Groundwater quality in Paravanar river basin has significant characteristics and its consideration is unavoidable, since it’s a major source of water for drinking, industries and irrigation usage. The present study was carried out to assess the groundwater quality suitability for drinking in Paravanar river basin, Cuddalore district, Tamil Nadu, India. The rainfall frequency analysis was carried out in the basin area from 1971 to 2015 to delineate rainfall prominence years as drought, average rainfall, 75 % dependable rainfall and recent rainy years. In this study, nine parameters i.e., Electrical Conductivity (EC), pH, Total Dissolved Solids (TDS), Total Hardness (TH), Calcium (Ca²⁺), Magnesium (Mg²⁺), Chloride (Cl^-), Sulphate (SO₄^2-) and Nitrate (NO₃^-) were considered for computing the Water Quality Index (WQI) for the rainfall dependability years (1974, 1991, 2009 and 2015) by using weighted arithmetic index method for drinking purpose. Weighted overlay maps were prepared from the spatial distribution layers pertaining to WQI for the post and pre-monsoon seasons for the rainfall dependability years using ArcGIS 10.3. The results showed that the quality of water in Paravanar river basin was highly affected during post-monsoon than pre-monsoon period. More than 50 % of the basin area water samples weren’t really good enough for drinking without taking up water quality managing activities during post monsoon. Further, the water quality was highly degraded due to industrialization and agriculture activities compared to urbanization. The pollution control measures to improve the hazardous environment of industrial and agricultural practices, may develop the suitability area for drinking water in the basin.

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基于GIS的印度泰米尔纳德邦库达洛尔区Paravanar河流域地下水水质季节性变化及其适合饮用

巴拉瓦纳尔河流域的地下水水质具有显着特征，因此是不可避免的考虑因素，因为它是饮用水，工业用水和灌溉用水的主要来源。本研究旨在评估印度泰米尔纳德邦库达洛尔区Paravanar流域的地下水对饮用水的适宜性。在1971年至2015年期间对流域地区进行了降雨频率分析，将干旱，平均降雨量，75％的可靠降雨量和最近的雨年划分为突出年份。在这项研究中，九个参数即，电导率（EC），pH值，总溶解固体（TDS），总硬度（TH），钙（Ca ²⁺），镁（Mg ²⁺），氯化物（氯^- ），硫酸（SO ₄^2-）和硝酸盐（NO ₃ ^-）被认为是通过使用加权算术指数法（用于饮用目的）来计算降雨依赖年份（1974、1991、2009和2015）的水质指数（WQI）。使用ArcGIS 10.3，从与降雨相关年份的季风季节之前和季风季节有关的WQI的空间分布层准备了加权叠加图。结果表明，Paravanar流域的水质在季风后比季风前受到严重影响。流域地区超过50％的水样本在季风后没有进行水质管理活动的情况下，还不够好喝。此外，与城市化相比，由于工业化和农业活动，水质严重恶化。