After the Uri incident our Prime Minister said, “blood and water cannot flow together.” Now the BJP PM in waiting, Nitin Gadkari, has chipped in by saying India will cut off water to Pakistan. This must be music to the shakha crowd, but it is far from reality.

By implication Gadkari was repeating the old threat that India will retaliate, this time for Pulwama, by turning off the spigots of the three western rivers of the Indus basin that flow unhindered into Pakistan and sustains most of its agriculture and power generation.

The truth is that the flow of blood can be stopped, but water will continue to flow.

The Indus river system has a total drainage area exceeding 11, 165, 000 sq.kms. Its estimated annual flow stands at around 207 km3, making it the twenty-first largest river in the world in terms of annual flow. It is also Pakistan’s sole means of sustenance. The British had constructed a complex canal system to irrigate the Punjab region of Pakistan. Partition left a large part of this infrastructure in Pakistan but the headwork dams remained in India fuelling much insecurity among the Punjabi landowning elite in that country.

The World Bank brokered the IWT between India and Pakistan after many years of intense negotiations to allocate the waters of the Indus river basin. Prime Minister Jawaharlal Nehru and President Ayub Khan signed the treaty in Karachi on September 19, 1960.

According to the IWT, control over the three "eastern" rivers — the Beas, the Ravi and the Sutlej — was given to India, while control over the three "western" rivers — the Indus, the Chenab and the Jhelum — to Pakistan. Since Pakistan's rivers flow through India first, the treaty allowed India to use them for irrigation, transport and power generation, while laying down precise regulations for Indian building projects along the way.

The treaty was a result of Pakistani fears that, since the source rivers of the Indus basin were in India, it could potentially create droughts and famines in Pakistan, especially at times of war. Since the ratification of the treaty in 1960, India and Pakistan have fought three wars, but the flow of water as per the treaty was not hampered even for a single day.

On the face of it the pact is seen as generous to Pakistan as it gives the lower riparian state 80% of the water of the western rivers. But the reality is that IWT makes a virtue of a necessity, as it is the geography of the region that decides this rather than any altruism.

The main Kashmir valley is just a hundred kms wide at its maximum and 15,520.30 km2 in area. While the Himalayas divide the Kashmir valley from Ladakh, the Pir Panjal range, which encloses the valley from the west and the south, separates it from the great plains of northern India. This picturesque and densely settled valley has an average height of 1,850 meters above sea-level but the surrounding Pir Panjal range has an average elevation of 5,000 meters.

Thus the Pir Panjal range stands between the Kashmir valley and the rest of the country and is an insurmountable barrier that precludes the transfer of water anywhere else. And neither do the contours of the Kashmir valley allow for more waters to be stored in any part of it. Since the waters cannot be stored or used by diversion elsewhere it has to keep flowing into Pakistan.

Of the three western rivers “given” to Pakistan, the Indus, which debouches from Indian territory near Kargil and then flows entirely in Pakistan, controlled territory. The Jhelum originates near Verinag near Anantnag and meanders for over 200 kms. in the Kashmir valley before it enters Pakistan occupied Kashmir. After flowing through Srinagar it fills up the Wular Lake and then traverses past Baramulla and Uri into POK. The hydel projects constructed on it supply most of the electricity to the Valley.

The Chenab, also known as the Chandrabhaga, originates in Lahaul Spiti in Himachal Pradesh and flows through the Jammu region into the plains of the Pakistani Punjab. The catchment of the Chenab is elongated and narrow. The catchment area of the Chenab is mostly in India. But the Chenab runs through deep valleys and the river drops by as much as 24 mtrs. per kilometer, imposing physical constraints and huge economic costs on harnessing it.

The three eastern rivers allocated to India by the IWT are the Beas, Ravi and Sutlej. These waters sustain agriculture in Punjab and some extent Haryana and are substantially used. What enters Pakistan is usually just enough to keep the stream flushed. But nevertheless Pakistan has from time to time blamed India for its floods to the sudden and deliberate release of storage gates.

Despite this the IWT has worked exceedingly well for both countries, and both are loathe disturbing it. Even when India and Pakistan went to war in 1965, 1971 and over Kargil in 1999, the waters flowed without interruption. The fact is that the IWT works because it suits both countries by making a virtue of the geography.

The Pulwama incident has fuelled much anger within India and the Modi government which rode to power promising to deter Pakistan origin terrorism in India, by threatening retribution is now hard pressed to deliver. After Uri it discovered that there is a wide yawning gap between promise and reality.

The PM’s pre-election speeches are now being played back to him to taunt him. The Modi government is flailing for options short of the use of arms. Thus, the somewhat exasperated suggestion seemingly made by the Modi regime that it would relook the treaty. It can relook it till kingdom come, but the reality remains the same.

Besides as Dr Shakil Ahmad Romshoo, head of the earth sciences at the geology and geophysics department, University of Kashmir recently said: “Let us assume we stop the water supply for the sake of argument. Where would the water go? We do not have infrastructure to store this water. We have not built dams in J&K where we can store the water. And being a mountainous state, unlike Tamil Nadu or Karnataka, you cannot move water to another state. So you cannot stop the water technically.”

But even if it can be done, climate change is upon us with severe implicit consequences for both countries, but mostly for Pakistan. The Indus river basin is fed mostly by glacier melt, unlike the Ganges and Brahmaputra basins, which are fed mostly by the monsoons.

Since climate change is now affecting the Himalayan glaciers the water patterns in the Indus river basin are already showing changes. Hence Pakistan constantly keeps up a drumbeat of false charges about the non-adherence to the IWT by India. It has only reinforced its determination to seize Jammu and Kashmir in the mistaken belief that it will control the water to its irrigation network. But will there be enough water for very long?

Widely referenced estimates indicate a troubling long-term trend for the flow of the Indus river basin. River water provides 80 percent of all irrigation water for Pakistan’s critical agriculture sector. These water sources are already near their limits, with most water diverted to northern Pakistan’s agricultural regions at the expense of the south. In fact, so much water is diverted from the Indus before it reaches the ocean that seawater has invaded the river channel miles inland.

Based on current projections, the Indus River system is expected to fall below 2000 flow levels between 2030 and 2050. The drop-off is estimated to be most serious between 2030 and 2040, with a new equilibrium flow of 20 percent below that of 2000 reached after 2060.

Not only is Pakistan running out of water, it seems to be soon running out of time. As its founding father poet Allama Iqbal wrote: Watan Ki Fikar Kar Nadan! Musibat Ane Wali Hai/Teri Barbadiyon Ke Mashware Hain Asmanon Mein. (Think of the homeland, O ignorant one! Hard times are coming/ Conspiracies for your destruction are afoot in the heavens.)