Spatial distribution of physico-chemical parameters for groundwater quality evaluation in a part of Satluj River Basin, India Akshay Kumar Chaudhry, Kamal Kumar and Mohammad Afaq Alam ABSTRACT The rising population, contamination and mismanagement of groundwater worldwide require sustainable management techniques and strategies to prevent misuse of groundwater resources especially in the semi-arid regions of the world. The aim of the present study is to assess the distribution of contaminants in groundwater at a spatial level by using a geostatistical method, namely ordinary kriging. For this, a physico-chemical parameter data set at 14 sampling locations for a period over 25 years was assessed. Three semi-variogram models, namely exponential, Gaussian and spherical, fitted well for the data set and were cross-validated using predictive statistics. Based on nugget/sill ratio, which characterizes the overall spatial dependence of water quality parameters, it was observed that, apart from nitrate, all the other parameters showed moderate to weak spatial dependence (i.e. total hardness), indicating significant influence of urbanization, fertilization and industrialization. Spatial distribution maps of all the parameters were generated. Concentration of most of the parameters reported high values in the northern region, while silicon dioxide and potassium recorded high values in the southern and central regions of the study area respectively. The study highlighted the depleting groundwater resources in various regions of the study area, indicating that the groundwater quality is in a declining state. Akshay Kumar Chaudhry (corresponding author) Kamal Kumar Mohammad Afaq Alam Department of Civil Engineering, Punjab Engineering College (deemed to be University), Chandigarh, India E-mail: akki016@gmail.com Key words | kriging, nugget, physico-chemical parameters, Satluj, semi-variogram, sill INTRODUCTION Groundwater is one of the vital resources of consumable water on earth, particularly in semi-arid regions. Nowadays, it is the most threatened resource, as the rate of extraction of groundwater is growing endlessly due to the increase in population growth, and agronomic and industrial-related activities. Hence, it has become an essential commodity in the recent past due to the increase in such activities. How- ever, rapid development in the recent past in agronomic and industrial sectors poses a great risk to the safety and well-being of people due to release of wastewater from industries and municipal sewage (Olayinka ; Ntengwe ). Wastewater released (directly or indirectly) if not properly treated and controlled can cause a serious threat to groundwater resources and can cause a wide range of damage to human health (Shankar et al. ). The most common diseases that can be transmitted through intake of contaminated water, inadequate sani- tation and poor hygiene are diarrheal diseases (WHO ). Groundwater, once contaminated, stays in an unu- sable condition for quite a long time or even hundreds of years. So, the issues related to groundwater contamination are a huge problem, which has caught the attention of social activists and researchers all around the world (Mishra et al. ). 1480 © IWA Publishing 2019 Water Supply | 19.5 | 2019 doi: 10.2166/ws.2019.015 Downloaded from http://iwaponline.com/ws/article-pdf/19/5/1480/570721/ws019051480.pdf by guest on 24 July 2022