Contamination in Drinking Water Supply: A Case Study of Shimla City, Himachal Pradesh, India

Shimla city is the capital of the hilly state, Himachal Pradesh. It is situated in the south of river Satluj. The drinking water supply to major portion of the city is met through Ashwani Khad and Dhalli water supply schemes. Ashwani Khad water treatment plant (WTP) receives water from a natural stream, Malyana sewage treatment plant (STP) treated water, and three open drains. During lean period, the treated water is supplemented with bore well water to fulfill the demand and is supplied to consumers after chlorination. Dhalli WTP receives water from Churat Nallah and Sayog catchment, and supplied to consumers after treatment. A mass level jaundice was reported in the Sanjauli-Malyana area of Shimla City during 2006–2007. In view of this, study of contamination in drinking water sources of Shimla City was carried out using hydrological and water quality data analysis. In the present paper, the causes of contamination in drinking water supply and options for ameliorative measures have been identified and discussed.