This book explores the core of Physical Geographical Science, spotlighting its vital role in understanding Earth's natural systems. Focusing on the Hindu Kush-Himalaya region-the "Third Pole"-it highlights urgent water quality issues amid climate change and human pressures. Introducing the Himalayan Mountain Water Health (HMWH) framework, it calls for integrated, science-based monitoring. Emphasizing tools like GIS, remote sensing, and modeling, the study repositions physical geography as key to sustainable environmental solutions.