Uttarakhand being a mountainous state having maximum area under forest cover, about 65% and provides large amount of freshwater river for Ganga basin where habitation and agriculture are dominant. The rising demand of drinking water due to population growth also leads to the water scarcity in the terms of availability of quality drinking water. Contamination mentioned by Central Pollution Control Board (CPCB), 2009 and low per capita availability of quality drinking water reported by Department of Science and Technology (Government of India), 2010-2015, are the key issues of the state. To understand the availability of safe drinking water it is necessary to understand the overall hydrology of the basin in a spatial domain. The utilization of advance tools and techniques such as spatial models, geo statistical tools, high resolution remote sensing data and numerical hydrological model in the present study will enhance and ensure the water quality issue of Himalayan state of Uttarakhand which is expected to serve the society living along the river basin as well as in mountainous systems. The study will ensure the availability of sufficient quality drinking water to the communities in the selected watershed of each districts, considering the environmental aspects and human health while assessing 26 water quality parameters like color, odour,taste, turbidity, pH, total hardness, iron, chloride, chlorine, fluoride, total dissolved solids, calcium, magnesium, copper ,manganese, sulphate, nitrate, phenolic compound, arsenic, cadmium, lead, zinc, chromium, alkalinity and coliform bacteria etc. and also provide feasible solution of sustainable availability of water. Geospatial water quality and quantity model help to find out the spatio-temporal analysis of contamination and particles movement in the watersheds. Modern geo statistical simulation algorithms can produce multiple subsurface realizations that are in agreement with the conceptual geological models. The quality modeling and monitoring will help in providing portable surface and ground waters to the citizens.