In the heart of India, the Mahanadi River Basin in Odisha is facing a silent crisis. As urbanization and population growth surge, the river’s water quality is deteriorating, posing significant challenges for drinking water supply and the energy sector that relies on it. A groundbreaking study led by Abhijeet Das, a researcher from the Department of Civil Engineering at C.V. Raman Global University in Bhubaneswar, is shedding new light on the complex interplay of factors affecting the river’s health.
Das and his team have employed innovative techniques to evaluate the spatiotemporal impact of superficial factors on surface water quality. Their research, published in the Journal of Hydrology: Regional Studies, uses a combination of advanced methods to identify hotspots of pollution and understand the underlying causes. “We wanted to go beyond just identifying polluted sites,” Das explains. “We aimed to understand the dynamics of water quality variability and the cumulative impact of various factors.”
The study utilizes Methods Based on Removal Effects of Criteria (MEREC), Multi-Criteria Decision-Making analysis through Additive Ratio Assessment (ARAS) modeling, and Machine Learning approaches like Random Forest (RF) technique. These tools help pinpoint locations most affected by sewage discharge, lowering of water table, dilution, and surface runoff. Over four years, the team collected and analyzed water samples from 16 different locations along the river, focusing on the monsoon period.
The results paint a concerning picture. More than 62.5% of the samples exceeded the allowable threshold for Total Kjeldahl Nitrogen (TKN), indicating significant pollution. High concentrations of chloride (Cl-) and nitrate (NO3-) were found at several sites, pointing to the impact of agricultural fertilizers and industrial effluents. Geogenic contaminants like fluoride (F-) were also detected above permissible levels, highlighting the complex nature of the pollution problem.
Geospatial analysis and IDW interpolation were used to create detailed maps, revealing the spatial distribution of pollutants. The study found that domestic wastewater and agricultural runoff are primary contributors to water quality deterioration. ARAS modeling ranked the sites based on their pollution levels, identifying SN-(8), (9), and (16) as the most critically polluted, unsuitable for human consumption.
The energy sector, which relies heavily on water for cooling and other processes, is particularly vulnerable to these changes. “The deterioration of water quality can have cascading effects on the energy sector,” Das notes. “It can lead to increased operational costs, reduced efficiency, and even forced shutdowns of power plants.”
The study’s findings have significant implications for water management and policy. The spatial distribution maps highlight the role of chloride, electrical conductivity, sulfate, and nitrate in affecting the Water Quality Index (WQI), indicating that both man-made actions and natural causes impact surface water chemistry during the monsoon season. The research also underscores the effectiveness of MEREC and RF models in classifying water quality, providing a more accurate understanding of the parameters at play.
As the energy sector continues to grow, the need for reliable and clean water sources becomes increasingly critical. This study offers a roadmap for identifying and addressing pollution hotspots, ensuring sustainable water management practices. “The poor water quality at different places needs immediate government attention,” Das emphasizes. “We hope our findings will inform policy decisions and drive action towards protecting and restoring the Mahanadi River Basin.”
The innovative approaches used in this research could shape future developments in water quality monitoring and management. By integrating advanced technologies and multi-criteria decision-making tools, researchers and policymakers can gain a deeper understanding of water quality dynamics, enabling more effective and targeted interventions. As the energy sector adapts to these challenges, the insights from this study will be invaluable in ensuring a sustainable and resilient future.
