The literal meaning of the word Teesta is Trishna (desire) which never ends. The legend of the Teesta River is mentioned in KalikaPurana. Among the other rivers of northern India, Teesta River is also called as younger daughter of Himalaya.
The Teesta River originates from the Pahunri (or Teesta Kangse) glacier above 7,068 m, and flows southward through gorges and rapids in the Sikkim Himalaya. The river then flows past the town of Rangpo where the Rangpo River joins, and where it forms the border between Sikkim and West Bengal up to Teesta Bazaar. Just before the Teesta Bridge, where the roads from Kalimpong and Darjeeling join, the river is met by its main tributary, the Rangeet River. At this point, it changes course southwards flowing into West Bengal. The river then goes merging up with the Brahmaputra River after it bifurcates the city of Jalpaiguri and flows just touching Cooch Behar district at Mekhliganj and moves to Fulchori in Bangladesh. Teesta river ultimately drains into Brahmaputra at Teestamukh Ghat in Kamarjani- Bahadurabad in Rangpur district of Bangladesh. Teesta and most of its tributaries are flashy mountain rivers and carry boulders and considerable quantity of sediment. The flow is turbulent and characterised by high velocities.
The Teesta basin in India extends over an area of 9,855 sq.km, which is nearly 0.28% of the total geographical area of the country. The basin lies in the states of Sikkim (72.43%) and West Bengal (27.57%). Teesta is a 414 km long river with total drainage area of 12,540 sq.km,flowing through India and Bangladesh. Teesta basin receives major part of its rainfall during the South-West monsoon period. Rainfall is heavy and well distributed during the months from May to early October. July is the wettest month in most of the places. The intensity of rainfall during South-West monsoon season decreases from South to North, while the distribution of winter rainfall is in the opposite order. Water availability in Teesta basin in India is estimated to be 22.73 BCM which is around 1.14% of the total water availability in the country.