In Dehradun capital city of Uttarakhand state (India) a major water resource Rispana river is highly contaminated due to anthropogenic activities and its water quality and quantity reduced to a critical level in recent past. The work was carried out on spatial basis in 4 different locations in pre-monsoon season during 2022. Sample collection and analysis was done as per APHA in laboratory for various parameters to calculate the water quality index-WQI by adopting the weighted arithmetic index approach. In this study it was observed that WQI varies from47.8 – 299.05 with an average of 146.14 (indicating a very poor quality & unfit for domestic purpose). Coliform levels are also very high (.2419.6 MPN) at majority of sites. River water harvesting at upstream region by municipal authorities led to reduced streamflow and discharge of waste from domestic and run-off sources contaminates the Rispana. Regulatory regimes must be executed for controlling unsustainable development approaches & water pollution in river catchments in Dehradun so that water quality and quantity of river Rispana could be enriched. To rejuvenate the water resources for sustainable utilization is a main mandate for development as per SDG 6.