Physico-chemical changes and ecological degeneration of Sone River because of sand mining: Field study report

River sand mining has gained international attention as an unprecedented anthropogenic impact on riverine ecosystems globally, particularly in developing countries that are facing rapid rates of population growth. The present study focused on the impact of sand mining on the physicochemical parameters of Sone River located in Dehri, Bihar. A field investigation of one-year duration was carried out in five different locations, categorized as Heavy Mining, Moderate Mining, and Control/No Mining sites, according to levels of mining intensity and disturbance observed. Monthly water samples were collected and laboratory tests conducted for major physico-chemical parameters in water, such as water temperature, pH, turbidity, total dissolved solids (TDS), total suspended solids (TSS), dissolved oxygen (DO), biochemical oxygen demand (BOD), chemical oxygen demand (COD), alkalinity, hardness levels in water, and chloride. Hydrological data, such as depth, velocity, and discharge, were also measured. The results indicate a specific trend for water quality variation in mining areas that worsened over time with mining. Values for turbidity, TDS, BOD, CO, alkalinity, hardness, and low DO values are all very high in mining areas, showing a decline in natural purification capacity. The water chemistry values in non-mining areas consistently showed a steady trend, suggesting that sand mining has a considerable effect on river hydrology. It may eventually lead to a decline in ecosystem quality. This highlights the varying needs for environmental protection, the need to have strict laws implemented, to follow environmentally friendly sand mining procedures, and to look at the water quality. Conserving the natural resources in an eco-friendly manner requires an integrated approach towards managing the rivers and preserving the resources for future generations.