Dhaka faces two water crises at the same time: underground, Dhaka's groundwater is running out; on the surface, rainwater has nowhere to drain to.
In the dry season, Dhaka struggles to supply enough water for its growing population. When the monsoon arrives, just a few hours of heavy rain can halt traffic, flood homes and businesses, disrupt supply chains, and put millions at risk. One crisis stems from too little water; the other from too much. Yet we treat them as if they are unrelated.
We need to change that way of thinking.
The government's new Tk 32,554 crore plan to build five reservoirs around Dhaka is a big step in water policy. This plan aims to cut reliance on groundwater by storing and treating surface water, and it also encourages rainwater harvesting and better climate resilience. It warrants serious attention because it finally recognises what experts have warned about for years: Dhaka cannot keep pumping water from underground forever. Right now, the city needs about 3.13 billion litres of water every day, and about 77 per cent still comes from deep tube wells. Groundwater is dropping by two to three metres each year, and demand is expected to rise a lot in the future.
But this reservoir plan also raises a bigger question: If Bangladesh is preparing for water shortages, why are we not equally ambitious about handling too much water?
Every monsoon, Dhaka faces the same problems. Roads flood. Public transport barely moves. Most of the CNG auto-rickshaws halt due to short circuits. Office-goers get stuck for hours. Emergency services have trouble reaching their destinations. Businesses lose customers, factories receive supplies late, and deliveries are cancelled. Each time rain overwhelms the drainage system, the city pays a high economic cost.
People often see waterlogging as just an inconvenience. It silently reduces the city's productivity.
Each flooded intersection means lost working hours. When business areas are underwater, business slows. Damaged roads lead to higher repair costs later. Pools of standing water increase health risks, from mosquito-borne diseases to contaminated floodwater. For Bangladesh's main business city, these repeated losses are not just city problems-they are economic risks.
The issue is no longer just about blocked drains.
Dhaka has grown much larger than its old infrastructure can handle. Wetlands have been filled in, canals have been narrowed, floodplains have been built over, and open spaces have been turned into concrete. Water that used to soak into the ground now runs quickly over paved areas, with nowhere to go. Climate change makes things worse by causing more frequent heavy rains that the drainage system cannot handle.
Cleaning drains before each rainy season is still necessary, but it is now just basic maintenance rather than a real strategy. The city now needs a new vision, one that treats water as a year-round planning issue rather than a seasonal emergency.
Dhaka should consider using a Dual Water Strategy.
The first part is water security. This includes planned reservoirs, rainwater harvesting, wastewater reuse, river protection, and reduced groundwater use. The goal is to ensure the city has enough water when rainfall is low and demand is high.
The second part is stormwater resilience. This requires investing just as much in restoring canals, saving wetlands and flood areas, upgrading pumping stations, adding digital flood-monitoring systems, and, when it makes sense, building underground stormwater tunnels and reservoirs under key city areas and public spaces.
One approach is to store water-the other is to move water away. Both are needed for success. Many cities around the world already use this combined approach.
Tokyo protects millions of people with one of the world's largest underground flood-control systems, preventing excess water from entering the city before rivers overflow. Kuala Lumpur's SMART Tunnel is known worldwide for combining transport and flood control. I have experienced the same in Langkawi. Singapore has shown that reservoirs, drainage, wetlands, and city planning can all work together as one water system instead of separate projects.
Dhaka should not try to copy these cities exactly, as its geography, rivers, and city layout are unique. However, their experience offers one key lesson: strong cities manage water as a whole system, not as separate projects.
Bangladesh already has the skills to build major infrastructure. The Padma Bridge, metro rail, and elevated expressways demonstrate that large national projects are possible. We are now building an underground metro rail. Hence, climate resilience requires the same level of commitment and engineering quality.
Good governance is equally important. Currently, different agencies handle water supply, drainage, canals, roads, and city planning. But water does not respect these boundaries. A coordinated city-wide water plan, with shared data, joint planning, and clear responsibility, would be far more effective than separate efforts.
The new reservoir plan is a good start, but it should not be the end goal. It should be the foundation for a broader city water policy that prepares Dhaka for both droughts and floods.
Cities are usually judged by how well they move people. With climate change, we should also judge them by how effectively they manage water.
Dhaka's next big step in infrastructure should not be about how many kilometres of metro rail or expressways it builds. It should be about something more basic: can the city save water when it is scarce and move it quickly when it is dangerous? Dhaka will become a truly resilient capital for the twenty-first century only when it can handle both challenges.
