Abstract
Background: Kumaun region of the Himalaya is bountifully supplied by a variety of drinking water resources including lakes, rivers, streams, springs, brooks, etc. Mountain water springs are vital natural resources that have sustained civilizations, ecosystems, and wildlife for centuries. These springs, originating from high-altitude areas, provide pure freshwater that is often used for drinking, agriculture, and industrial purposes. Methods: The present study was undertaken to evaluate the physico-chemical characteristics and water quality of natural drinking water springs located in the Naini Lake basin of Nainital during the pre-monsoon period. Thirteen springs were selected, and water samples were collected in 2025 using a stratified random sampling approach. The analyzed parameters included pH, temperature, dissolved oxygen (DO), total dissolved solids (TDS), electrical conductivity (EC), turbidity, chloride, total hardness (as CaCO₃), fluoride, nitrate, and free chlorine, along with other selected chemical and microbial indicators. Result:The results indicated that spring water temperature ranged from 14.5 to 17.5 °C, while pH values varied from 7.0 (Tur Tur Dhara) to 8.8 (Near Ramleela Ground), indicating neutral to moderately alkaline conditions. Dissolved oxygen concentrations ranged between 6.0 and 7.5 mg/L, reflecting good oxygenation. Total dissolved solids showed considerable variation, with the lowest value of 189 ppm observed near Hanuman Gadi and the highest value of 434.6 ppm at Chartan Lounge Water Spring (I). Electrical conductivity ranged from 392 to 815 µS/cm.Turbidity was 0 NTU at most locations, except at Chartan Lounge Water Springs (II and III) where a maximum of 5 NTU was recorded. Chloride concentrations ranged from 10 to 40 mg/L, while total hardness varied between 225 mg/L (Near Jiwaji Cottage and Hanuman Gadi) and 450 mg/L (Birla Road and Chartan Lounge springs). Fluoride levels were generally low, ranging from 0.0 to 0.5 mg/L, and nitrate concentrations varied from 0.0 to 0.8 mg/L. Free chlorine was absent in all samples, indicating natural, untreated water sources. Conclusion: the physico-chemical quality of water from most natural springs was found to be within the acceptable or permissible limits prescribed by Indian Standard Specifications (ISI) for drinking water. Nevertheless, the observed spatial variability and increasing anthropogenic pressure highlight the need for regular monitoring, protection of recharge zones, and implementation of sustainable conservation strategies to safeguard these critical mountain water resources under changing climatic and developmental scenarios.

Key words: Physico-chemical parameters; Natural water springs; Drinking water quality; Pre-monsoon season; Nainital Himalaya