Chittagong is the second largest city in Bangladesh and its premier sea port and industrialized city. Due to its economic activity it has led to a large population influx. Chittagong Water and Sewerage Authority (CWASA) is the responsible authority for supplying water to the city dwellers, which is being use for drinking purpose also. But the kind of population and urban growth Chittagong is going through, presents tremendous challenges to the utility authority in providing utility services. The water supplied by the CWASA is being treated by Mohra Water treatment Plant and Kalurghat Iron removal Plant. But the problem of water shortage, compounded by pollution, is causing indisputable harm to the city by posing a serious risk of microbial contamination of drinking water. The aim of the study was to reveal the present water quality, more importantly microbial water quality of the supplied water of CWASA, to assess the reasons or influencing factors and to discusses major deterioration mechanisms that may contribute to water quality failure. Samples of water from the raw water source, treated water before entering distribution network, from distribution network and consumers’ reservoir were collected and tested for some microbial (total coliform, fecal coliform and Escherichia coliform) and chemical parameters. Some formal and informal discussion with CWASA employee and direct observation were also used for data collection during the field survey. The results show that various parameters (Maximum values distribution network/ consumers’ reservoirs: TC: 8/100ml / 4/100ml, FC: 3/100 ml / 3/100ml, EC: 1/100ml / 2/100ml, Turbidity: 41 NTU/ 15 NTU and Minimum Residual Chlorine: 0mg/l / 0 mg/l) analyzed in the samples exceeded the Bangladesh Environmental conservation Rule, 1997 and WHO Guideline for drinking water. About 17.5% samples were found to be microbial contaminated in the distribution network, but in reservoirs the contamination was 45%. It is not that the supplied water is always of poor quality, but due to longer retention time in users’ reservoir the chance of contamination gets higher and the water deteriorate. Insufficient and centralized chlorination, pre chlorination, pipe leakage, damage and corrosion, absence of any sewer system in the city, pipe alignment close to sewage system or open drains, pressure fluctuation in net, lack of proper maintenance of distribution network and consumers’ reservoirs, lack of public awareness, unplanned urbanization etc. have been found as the crucial role in water quality deterioration. To improve the present water quality, increment of post chlorination dose, decentralized chlorination, use of biological filters for algae removal, appropriate maintenance of distribution network, regular sanitary inspection, regular assessment of water samples from the net, proper maintenance of consumers’ reservoirs, involvement of local public in maintenance activity and lots of others measures have been proposed. But organizing public awareness and capacity building program along with above mentioned recommendation have been given a higher priority to confirm a secure investment in Safe Drinking Water and Health.

TITLE - Assessment of Microbial Quality of Supply Water in Chittagong City, Bangladesh
AUTHOR - Farhana Chowdhury
••••••IJSER Edition - March 2014

UNIVERSITY - Karlsruhe Institute of Technology
GUIDE NAME -
Dr.-Ing Stephan Fuchs
Prof. Dr. rer. nat. Ursula Obst