Being a lower riparian country, Bangladesh is keen on sharing waters of common rivers

West Bengal Chief Minister Mamata Banerjee staying away from Prime Minister Manmohan Singh's delegation to Bangladesh will not only jeopardise the agreement on the sharing of Teesta waters but also cast its shadow on the pact on the Feni river if Dhaka links the signing of the Teesta pact with the Feni.

Till late night on Monday efforts were on to work on the Teesta treaty, which came undone after Ms. Banerjee, who had reservations about the proposed water-sharing formula, decided not to accompany the Prime Minister. The pacts on sharing the waters of the Teesta and the Feni are to be 15-year interim agreements for lean periods between October and April, until firmed up data is collected through joint hydrological observation. The setting up of observation stations is also part of the pacts.

Being a lower riparian, Bangladesh is keen on sharing waters of common rivers and, after the Ganga Water Treaty of 1996, accorded the highest priority to the sharing of Teesta waters. The other rivers earmarked for sharing in the first phase are the Manu, the Khowai, the Gumti, the Muhuri, the Jaldhaka (Dharia) and the Torsa (Dudhkumar). The Feni was included in 2005 at the 36{+t}{+h} meeting of the Joint River Commission in Dhaka..

The Teesta originates in Sikkim near the Panhunri glaciers and, after traversing about 150 km in the hills, it debouches into the plains of West Bengal. Flowing a further 120 km in West Bengal, it crosses the international boundary into Bangladesh and finally meets the Brahmaputra at Teestamukh, the confluence point.

The river drains 12,729 sq.km up to its confluence with the Brahmaputra, of which 83 per cent of the catchment lies in the Indian side and 17 per cent is in Bangladesh. India has constructed a barrage at Gazaldoba for feeding its canals. Bangladesh has built a barrage at Dalia for diverting waters to its canals for irrigation. While there is no dearth of water during monsoon, there is shortage during the lean period for which an agreement on sharing is being worked out.

The agreement has to take into account minor irrigation and drinking water needs of Sikkim and West Bengal, while Bangladesh has sought a lean-period flow for purposes of drinking water, irrigation, industrial use, navigation and environment.

In July, 1983, both sides reached an understanding on an ad hoc sharing of the Teesta flows during the lean period with an allocation of 36 per cent for Bangladesh and 39 per cent for India, leaving 25 per cent to be decided later. However, this has remained unimplemented for differences over the data of water flows.

Both sides are now striving to arrive at an agreement on catchment area flows in the lean season, after taking into account changes due to climate, as well an understanding on water flow data.

The Feni originates in Tripura and makes a common border of 87 km with Bangladesh. After traversing 90 km in Tripura, it flows into Bangladesh. Being a border river with one side of the banks in India and the other in Bangladesh, no activity is allowed in 150 yards from the centre of the river.

Both sides want to lift waters of the Feni for irrigation and are said to have agreed on sharing in equal quantities in the pact that has been worked out.

Both countries also agreed at the Secretary-level talks in 2010 on bank protection at 50 sites of common smaller rivers on their respective sides with a time frame of three years.