By Nilanjan Ghosh
Lately, there has been quite a bit of hue and cry over the sharing of the Teesta river water between Bangladesh and India. Bangladesh wants 50 percent of the Teesta waters during the dry season — from December to May. Substantially low flow has affected farmers in Bangladesh whose standing paddy crops are withering away and also fishermen who are facing loss of livelihoods. While the Prime Ministers of the Bangladesh and India are inclined to sign a treaty over the sharing of the Teesta waters, the Chief Minister of West Bengal offers an alternate proposal of providing water from three different North Bengal rivers, namely, Torsa, Raidak, and Jaldhaka. The West Bengal CM’s position is based on the premise that there is not adequate water in the Teesta to be shared. This is vindicated by excerpts (published in an article in thethirdpole.net on April 14, 2017) of a recently prepared internal report on the Teesta prepared by an Expert Committee of West Bengal Government.
Wrong measures or hidden facts?
The excerpt goes in this fashion: “Two barrages on Teesta, at about 100 km from each other, in India and Bangladesh were planned to cater [to] irrigation in more than 16 lakh [1.6 million] hectares of land together; around 9.2 lakh [920,000] hectares in [the] state of West Bengal in India and 7.5 lakh [750,000] hectares in Bangladesh. According to a rough calculation, such a scale of irrigation for boro crop (dry season paddy) will require around 1600 cumec (cubic metre per second) of water; while through much of the dry period the river hardly has 100 cumec of water, i.e. one sixteenth of total water requirement in [the] two countries.”
This statement as given in the excerpt does not conform to scientific knowledge of river science and agronomic arithmetic. While considering crop-water requirements and existing cropping patterns, one needs volumetric measures to reach at numerical figures on water requirements. Weird as it may seem, the measurements in the excerpt are given in “cumec” or “cubic metre per second”, which is essentially the unit of flow in the channel, and not volume. As an ecological economist and river analyst, I am yet to come across any literature globally that talk of estimation of the hectares of irrigated land on the basis of flow measures, and without volumetric measures. This brings to the fore quite an extremely important concern: how far is this data reliable? What is the source of such an estimate?
Further, if this figure is to be believed, the obvious question that arises is: where has the remaining 94% of the water gone? In some writings lately, the Teesta Barrage Project (TBP) at Gajoldoba in the Jalpaiguri district of West Bengal has been blamed for the disappearing waters further downstream. Conceived as a multi-purpose project in the aftermath of the massive floods in Jalpaiguri in 1968, the TBP was planned for flood control, hydropower and irrigation in north Bengal. It is proclaimed that though the TBP has contributed to flood control to an extent, there has been much less success towards increasing the areas under irrigation in the lower command area and the flow in the downstream nation of Bangladesh has diminished. It has been hypothesized that water diversion through the Teesta-Mahananda irrigation canal is responsible for the flow reduction.
Unfortunately, all these claims and counter-claims stand as mere hypothetical conjectures in a water governance regime that is marked by lack of analysed data. Neither has any government placed any data in the public domain for independent professionals to take up research and work on them. There is no water accounting, sediment budgeting, or a simple hydrograph of the Teesta in the public forum.
Arithmetic hydrological thinking
When the TBP was thought of as a multipurpose project, what was not thought of was the important role of storage for allocation during the dry season. The concerns of sedimentation were not taken into account. Flood control seems to have been thought of more from the perspective of channelising “surplus” water through alternate link canals. The concerns of downstream ecosystem services, the linkages with livelihoods, and aquatic biodiversity never featured in the scheme of plans. This reductionist thinking with simple average per capita water availability was the core of this “arithmetic hydrology” that conceived of water as a stock of resource to be used for human consumption and use. The 1983 and unsigned 2011 agreements bear ample testimonies of this thinking, given that there are attempts to use up the entire water without any recognition of ecosystem.
The situation has not changed today. The conflict today is still prevalent with pure agricultural use of water, and that too for the production of the boro or dry season rice of the region. It is well-known that paddy is the most water-consuming crop with a crop-water requirement of around 1800-2800 mm. Yet, there has been no attempt on the parts of government machineries to counsel producers to diversify to other less water-consuming crops over the last 30 years, ever since the talks on Teesta emerged between the two nations. Rather, over time in India, the minimum support price of paddy has been increased by leaps and bounds vis-à-vis the less water-consuming staples, which in turn also led to a rise in market price of paddy, thereby incentivising producers to shift more acreage towards paddy, more so during dry seasons. This was further facilitated by development of irrigation facilities through hydrological interventions on the river flow regimes, leading to loss of river health, downstream flows, and ecosystem functions and services.
On the other hand, the West Bengal CM’s recent proposal of providing water through Torsa, Raidak, and Jaldhaka also seem questionable from hydrological, ecological and economic perspectives. Does the dry season hydrograph of the three rivers at least sum up to the dry season hydrograph of Teesta? The three rivers seem to be mere rivulets, as compared to Teesta, and their flows might not apparently match up with Teesta. Of course, we need better data to come up with more concrete inferences. The possibility that I see here is in the form of constructing link canals between the three rivers and a storage mechanism to store water during monsoon and make them flow during dry season. This not only has its capital costs, socio-economic costs, but more clearly ecological costs that may even impede on long-term livelihood issues.
On the other hand, there is already a proposal of Manas–Sankosh–Teesta interlinking under the national water transfer project and necessary quantity of water may be given to Bangladesh by diverting water from Manas and Sankosh through link canal to Teesta. There is an additional proposal of linking the Teesta to the Farakka under the same water transfer project. The so-called “surplus” water (as is defined in the reductionist engineering paradigm) from Manas and Sankosh can flow to Teesta, and then to Farakka! So, during dry months, Bangladesh can be given water through Teesta, and even the Bangladeshi allegation of low flows in the mainstream of the Ganges through Farakka can also be resolved with this “additional” water! Apparently, this might seem to be a low-hanging fruit to all political entities concerned.
But, the problems will only further compound with this scheme. First, Manas and Sankosh are significant tributaries of the Brahmaputra-Jamuna river system in India and Bangladesh, and diverting the waters from these two rivers will reduce flow in the mainstream of the river, thereby significantly affecting downstream river-bed agriculture, ecosystem, and aquatic biodiversity. Second, as has often been floated around, the Manas-Sankosh link canal may pass through protected areas, which can create significant problems for species movement and terrestrial breeding behaviour. Third, the issue of techno-ecological-economic feasibility of such a scheme is not yet clear. Fourth, the possible reduction in flows through the Jamuna channel in Bangladesh is likely to result in another transboundary water dispute, about which Bangladesh has already expressed apprehension.
Need for independent and objective analyses
There is no doubt that the Bangladesh-India water issue is just getting more and more compounded with the Teesta, which not only has hydro-political implications but also implications for geopolitical relations between two nations, and the internal politics of Bangladesh. More so, because of unanswered questions raised in this article! There is an uncanny suspicion and apprehension on parts of governments about objective and independent analyses about rivers, especially those crossing international boundaries. That is precisely why most data related to flows, sediment, stocks, etc. have been classified. But, objective scientific knowledge could have informed so much as to reach a resolution. The leeway from the present impasse essentially lies in “answering the unanswered”, and then moving towards a right form of institutional mechanisms like the basin-level organisations with authoritative powers.