Going awry with the flow

The precariously low water levels at dams managed by the Bhakra Beas Management Board (BBMB; the Bhakra dam on Sutlej River, Pong dam on Beas River and Thein dam on Ravi River) has led the Board to declare that if there are no rains soon, an urgent meeting of several states will have to be called to consider emergency measures.

The signs have been building up for sometime now. Summer in north-west India has already been rather long, hot and dry, and the monsoon has been showing all the signs of being deficient this year. The India Meteorological Department has also said that north-west India may have the worst deficit of all regions of India during this season's rains. But it seems BBMB did not read these early signals early enough, or well enough. Instead, it did not take measures to build up the reservoirs to levels that it could have had, and subsequently allowed them to deplete faster than usual. As a result, we now face a situation that could well have been avoided.

Data from the reservoirs

Let us first take stock of the current situation. The water storage (live storage capacity) on June 27, 2012 (as per the latest available weekly bulletin from the Central Water Commission) was 16 per cent at Bhakra (compared to 37 per cent same date last year), 14 per cent at Pong (54 per cent last year) and 26 per cent at Thein Dam (47 per cent last year). So it is clear that the water storage in all three dams on the same date last year was much higher than what it is this year.

All these reservoirs are on snow-fed rivers, so it should not be surprising to find substantial water storage in these dams at the beginning of the monsoon. Also, rainfall in the catchments of these dams last monsoon was above normal and the reservoirs were almost full at the end of monsoon, say early October 2011. So the lower water levels today are not due to any deficit in last year's monsoon.

So when did the depletion in water storage take place? It seems the situation was comfortable until early February this year, when Bhakra was 58 per cent filled (64 per cent storage previous year), Pong 53 per cent (63 per cent last year) and Thein 35 per cent (41 per cent last year). Over the next two months, however, the depletion set in. The water storage in the three reservoirs reduced by 33 per cent (Bhakra), 23 per cent (Pong) and 16 per cent (Thein), whereas last year, the depletion in the same period was much lower at 25 per cent, 14 per cent and 6 per cent for Bhakra, Pong and Thein respectively. This year, the three reservoirs lost 8-10 per cent more water in these two months than they last year.

Why? In these months of February and March, the residual rabi crop irrigation should not have been much higher than last year. And post rabi, in summer season, irrigation should anyway be discouraged and dis-incentivised. Punjab and Haryana has actually passed laws that say that before June 10 and 15 respectively, no paddy transplantation should be allowed.

This depletion is further corroborated when we look at the water release figures from the Bhakra and Pong dams, available on the BBMB's web site. We find that the average water releases from both the dams in the January-March period this year were unprecedented: the highest in the last 13 years for which the figures are available online. In the case of Pong dam, the average release even during April-May this year was higher than the figures for the last two years. Clearly, there was extra-ordinary water depletion in the dams in Feb and March and even beyond this year in these reservoirs.

Why? Only BBMB officials can help unravel this, but there is no doubt that very high levels of discharge from the dams took place throughout the first half of this year.

Power versus water?

Some government sources have been speaking of less inflow into these reservoirs this year. That appears to be true, judging by the power generation at the upstream hydropower station of Nathpa Jakhri. This project does not have substantial storage capacity, therefore most of the inflow in the river during the months of January to June would get reflected in the power generation figures. We find from the power generation figures for this project available on the website of Central Electricity Authority that this station generated 2719.03 million units (MU) power in the first six months of this year, about 19.5 per cent lower than the power generated during the same period last year.

But the BBMB didn't adjust the release of water from its dams while the inflow decreased. At the BBMB-managed dams themselves, the power generated during the same six months this year was only 1.5 per cent below that in the last year. The BBMB was releasing more water, even while its inflows were about 20 per cent lower than that in the last year.

By early April this year, the water levels in all three BBMB reservoirs had significantly depleted. However, after early April, when irrigation releases should have been very low and when these reservoirs continue to get significant inflows due to snow melt, there was a chance for BBMB to increase the water levels in the reservoirs. However, the BBMB did not do this. On the contrary, the level at Bhakra further reduced from 25 per cent of live storage capacity in early April to 16 per cent by June 27. In this period, BBMB continued to produce power at roughly the same levels as last year, rather than hold the water.

There is certainly a balance to be maintained between power production and water storage, but as the BBMB approaches what it calls an emergency situation, it bears asking whether it was prudent enough in drawing this fine line.

There are a number of good reasons why the BBMB should have prioritised water storage. A number of official monsoon forecasts were available in April 2012 itself, which said that monsoon in north-west India is likely to be below the long-term normal level. For example, the South Asia Climate Outlook Forum conference (in which IMD and the Indian Institute of Tropical Meteorology also participated in April) suggested that the probability of north-west India getting below-normal rainfall was 40 per cent, which was the highest for below normal rainfall forecast among all the areas.

Seeing this, BBMB should have immediately adjusted its reservoir operation and started building water storage in its reservoirs, which were already very low. But it did not do so, and instead allowed higher outflows than there were inflows (as is apparent from its power generation figures), thus further depleting the reservoir levels.

The likely consequence of this is that farmers and people throughout north-west India will suffer due to the unresponsive reservoir operation by the BBMB - quite similar to what happened in 2004 and 2009. Had BBMB's reservoir operation been more responsive to the developing situation, the situation at BBMB reservoirs today need not have been so critically now.

India has no transparent, participatory and accountable reservoir operation policy. The reservoir management entities have no clear policy matrix with goals that they try to achieve through the management of water flows. As a result, the errors are thus learned and re-learned each time the rains deviate significantly from the average. This has to change - it is high time that the Governments of India and the States develop a more responsible, transparent, participatory and accountable reservoir operation policy, with attendant rules and norms. Until that happens, people will continue to suffer needlessly, from the mistakes of some individuals who can't even be held accountable.

Climate change has now become an irrefutable fact, and reservoir operations need to be more flexible and responsive to weather predictions, be they about low rainfall or high rainfall. Dam operators cannot simply neglect these predictions, but should develop strategies to cope with them.