International Journal of Scientific Research and Review ISSN NO: 2279-543X
ASSESSMENT OF GROUNDWATER
QUALITY IN PALLAVARAM AREA BY
WQI METHOD
Arthika B, Maheswari K
1Assistant Professor, Department of Civil Engineering, Vels Institute of Science, Technology & Advanced Studies, Chennai, Tamilnadu 2Assistant Professor, Department of Civil Engineering, St.Joseph’s institute of technology, Chennai, Tamilnadu
Abstract
Dumping of solid wastes in water bodies causes contamination and it creates severe impact on deterioration of Groundwater. Groundwater is the major source of drinking and it can be used for domestic use as well as public use. Our study focuses on the deterioration of Groundwater Quality due to dumping of solid wastes in Pallavaram area. The study area has been chosen around the Pallavaram lake and 11 sampling locations were taken. The present study was undertaken to characterize the physicochemical parameters such as pH, Electrical Conductivity (EC), Hardness (H), Total Hardness (TH), Chloride (Cl), Total Dissolved Solids (TDS). Each parameter was compared with its standard permissible limit as prescribed by World Health Organization (WHO).
Keywords: Groundwater, WQI, Solid waste
I. INTRODUCTION
Dumping of solid wastes in water bodies causes contamination and it creates severe impact on deterioration of Groundwater. Groundwater is the major source of drinking and it can be used for domestic use as well as public use.Water Quality Index is one of the most effective tools to communicate information on the quality of water to the concerned citizens and policymakers. It is an important parameter for the assessment and management of ground water. A Water Quality Index is a numeric expression used to transform large number of variables data into a single number as index, at different times and in different places, which represents the water quality level and to translate this information into a single value defining the period of time and spatial unit involved and to be easily understood by managers.. The index is based on the attainment of water quality objectives. Quality objectives are for safe limits, set by the ministry in areas of human areas, to protect the most sensitive water uses of water resources. Water index defines a systematic way of interpretation and measurements of water quality naturally or desirables. The index of water quality into five categories: excellent, good, fair, borderline, and poor.
Volume 7, Issue 12, 2018 Page No: 535 International Journal of Scientific Research and Review ISSN NO: 2279-543X
II SCOPE OF THE STUDY
The water quality of groundwater in this area has deteriorated mainly due to extensive solid waste dumpsite seriously affected due to the combined effect of industrialization and urbanization. Awareness should be done to reduce contamination. The following objectives were made to assess the Groundwater, such as
1. To collect groundwater samples from the given location. 2. The water quality parameters such as pH, Electrical conductivity, Total dissolved solids, total alkalinity, total hardness, chloride and turbidity will be analysed to compute WQI by using Weighted Arithmetic Index Method.
III .STUDY AREA The study area Pallavaram Township is an industrial area located in Chennai Metropolitan city, Tamil Nadu. The geographic location of the area is between 80°07’30” to 80°10’56” East longitude and 12°57’13” to 12°58’56” North latitude. Sewage and dumping of garbage which has adversely affected the quality of the groundwater. The study area is 13 km away from the Bay of Bengal. A large number of tannery industries are located for about two kilometres length on both sides of the road. The area has lot of large scale and small scale tanning industries. Chrome tanning is the popular method practiced in this area. The area has Periya eri (big tank), once a sprawling water body covering about 189 acres, now shrunken into to small patch and used as storage for effluents from leather industry, sewage and dumping of garbage which has adversely affected the quality of the groundwater. Unpleasant smell prevails in the locality surrounding this area due to the heavy loads of industrial effluents. The climatic condition is hot during summer (March to June) and cold during winter season (November to January). The area receives rainfall from both south-west (June to September) and northeast monsoon (October to December) and the area enjoys a tropical climate. The climate of the area is with low humidity and high temperature, and the temperature is around 18ºC - 25ºC during winter and during summer has a maximum of 35ºC - 42ºC and is generally hot. Temperature starts rising towards the end of February. Geologically the study area is covered by crystalline rocks of Archaean age consisting of Charnockite formation.
Figure 3.1 Study Area
Volume 7, Issue 12, 2018 Page No: 536 International Journal of Scientific Research and Review ISSN NO: 2279-543X
IV METHODOLOGY AND TESTING
4.1.1 Sampling Water quality data sampling was carried out during January (post–monsoon) by using GPS survey. The groundwater samples were collected from the 11locations around the Pallavaram Lake and analyzed for 7 physicochemical parameters. The parameters pH, Electrical conductivity, total dissolved solid, total alkalinity, Total hardness, Chloride and Turbidity were analyzed in the laboratory as per the standard procedure of APHA. The latitude and longitude values of the selected sampling locations are given in Table 4.1. The collected samples were preserved by adding appropriate reagents in laboratory to determine the water quality analysis. These samples were analysed for different parameters as shown in Table 4.2.
Table 4.1 Groundwater sampling locations
Sample No. Latitude Longitude 1 12.9583073 80.1492741 2 12.9578492 80.1491611 3 12.9568787 80.148605
4 12.9568228 80.1485637 5 12.9556351 80.1495339 6 12.9557095 80.1495086
7 12.9544199 80.1497375 8 12.9529012 80.1528075 9 12.9559785 80.152007
10 12.9588424 80.1495706 11 12.9656428 80.1623456
Table 4.2 Analytical methods adopted for physicochemical analysis
Sl. No Analysis Method/instrument 1 pH pH meter 2 Electrical conductivity (EC) Conductivity meter
3 Total dissolved solid(TDS) Computation
4 Turbidity Turbidity meter
5 Total hardness Titration method
6 Chloride Titration method
7 Alkalinity Titration method
4.1.2 WQI Calculation
For computing WQI three steps are followed. In the first step, each of the11 parameters has been assigned a weight (wi) according to its relative importance in the overall quality of water for drinking purposes (Table 4.2).
Volume 7, Issue 12, 2018 Page No: 537 International Journal of Scientific Research and Review ISSN NO: 2279-543X
The maximum weight of 5 has been assigned to the parameter chloride due to its major importance in water quality assessment. Other in the second step, the relative weight (Wi) is computed from the following equation