO) guidelines level. This study is to evaluate water quality of tap water, storage water, filtered water, and filtered water dispenser. The water samples from 2,354 attending places are collected and analyzed. From October 2011 to September 2016, MWA analyzed 32,711 samples. The analyzed water parameters are free residual chlorine, appearance color, turbidity, pH, conductivity, total dissolved solids (TDS), and pathogenic bacteria; E.coli. The results indicated that a number of tap water samples had the highest number compliance with WHO guidelines levels at 98.40%. The filtered water, filtered water dispenser, and storage water were received 96.71%, 95.63%, and 90.88%, respectively. However, the several samples fail to pass WHO guideline level because they were contaminated by E.coli. The result is that tap water has the highest score among other sources probably because tap water has chlorine for disinfection and always is monitored by professional team round-the-clock services compared to the other water sources with less maintenance or cleaning. Also, water quality reports are continuously sent to customers by mail addresses. Tap water quality data are shown on MWA websites and Facebook. All these steps of work should enhance the confidence of tap water quality