Iraq’s reservoirs: what one wet winter did not fix

More than 70 per cent of Iraq’s inflows come from neighbouring countries, according to its water ministry.² That makes storage the only lever it fully controls. Tigris and Euphrates flows now run about 30 per cent below their 1980 level.¹ In May 2025 the ministry said Iraq was receiving under 40 per cent of its allocated share of the two rivers.³ One AGSI analysis attributes an estimated 56 per cent cut in inflows to Turkey’s dam and irrigation programme in south-eastern Anatolia.⁴

By May 2025 storage had fallen to about 10 billion cubic metres, against the 18 billion the ministry said the summer season should begin with.⁵³ It kept falling. Habbaniyah Lake dropped to 555 million cubic metres, 17 per cent of its capacity. By September 2025 it had stopped discharging to the Euphrates.¹

There was no design: the recovery was weather. The Arab Climate Outlook Forum had given a 50 per cent probability of above-normal rainfall, driven by a weak La Niña and a negative Pacific Decadal Oscillation, and the rains delivered exactly that.¹ The seasonal forecast was actionable and correct, which is worth recording on its own.

Mosul Dam went from 280 million cubic metres at the start of 2026 to almost its full safe operating capacity, and hydropower resumed. Tharthar Lake had hit its lowest satellite-recorded level in October 2025. Diversions of between 1,500 and over 2,500 cubic metres a second have since brought it back to live storage level. Habbaniyah resumed operating.¹

Reserves now cover drinking and household needs for around two years, and perennial orchards are secured for the near term. Wheat reserves cover about 14.5 months, so no nationwide acute food crisis is expected. The risk sits with smallholders and with displaced households outside the public distribution system.¹

Inflows reached the southern marshlands of Dhi Qar, Maysan and Basra. Those support the fishing and pastoral livelihoods of more than four million people, and the United Nations says the recovery may reduce climate-driven displacement in the near term.¹

Capital moved too. Iraq’s power and water sector recorded its largest year of investment on record in 2025, with more than 17 billion dollars in contract awards.⁶ The supply-side answer for the south is now under contract: a one million cubic metre a day desalination plant at Al-Faw with its own 300 MW power plant.⁶ A transmission contract worth 1.32 billion dollars covers about 240 km of pipeline to move that water, though work still depends on preconditions being met.⁷⁸

The United Nations is unusually blunt about its own good news. The recovery covers barely a quarter of what was lost since 2020, and less than a fifth of system capacity. Its published warning is that the window must be used to accelerate reform, not to signal normalcy.¹

Four things undercut the headline. Above-normal temperatures were forecast at 60 per cent probability, so evaporation is eating the gain and storage figures overstate the net hydrological benefit. The recovery is a Tigris recovery: Haditha on the Euphrates remains low, because the inflow from Turkey did not come. Approved summer rice cultivation requests could reverse the season’s storage gains by the next water year, as the ministry itself warns. And groundwater remains critically depleted, which matters most where there is nothing else. In Sinjar and Ba’aj over 75,000 people face shortages, rainfall has fallen 40 per cent in five years, and 15 per cent of residents have already left.¹

The rains also did harm. Flooding killed at least two people in Sulaymaniyah in December 2025, and inundated 300 tents at the Bizibez camp in Anbar on 29 March 2026.¹

The figures themselves are contested, and the gap is not small. The United Nations puts the recovery at about 3.5 to 20 billion cubic metres.¹ Iraq’s Ministry of Water Resources puts it at 5 to 34 billion, and calls the low point the lowest since 1933.⁹¹⁰ In February 2026 the same ministry still classed the situation as a national crisis, and Shafaq put the winter’s gain so far at no more than one billion cubic metres.¹¹ Anyone quoting a single number here should say whose it is.

A wet year is a window rather than a solution. The operative risk is that it reads as normalcy. That is the United Nations position, and it generalises.¹ Pair any storage number in a warming basin with an evaporation-adjusted net, because the gross figure flatters.

Demand-side gains can be given back in a single planting decision.¹ Emergency crop restrictions are politically reversible in a way that infrastructure is not. That is why the rice question outranks most of the capital programme.

The instrument matters as much as the deal. Under the framework with Turkey signed in April 2024, Turkish companies build Iraqi water projects paid for from Iraqi oil sales.¹² The executive mechanism signed in November 2025 added a Turkish commitment to release one billion cubic metres.¹²⁴ As a memorandum of understanding it goes to cabinet rather than parliament. As of April 2026 it still awaited cabinet approval, because a caretaker government could not act on long-term decisions. Winnie Zheng of AGSI ties its success to government formation and the timely implementation of reforms.⁴ Once a new cabinet sat, it capped crude deliveries under the deal in September 2026.¹³

There is a harder lesson underneath. Turkey has urged Iraq to cut losses from leakage, unlined canals and illegal tapping.¹⁴ That makes downstream efficiency a negotiating asset, not only a domestic saving.