Spatio-temporal variations in water quality of Rispana river in Dehradun, India

Rivers are natural freshwater resource fulfilling domestic, agriculture, and industrial needs but urbanization, industry, intensive farming practices, environmental pollutions and climate change led to the deterioration of rivers and natural watershed. In Dehradun, one of the major water resource Rispana river is also suffered from anthropogenic activities and its water quality and quantity reduced to a critical level in the recent past. The work was carried out on a spatio-temporal basis in four different locations in pre-rains, rainy season and post-rains during 2022. Sample collection and analysis were done as per standards in the laboratory for various parameters to calculate the water quality index-WQI by adopting the weighted arithmetic index approach. It was observed that WQI varies from 44.53-302.69. The WQI at Shikharfall region (Kairwan Gaon) is good (44.53) and in Mothrowala (Doon University) it is not fit to utilize (302.69) as per quality standards. The water quality was poor-unfit in 75% of samples and the main contributing factors are low DO, high BOD and very high Coliform bacteria levels which exceed permissible limits in all samples. River water regulation by municipal authorities and discharge of waste from domestic and run-off sources enhance the pollutants and sediments in Rispana. Regulatory regimes must be executed for controlling unsustainable development approaches and water pollution in river catchments in Dehradun so that worth and magnitude of river Rispana water could be improved. To rejuvenate water resources for sustainable utilization is a main mandate for development. It is well addressed in the sustainable development goal (SDG: 6)-Clean Water and Sanitation.