Application of index analysis to evaluate the water quality of the Tuul River in Mongolia

A study of the Tuul River water pollution was carried out in surrounding area of Ulaanbaatar, the capital of Mongolia at 14 monitoring sites, using a dataset between 1998-2008. An index method applied to assess water quality and seven hydro-chemicals used in the index calculation. The research indicates that the river is not polluted until the Ulaanbaatar and the contamination level spike appears when the river entering the city.