Dhaka continues to rely on groundwater for nearly three-quarters of its water supply despite decades of plans to shift to surface water, a dependence experts say is driving a rapid decline in the capital’s groundwater table and threatening its long-term water security.
According to Dhaka WASA, around 74% of the city’s water comes from groundwater, while only 26% is supplied through treated surface water, even though the utility was originally established with the goal of sourcing most of its water from rivers.
An unnamed WASA official told Dhaka Tribune that the capital’s groundwater table has dropped from around 40 meters in 2001 to nearly 109 meters in 2024—an average decline of about three meters annually.
The trend has coincided with a sharp rise in the number of deep tube wells across the city. WASA data shows the number of active deep tube wells increased from 906 in FY2020-21 to 997 in FY2022-23, 1,333 in FY2024-25, and 1,351 in FY2025-26.
Dhaka currently requires around 310 crore liters of water daily, with demand fluctuating between 300 and 315 crore liters. Dhaka WASA supplies water to around 2.5 crore residents through nearly 406,000 household connections.
The utility’s five water treatment plants produce around 90 crore liters of water daily, while approximately 220 crore liters are extracted from 1,351 deep tube wells, underscoring the city’s overwhelming dependence on groundwater.
Md Abdul Kader, deputy chief of Dhaka WASA’s Public Information Division, said each deep tube well produces roughly 1,000 to 3,000 liters of water per minute. In contrast, the number of water treatment plants has remained unchanged at five.
The trend is consistent with findings from a 2021 study, Assessment of Declining Groundwater Levels Due to Excessive Pumping in the Dhaka District of Bangladesh, which found groundwater levels in densely populated parts of Dhaka are declining by 1.5 to 2.11 meters per year, while newly urbanized areas are experiencing annual declines of 1.01 to 1.09 meters. Rural areas recorded comparatively smaller declines.
Historical data also showed groundwater depletion accelerating over successive decades—from 0.17 to 0.6 meters annually during the 1970s, 0.15 to 0.69 meters in the 1980s, 0.56 to 2.26 meters in the 1990s, and 1.24 to 3 meters per year since 2000.
The researchers attributed the trend primarily to unplanned and excessive groundwater extraction, warning that the decline is spreading beyond the city center into surrounding areas.
Groundwater researcher Dr Anwar Zahid warned that continued over-extraction could leave future generations facing severe groundwater shortages.
“The deeper we extract water from, the longer it takes for the aquifer to recharge. Since groundwater levels have already fallen significantly, replenishment will take much more time,” he told Dhaka Tribune.
“We have covered almost the entire city with concrete. There is hardly any exposed soil left for rainwater to infiltrate and naturally recharge groundwater,” he said.
Dr Zahid said Bangladesh is unlikely to experience sinkholes similar to those seen in some other countries because of its predominantly sandy geology. However, he cautioned that the country lacks sufficient research to predict the combined impacts of continued groundwater depletion and major earthquakes.
He also noted that nearly 30% of water is wasted every day, stressing that improving public awareness and reducing misuse could substantially lower demand.
Dr Zahid recommended reducing groundwater extraction, increasing reliance on surface water, and exploring artificial groundwater recharge, a practice already used in several countries.
Professor Emeritus at BRAC University Dr Ainun Nishat said maintaining a balance between surface water and groundwater use is essential.
“Filling ponds and wetlands for urban development reduces natural groundwater recharge and increases long-term risks. A declining groundwater table is not good for the country,” he told Dhaka Tribune.
“WASA is increasingly bringing water from the Padma and other rivers. However, within the next few years, drawing water from the Padma could become increasingly difficult because the river continues to shift westward. The government must therefore develop a long-term, sustainable strategy to secure the city’s future water supply.”
“When the dry season arrives, the easiest response is to install more tube wells. That may solve an immediate crisis, but it does not solve the long-term problem,” he said, calling groundwater depletion a national challenge, as excessive extraction is also occurring for irrigation across the country.
Dhaka WASA Managing Director Mohammad Aminul Islam acknowledged that the falling groundwater table is “very alarming.”
“If everything proceeds as planned, within the next four to five years around 75% to 80% of our water will come from surface sources, while only 20% to 25% will rely on groundwater,” he told Dhaka Tribune.
He said work is underway on Sayedabad Water Treatment Plant Phase III, Padma Water Treatment Plant Phase II, and infrastructure to bring water from the Gandharbpur Water Treatment Plant into the capital.
Regarding private deep tube wells, Aminul said WASA has begun taking action.
Beyond WASA’s own extraction, thousands of privately installed deep tube wells are also drawing groundwater across the capital.
A homeowner in Shewrapara, who requested anonymity, said he installed a private deep tube well two years ago after repeatedly receiving insufficient, dirty, and foul-smelling water through the WASA supply.
“Since installing the tube well, we no longer face water shortages,” he said.
Experts, however, say stronger regulation of groundwater extraction, wider adoption of rainwater harvesting and artificial groundwater recharge, and faster investment in surface water infrastructure are essential to prevent Dhaka’s groundwater reserves from declining faster than they can naturally recover.
