PAKISTAN’s water situation is becoming grimmer by the day. This year, dams filling, or near filling, and start of their depletion only indicates threats to the country’s water economy and its agriculture.

Tarbela Dam got filled on August 20 and its drawdown started the very next day. The Mangla Dam got stuck 10 feet below the optimum level and started going down before filling. Barring any unusual celestial intervention, which is not on metrological radar yet, both lakes’ levels would continue sliding — making sowing more difficult the next rabi season.

The behaviour of the rivers is worrisome. By the time both lakes got to their maximum level for the year, all rivers suffered significant reduction in their base flow — leading to drawing of water from the dams to save the standing kharif crops.

The pace of reduction in rivers’ base flow was even more surprising. Within 48 hours (between August 18 and August 20), river Indus came down to 145,000 cusecs from 218,600 cusecs. River Kabul dipped from 51,200 cusecs to 30,700 cusecs. River Jehlum came down from 33,500 cusecs to 23,700 cusecs and Chenab from 58,200 cusecs to 46,300 cusecs. Ever since, they have not recovered to their normal historical flow during this period of the year.

This year, the water situation points to another emerging dimension of the problem; crisis can hit right in the middle of the monsoon season, while the country is losing its manoeuvring space

The worst is the sudden, erratic flows of the river Indus throughout the year. By August 20, it produced only 34 million acre feet (MAF) water against its normal production of 41maf — a deficit of seven million acre feet. Despite this deficit, three million acre feet had to be sent downstream Kotri barrage because the dam filling criteria restrict storage of water to one foot a day after the lake achieves a certain level.

The rivers’ combined water flow dipped below the provincial indents at that point of time. The Indus River System Authority (Irsa) wrote to provinces to either cut their existing demands or be prepared for huge Rabi shortages. The provinces, resorting to the time-tested wisdom of saving what was already sown, told Irsa to start depleting dams rather than forcing them to cut demands, and the Irsa complied — because water belongs to the provinces.

This year, water situation now points to another emerging dimension of the problem; crisis can hit right in the middle of the monsoon season, while the country is losing its maneuvering space — the reservoirs. Earlier, the country was facing problem at the end of rabi season when dam started hitting the dead levels earlier. Their time of eating into the reserves started on the eve of the rabi season (read wheat — the staple — maturity season).

Starting from June, the time they used to last when built, they started hitting dead level earlier. Currently, both dams have started hitting dead level in February because the silt has eaten around 30pc of their storage capacity. With the rising of the Mangla Dam by 30 feet, the country has achieved a cushion of 2.88maf, but the Tarbella continues to suffer from silt invasion. This year, its dead level was raised by two feet because more silt has moved into it during the last few years.

Third dimension is added by the series of structures that the Indians are building on rivers belonging to Pakistan under the Indus Water Basin Treaty. The world has warned both India and Pakistan that once those structures are in place, the Indians would be in a position to at least disturb the flow of water, if not its quantum.

All these processes — early depletion of dams, unpredictable, and erratic behaviour of the rivers and the Indian construction — are bound to continue, and worsen with water shortage.

Pakistan needs to have a comprehensive look at its water requirements, changing weather patterns and India’s ability to hamper the water flow and firm-up its responses and plan accordingly. One possible way to deal with them is building more dams, wherever possible. Fortunately, all possible dam sites are already identified. It is time to put their construction in a time-frame and start sparing resources for them on emergency basis.

Published in Dawn, Economic & Business, September 1st, 2014