Comprehensive assessment of drinking water quality in the highland region of Kotli Sattian, Pakistan

ABSTRACT This study presents the first comprehensive assessment of drinking water quality in Kotli Sattian, a highland tehsil of Rawalpindi District, Pakistan. Fifty spring and borehole samples were analyzed for physicochemical (pH, EC, TDS, hardness, alkalinity, major ions), microbiological (total bacterial counts, coliforms, Salmonella–Shigella), and trace-element (ICP-OES) parameters. pH ranged 6.5–8.5; EC and TDS reached maxima of 760 μS/cm and 673 mg/L, respectively, with Chenar and Lethral showing the highest ionic loads. Hardness exceeded the national limit (≤500 mg/L) at selected sites (Phofandi, Batahal). Microbiological analyses revealed fecal contamination in several villages (MacConkey counts to 55 CFU/mL), exceeding WHO recommendations. Trace-metal testing identified elevated barium (up to 1.0 mg/L; guideline 0.7 mg/L) and aluminum (up to 2.8 mg/L; guideline 0.2 mg/L) at localized sites. Multivariate analyses (PCA) indicate that geogenic carbonate dissolution and localized anthropogenic inputs drive spatial variability. Household surveys (n = 100) showed limited storage hygiene and widespread reliance on boiling. The results identify contamination hotspots and immediate public health concerns, and recommend targeted monitoring, household storage interventions, and infrastructure upgrades. These data establish a baseline for future multi-season surveillance in upland Pakistani communities.