Hydrometric assessment of Himalayan springs using classical hydrological methods for springshed management

Springs represent critical lifelines for mountain water security; however, discharge reductions and seasonal drying increasingly threaten 1.3 billion people dependent on Himalayan water systems amid accelerating climate change. This study presents a systematic application of classical hydrological methods across eight representative springs in the Tawi catchment, J&K UT, India, providing a comprehensive and unprecedented hydrometric assessment framework for data-scarce regions of Indian Himalayas. Three complimentary hydrological approaches were adopted: (1) flow regime analysis using hydrograph assessment and base flow separation, (2) statistical assessment using correlation and persistence functions, and (3) flow reliability evaluation using duration curves and variability indices. Results revealed distinct hydrological signatures: three springs exhibited perennial behavior with high base flow indices (0.67-0.88), strong groundwater contribution (> 800,000 L total volume), and low variability (CV < 0.3), while five springs demonstrated seasonal-flashy responses with discharge variability ratios exceeding 2.5. Cross-correlation analysis identified response lag times ranging from immediate (1 day) for shallow systems to 49 days for deeper groundwater-fed springs. Auto-correlation functions revealed memory of 14-49 days, indicating varying aquifer storage capacities. The evidence-based classification supports development of targeted community interventions: stable springs require recharge zone protection and forest conservation, whereas vulnerable springs necessitate artificial recharge structures, check dams, and community-based storage systems. This framework directly supports UN Sustainable Development Goal 6 (Clean Water and Sanitation) and Goal 13 (Climate Action), demonstrating that systematic, scientifically robust classical methods offer cost-effective alternatives for springshed management, thereby supporting mountain water security globally.