The Yamuna also known as the Jumna or Jamna , is the second largest tributary river of the gangas (Ganga) and the longest tributary in india . Originating from the yamunotri Glacier at a height of 6,387 metres (20,955 ft) on the southwestern slopes of banderpooch peaks of the lower himalaya in uttrakhand, it travels a total length of 1,376 kilometres (855 mi) and has a drainage system of 366,223 square kilometres. It merges with the Ganges at triveni Sangam , prayagraj , which is a site of the kumbh mela, a hindu festival held every 12 years. Cleaning of Yamuna River Cleaning of Yamuna is also part of the Namami Gange Mission and Government of India has been supplementing the efforts of the States for checking the rising level of pollution of river Yamuna, a tributary of River Ganga, by providing financial assistance to States of Haryana, Delhi and Uttar Prad...