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

Analysis of Groundwater Quality in Sylhet District

M Islam*
Assistant Professor, Department of Irrigation and Water Management, Sylhet Agricultural University, Sylhet, Bangladesh

A G Polash
MS Student, Department of Irrigation and Water Management, Sylhet Agricultural University, Sylhet, Bangladesh

S A Fahim
MS Student, Department of Irrigation and Water Management, Bangladesh Agricultural University, Mymensingh, Bangladesh

Abstract/ Executive Summary:

The present study was conducted to evaluate the groundwater quality at different locations in Sylhet district. The selected locations were Sylhet Agricultural University (SAU), Chowkideki, Tilagor, Golapgonj, South Surma and BADC pump at Daudpure. Temperature, pH, turbidity, total alkalinity, dissolved oxygen (DO), carbondioxide (CO2) and iron (Fe) were tested in the water quality laboratory of Sylhet Agricultural University and Leading University, Sylhet. Further water concentration data in the form of pH, turbidity, temperature, total alkalinity, carbon di oxide (CO2), iron (Fe), phosphate (PO4), nitrate (NO3), total hardness and total dissolved solids were collected from Bangladesh Agricultural Development Corporation (BADC). All the parameters were compared with laboratory tested samples and evaluated with Bangladesh water quality standard whether it is suitable or not. The tested quality parameters were found within the acceptable limit for irrigation and domestic purposes. At Golapgonj, the value of iron (2.01 mg l-1) was beyond the acceptable limit. Total alkalinity was found beyond permissible limitfor both domestic and irrigation purpose at Daudpure (124 mg l^-1) and Golapgonj (432 mg l^-1), respectively. From quality point of view, groundwater is suitable for domestic and irrigation purposes except excessive iron presence in the well. A correlation matrix was done to find out the interrelationship among different water quality parameters. It is found that significant positive correlation holds among the water quality parameters. Therefore, it is suggested that the geologic stratification of this region should be thoroughly investigated before installing a tubewell for both domestic and irrigation purposes.

Keywords: Groundwater, Quality parameters, Iron, Irrigation, Sylhet

Location: Sylhet district

Start Date:

End Date:

Program Area: Crop-Soil-Water Management

Commodity: Groundwater, Water quality

Objectives:

The current study is conducted with the objectives to analyze the water quality parameters, and to evaluate the groundwater quality for drinking and irrigation purposes.

Methodology:

Study site Sylhet city is located between 23⁰59′ and 25⁰13′ north latitude and 90⁰54′ and 90⁰30′ east longitude in the north-eastern region of Bangladesh. It is situated on the bank of river Surma. Sylhet city has a population of 500,000 people having a high population density (Ahmed et al., 2010).The main source of water supply is groundwater with deep tube well (DTW) in Sylhet city. Most of the city dwellers are highly dependent on groundwater to fulfill their daily needs. Such huge quantity of water is distributed by municipal water supply and privately installed DTW. The hydrogeological conditions in greater Sylhet are less favorable for the abstraction of groundwater than in most areas of Bangladesh. As a consequence, relatively few wells have been drilled in the area. The study sites are selected based on accessibility, aquifer depth, water quality status etc. Parameters to be analyzed Water quality parameters in the form of concentration were collected from both primary and secondary sources. The parameters are pH, turbidity, total dissolved solids, total hardness, dissolved oxygen, carbon dioxide, nitrate, total alkalinity, phosphate, iron and temperature. Sampling procedure Each sample was collected using a clean one liter plastic bottle with a screw cap which was thoroughly washed and cleaned with distilled water. The sampling tubewells were pumped for at least 30 minutes and then samples were taken in plastic bottles. The samples were taken monthly at 11.00 am in each location. The samples were packed properly to make the sample free from air contact. Then the samples were taken to the laboratory and tested within 24 hours. All the chemicals were used based on the analytical grade and the tests were conducted in accordance with the techniques described by American Public Health Association (APHA, 2005). Determination of groundwater quality parameters The pH was determined by using Lida instrument pH meter. It was standardized with a buffer solution of pH range between 4-9.Temperature of water samples were taken in situ measurement using a mobile thermometer. This was done by dipping the thermometer into the sample and stable readings were recorded. For determining total alkalinity100 ml of the sample was pipetted into a clean 250 ml conical flask. Two drops of methyl red indicator were then added and the solution titrated against a standard 0.02N H2SO4solution to a pink end-point. Total alkalinity (mg l^-1) = Total ml of acid used * 10 ppm. Turbidity was determined using a standardized Hanna H198703 Turbidity meter. The samples were poured into the measuring bottle and the surface or the bottle was wiped with silicon oil. The bottle was then inserted into the turbidity meter and the reading was obtained.CO2was determined by taking 100 ml of sample into a beaker and same quantity of distilled water into another. 10 drops of phenolphthalein indicator to each beaker was added. N/44 solution hydroxide from a burette was added to the sample and stirred until permanent pink color appears as compared to distilled water. CO2 (mg l^-1) = ml of N/44 * 10. For determining iron at first 100 ml sample was taken in a conical flask and taken distilled water in another. Then 5 ml dilute HCL and 5 ml potassium thiocyanate was added in both samples. 1ml standard iron solution was added in distilled water and the change in color was compared with the sample. A modified Winkler method is used for measuring dissolved oxygen. Manganous ions read with oxygen in the presence of potassium hydroxide precipitate (Step-1). An azide is present to prevent any nitrite ions from interfering with the test. On addition of acid, manganese oxide hydroxide oxidizes the iodide to iodine (step-2). Since the amount of iodine generated is equivalent to the oxygen in the sample, the concentration of iodine is calculated by titration of thiosulphate ions that reduce the iodine back to iodide ions. All the tested parameters have been compared with the permissible limit set by guidelines of Bangladesh water standard 1997 and evaluated whether the water is suitable for drinking, irrigation and industrial purposes or not. Analysis of water quality parameter Using the compiled data the spatial variations of chemical parameters were analyzed. Interpretive analyses for different users such as irrigation and domestic users were made in different locations. Statistical analysis was done in order to calculate correlation coefficients. Correlation matrix was constructed by calculating the coefficients of different pairs of parameters.

Source of Information: J. Sylhet Agril. Univ. 4(2):325-330, 2017 ISSN: 2308-1597

Article Link (Online Journal): www.jsau.com.bd

Funding Source:

Budget:

Total Budget (Tk.) :

Achievement/Findings:

From quality point of view, groundwater is suitable for domestic and irrigation purposes except excessive iron presence in the well. A correlation matrix was done to find out the interrelationship among different water quality parameters. It is found that significant positive correlation holds among the water quality parameters. Therefore, it is suggested that the geologic stratification of this region should be thoroughly investigated before installing a tubewell for both domestic and irrigation purposes.

Knowledge Management: Journal