Assessment of Groundwater Vulnerability Using GIS and DRASTIC for Upper Palar River Basin, Tamil Nadu

Abstract

Groundwater is one of the valuable resources and due to increase in the population, industrialization and agriculture practices, the groundwater stress has increased to a greater extent. Once the groundwater gets contaminated, remediation is very difficult. The steps to measure the groundwater vulnerability must be taken for sustainable groundwater protection and management planning. In this paper, the DRASTIC model is applied to find out and generate a small-scale map of groundwater vulnerability to assess the contamination in the upper Palar river basin, Tamil Nadu, India. A number of tanneries are located along the banks of the river basin. The quality of groundwater in and around river basin area has been affected very much due to the untreated effluent of the tanneries discharged directly to the river. The DRASTIC model consists of seven hydrogeological parameters including depth to water table, net recharge, aquifer media, soil media, topography, impact of vadose zone and hydraulic conductivity; each factor is assigned by weight and rating which depends upon the influence of the seven hydrological layers of the river basin area. The ArcGIS 10.3 software was used to create the groundwater vulnerability map by overlaying the seven layers, which is intended to show potential areas of groundwater contamination. The results of the study shows that, 50% of the study area falls under very high pollution potential zone, 20% under high pollution potential, 15% under moderate pollution potential, 10% under low pollution potential, and the remaining 5% of the area has no risk. The very high vulnerability class which is covered by the alluvium along the river course is most likely to pollution due to the very lower slope terrains in the direction of the central part, which allows better percolation of contaminants into the groundwater. The low vulnerability class lies in the area covered by the hard rock and clay loam soil in the upper reach of the Palar river which contains mountains and hard rock terrain.

Utilizing Geological and Geoelectrical methods in a GIS-based DRASTIC model of the Probable Groundwater Vulnerability in the Southern Nigerian Raffia Metropolis of Ikot Ekpene and its Surroundings

“…Aquifer media refers to the geological components that make up the aquifer. The permeability of the aquifer media, as indicated by the size of the grains in the aquifer materials (Ekanem et al, 2021), governs the reduction of contaminants (Amiri et al, 2020;Venkatesan et al, 2019). Aquifer geomaterials with higher permeability will have a reduced ability to remove contaminants, making them more vulnerable to contamination (Neh et al, 2015;Jaseela et al, 2016;Venkatesan et al, 2019;Amiri et al, 2020).…”

Prioritization of watersheds for land and water management in lower Sutlej River Basin using geospatial technology

“…Stream frequency (F s ) measures the ratio between the total number of streams in a basin area and the total number of streams (Horton, 1932). Fs are classified as very high (20-25), high (15-20), moderately high (5-10), moderate (10-15), and low (0-5) (Venkatesan, 2014). The texture of the drainage network is replicated by stream frequency, which is typically decided by the lithology of the basin.…”

Aquifer Upper-Middle Pleistocene (qp2-3) vulnerability assessment using origin DRASTIC and improved AHP- DRASTIC in Ho Chi Minh City

“…Môi trường GIS cung cấp môi trường hiệu quả, tạo điều kiện phân tích và trực quan hóa khối lượng lớn dữ liệu không gian một cách nhanh chóng, hỗ trợ quá trình ra quyết định trong nhiều lĩnh vực 17,18 . Điển hình tại Palestine 2 , Jordan 19 , Ấn Độ [20][21][22][23] , Pakistan [24][25][26] , Iran 27,28 , Kerman 29 và Bangladesh 30 đã áp dụng DRASTIC với trọng số cố định theo phương pháp gốc, thực hiện trên nền tảng GIS để thành lập bản đồ phân vùng tính dễ bị tổn thương của các tầng chứa nước. Mức độ dễ bị tổn thương thông qua chỉ số DRAS-TIC với trọng số cố định được sử dụng rộng rãi trong nhiều nghiên cứu nhưng không hoàn toàn phù hợp với điều kiện địa chất, tự nhiên thực tế của các khu vực khác nhau.…”