Can the Padma Barrage work without a water deal?

The government has approved the Padma Barrage in the confidence that engineering can outpace geopolitics. It is a bold, expensive, and politically attractive undertaking – one that promises to revive dying rivers, push back salinity, stabilise the southwest, and restore the ecological pulse of a stressed delta.

But Bangladesh is preparing to spend Tk50,000 crore – the equivalent of a Dhaka Metro-sized investment – on a hydraulic system whose dry-season performance depends on a variable it does not control: India's upstream releases at Farakka.

With the Ganges Water Sharing Treaty expiring in 2026, Bangladesh is effectively building a world-class regulator at the tail of a river whose lean-season flow is governed by another sovereign. That is strategic exposure disguised as infrastructure.

The barrage responds to a real and long-standing problem. Decades of diminished lean-season flow linked to Farakka have transformed the Padma into a river of two extremes: a monsoon torrent and a dry-season whisper.

The Gorai, once the southwest's arterial lifeline, receives virtually no meaningful flow during the lean months. Salinity continues to creep deeper into Khulna, Bagerhat, and Satkhira. The freshwater balance of the Sundarbans is steadily weakening.

The proposed barrage promises to reverse this by storing nearly three billion cubic metres of water and redistributing it across a vast deltaic network. But that promise rests on a politically unguaranteed hydrological assumption: that India will release enough water for Bangladesh to store in the first place.

This is where engineering collides with diplomacy.

Infographics: TBS

A barrage can regulate, store, and reroute water. It cannot summon water that does not arrive. The feasibility studies implicitly assume a certain level of dry-season inflow at Pangsha. Yet those assumptions are not anchored in any renewed treaty, transparent monitoring system, or enforceable release schedule.

The fiscal logic is equally unforgiving. In a tight macroeconomic environment, committing this scale of public resources to an asset whose core input is controlled by another sovereign is a high-risk bet. If dry-season flows fall below the assumptions embedded in the design, the barrage risks becoming a stranded asset: impressive on paper and photogenic in drone footage, but unable to deliver the irrigation, salinity control, ecological restoration, or hydropower that justified its cost.

Bangladesh would essentially have built a magnificent valve at the end of an uncertain pipe.

None of this means the barrage should be abandoned. But it does mean the sequencing must be more strategic.

The flow assumptions underlying the project should be made public and stress-tested under lower-flow scenarios. The decision to build should strengthen Bangladesh's diplomatic leverage, not substitute for diplomacy itself. Any renewed Ganges agreement should include joint monitoring, transparent data-sharing, and dispute-resolution mechanisms that directly connect treaty implementation with barrage operations.

The technical design and the diplomatic strategy must therefore be treated as a single policy complex, not as two separate files – one sitting in ECNEC, the other in the foreign ministry.

Prudence demands that the project be examined through at least three lenses.

The first is hydrological prudence. The barrage's benefits are highly sensitive to dry-season inflows. If upstream releases consistently fall below the flow projections used in the feasibility studies, the project could end up managing scarcity rather than restoring abundance. That makes transparent assumptions and stress-testing not a technical luxury, but a policy necessity.

The second is bargaining-power prudence. Once Bangladesh commits to a multi-phase project whose viability depends on Ganges water, its fallback position in future talks weakens. Delhi will know that Dhaka has tied political credibility to infrastructure dependent on upstream cooperation. That is not the strongest position from which to negotiate a post-2026 water-sharing arrangement when the counterparty controls the chokepoint.

A country that has already sunk billions into a downstream regulator is a country negotiating with part of its leverage already spent.

The third is fiscal prudence. In the current macroeconomic climate, the risks are not abstract. A project of this scale creates long-term fiscal obligations regardless of whether its projected returns fully materialise. If performance falls short, the public cost remains while the economic gains diminish.

A barrage without a treaty is a strategy with half its logic missing.

In the end, the country must decide whether it wants a monument to national ambition or a functioning water-management system. The difference lies not in concrete and steel, but in whether Bangladesh can secure the upstream cooperation that makes the project viable.

Otherwise, the project risks becoming an expensive reminder that engineering cannot compensate for unresolved geopolitics.

Zahid Hussain is a former lead economist of The World Bank, Dhaka Office