2.4 Sample Collection
Surface water samples of the rivers were collected from four different points of the river in two seasons during the
period of April 2013 to July 2013 covering dry and wet periods. Various water quality parameters were monitored
and a detailed field survey has been conducted within the study area. Proper sampling procedure was followed while
collecting the samples.
2.5 Sample Handling and Preservation
Appropriate sample handling and preservation is essential to ensure data quality. Factors considered are listed as:
(a) clean plastic containers are typically used for inorganic samples, with glass containers used for organic analyses;
(b) proper sample preservation is important if accurate and representative results are to be obtained from the sampling
efforts. In general, all samples are placed on ice in the dark and (c) analyses should be initiated as soon as possible
after collection to avoid sample deterioration.
2.6 Sample Depths
Selection of sampling depth varies with the purpose of work and the parameter to be tested. In this study, the
sampling depth was taken to be 15- 20 cm. This was because; the main point of focus of this study was surface water
pollution. Generally, heavy metal concentration analysis needs sample from a deeper section.
2.7 Laboratory Testing and Standards
The experiment on a selected segment of the river was carried out for four months duration. The time was chosen
as such that both dry season and wet season was there. To assess the water quality we conducted test on 13 water
quality parameters. The lists of those parameters with the standards are listed below:
From the analysis of data it was observed that there is a distinct variation in water quality during dry and wet
season. As the flow of water is less during dry season and water level goes down the quality of water become poor.
As a result water remains more polluted during dry season. Again during wet season due to rainfall the flow is more,
level of water increases and the water quality becomes relatively better.
2.8 Determination of Water Quality Parameters
Dissolved Oxygen (DO): The sample was taken in the bottle and diluted with the water. The probe of the
multimeter was placed inside the bottle and the reading is taken.
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