The present investigation was systematically conducted to evaluate the spatial and ecological health parameters of the Kewai River situated within the mineral-rich Anuppur district of Madhya Pradesh, India. Utilizing benthic macroinvertebrates as active biological monitors, structural ecosystem dynamics were analyzed alongside ongoing anthropological pressures. The river, a vital hydrological lifeline feeding the greater Son River system, experiences constant stress from adjacent open-cast coal mining infrastructures (specifically the Jamuna-Kotma and Sohagpur operational belts), thermal effluents, and untreated urban discharges. Seasonal sample extractions were executed across four distinct biological monitoring stations (S1 to S4) engineered to capture varying intensities of pollution inputs. A comprehensive total of 34 discrete macroinvertebrate family groups spanning three biological phyla (Arthropoda, Mollusca, and Annelida) were successfully recorded. The resulting baseline biological community structure mapped a visible over-abundance of highly pollution-tolerant benthic organisms, most notably Chironomidae (Diptera) and Tubificidae (Oligochaeta), at stations directly subject to active mine-water discharge zones (S2 and S3). Conversely, highly pollution-sensitive groups encompassing the Ephemeroptera, Plecoptera, and Trichoptera (EPT assemblage) were strictly confined to the ecologically uncompromised upstream reference zone (S1). Integrated biological performance metrics, including the Shannon-Wiener Diversity Index (H'), Simpson’s Dominance Index (D), and the comprehensive Hilsenhoff Family Biotic Index (HFBI), were calculated to determine structural organic and trace-chemical degradation. The computed HFBI matrix values registered from 4.2 (indicating clean water status at S1) up to a severe 7.8 (depicting highly poor biological quality at S3). This provides direct diagnostic evidence of significant eco-system degradation prompted by acid mine drainage (AMD) and ongoing industrial chemical leaching. This study explicitly proves that benthic macroinvertebrate community assemblages function as exceptionally viable, cost-effective biosensors for long-term health tracking of riverine setups adjacent to high-intensity mining zones, highlighting an immediate, crucial prerequisite for active regional eco-restoration and strictly enforced drainage basin management.