Three Nations, One River: A Water Treaty Is Tested by Drought

The treaty was signed in a wetter era. It divided the river’s flow among three nations with the confidence of people who assumed the river would always have flow to divide. This year, for the third time in five, it does not.

The river is running at a fraction of its historical average, drained by a drought that has settled in and shows no sign of lifting. The treaty’s formulas, written for abundance, now have to allocate scarcity — and scarcity is where agreements go to die. Upstream, where the water enters first, there is pressure to hold more back. Downstream, where farms and cities depend on what arrives, there is alarm.

So far the agreement is bending rather than breaking. Diplomats have met in emergency session and agreed to temporary cuts shared, more or less, in proportion. Engineers are racing to wring efficiency from irrigation systems that waste more than they should. The mutual interest in avoiding a worse outcome — open conflict over water is no one’s preferred ending — has held the parties at the table.

But the strain is structural, not seasonal. The climate that the treaty assumed is gone, and the one replacing it offers less water more erratically. Every shared river in a drying region faces the same arithmetic: agreements built for one climate, enforced in another.

The drafters of this treaty are mostly gone. Their successors are discovering that the hard part of sharing a river is not dividing what is plentiful. It is dividing what is not.