Agricultural Research Management Information System

Home
Research Summary
Search
About Us
- ARMIS
- Brochure
Contact Us
Report
User Request
Data Input
Help
- Operation Manual
  - PDF
  - Video
- Program Area & Commodity
We have reached 37600 number of research entries at this moment.

- Logout

Research Detail

Home
Research
Detail

Microbiological Study on Supply Water and Treated Water in Dhaka City

Mrityunjoy Acharjee
Department of Microbiology, Stamford University Bangladesh

Sadia Afrin Beauty
Dhaka Water Supply and Sewerage Authority, Bangladesh

Farahnaaz Feroz
Department of Microbiology, Stamford University Bangladesh

M. Majibur Rahman
Department of Microbiology, Stamford University Bangladesh

Rashed Noor
Department of Microbiology, Stamford University Bangladesh

Farjana Rahman
Department of Microbiology, Stamford University Bangladesh

Abstract/ Executive Summary:

Water borne diseases are the major cause of morbidity and mortality in developing countries like Bangladesh, where disease outbreaks occur due to unsafe drinking water, inadequate sanitation and poor hygienic practices. The objective of this study was to evaluate the quality of water used for drinking as well as household purposes in Dhaka city, Bangladesh. Eighteen water samples were collected from different rivers and canals. Among those, two samples were treated with chlorine. Physico-chemical parameters (pH, salinity, turbidity, conductivity and dissolved oxygen) were monitored during the time of sample collection using portable meters. For microbiological analysis, water samples were collected in sterile screw capped bottle. All Experiments were carried out within 24 hours after collecting the samples. All the water sources were found to be contaminated with total coliform, faecal coliform, Escherichia coli, Klebsiella spp., Salmonella spp., Shigella spp., Vibrio cholerae, Aeromonas spp. and Fungi except treated water samples. Several biochemical tests were performed for confirmation of suspected organisms. According to these results, huge amount of total coliform and faecal coliform were observed in every sample and these amount were very much similar for other organisms. Treated water samples were found to be microbiologically accepted than untreated water samples.

Keywords: Microbiological Study, Supply Water, Treated Water, Dhaka City

Location: Department of Microbiology, Stamford University Bangladesh

Start Date: 00-11-2010

End Date: 00-01-2011

Program Area: Food Safety and Security

Commodity: Water quality

Objectives:

1. To understand the quality of Water and Sewerage Authority (WASA) water

Methodology:

The study was carried out to understand the quality of Water and Sewerage Authority (WASA) water in Microbiology Laboratory of Stamford University Bangladesh during the period of November 2010 to January 2011. Total 18 water samples were collected from different areas of Dhaka city. The local people use all of these waters for drinking or house hold purposes. In the case of water sample collection, water was collected from at least 2 different spots of each river and canal and then the samples were aseptically taken with presterilized screw capped bottle. The sampled bottles were marked properly and transported to the laboratory as early as possible. All Experiments were carried out within 24 hours after collecting the samples. All these samples were kept at 18 ºC until these were analyzed. Inoculation and incubation. MacConkey agar and media for fecal coliform (mFC) agar were routinely used to determine the total coliform and the fecal coliform, respectively by membrane filtration technique. Eosin Methylene Blue (EMB) agar was used for selective isolation of E. coli. Sabouraud Dextrose Agar (SDA) was used for fungal count. Spread plate technique was used to inoculate the samples on various culture media for enumeration of microbes. Six hours of enrichment in selenite broth and alkaline peptone water were done before inoculating the samples to the Xylose Lysine Deoxicolate Agar (XLD) and Thiosulfate Citrate Bile Salt (TCBS) agar in order to determine the presence of Salmonella, Shigella and V. cholerae, respectively. Bacterial count. Plate count was restricted to 30-300 colonies and plates containing more than 300 colonies were designated as too numerous to count (TNTC) and plates containing fewer than 30 colonies were designated as too few to count (TFTC). The following formula was used for enumeration. Number of cells per ml = number of colonies x dilution factor / volume of sample used (cfu/g). Identification of microorganisms. Identification of bacterial isolates was carried out by different biochemical tests such as Triple Sugar Iron Test (TSI), Motility Indole Urease test (MIU), Citrate Utilization test, Methyl Red (MR) Test, Voges - Proskauer (VP) test, Oxidase test and salt tolarence test. Treatment process of water. At first, water was transported from Shitolakhya River to DND canal and then from DND canal to Sydabad intake point. In this stage water was treated with chlorine and then conveyed to clarified stage. Here Alum Sulfate was mixed with water and transported to the filter bed for filtration and at the last stage again water was treated with chlorine to examine the last count of organisms and transported to the treated water tank very safely.

Source of Information:

Article Link (Online Journal):

Funding Source:

Total Budget (Tk.) :

Achievement/Findings:

The study showed that, among all sources of water, the Shitolakha river, Sharulia water, DND canal and Clarified water contained higher amounts of total coliforms, fecal coliforms, have E. coli and Klebsiella than other sources. It might occur due to the presence of hanging latrines around the rivers and canals. Faecal materials are also drained to rivers and canals by water run off during rainy season. It can be concluded that the treated waters are relatively free from microorganisms but the untreated ones are extremely polluted by bacteria and perilous pathogens. In addition, the quality of treated water samples from WASA were found to be microbiologicaly acceptable and hence it indicates that the treatment process of WASA is satisfactory.

Knowledge Management: Journal