In early Kharif this year, the Chenab did not behave like a river. At Marala, flows rose sharply, then fell just as abruptly, only to rise again without warning. There was no corresponding rainfall pattern, no snowmelt signal sufficient to explain the volatility. For irrigation managers and farmers in Punjab, the problem was immediate: water arrived, but not when it was needed.

In an irrigation system built on predictability, timing is everything. Land preparation, sowing, and early irrigation depend on stable canal supplies within a narrow seasonal window. Even short-lived disruptions delay germination, force farmers onto tubewells drawing from already stressed aquifers, and compress planting schedules in ways that affect the entire season’s output. A river that delivers its allocation at the wrong time behaves, for all practical purposes, like a reduced river.

For 65 years, the debate over the Indus Waters Treaty has been framed in terms of ownership: who gets how much water, from which rivers. That question was settled in 1960 by dividing the system. What the Chenab is now showing is that the problem has changed. The issue is no longer only how much water flows downstream, but when it arrives and who controls that timing.

The record at Marala is unusually clear. Hourly discharge data for April and the first week of May shows a sequence of sharp surges followed by sustained depressions and rapid declines. Flows rose from baseline levels into pronounced peaks, then settled into depressed bands for over a week, before rising again and falling by more than half within hours. This pattern repeated within a span of weeks, without any rainfall in the catchment sufficient to explain it.

One such episode might be attributed to routine reservoir operations. Two in immediate succession is a behavioural signature. The Chenab did not respond like a river reacting to weather. It behaved like a system being........

© The Nation