The future of Dhaka's water

Ritu Moni, a 12-year-old girl, clutches not just two, but four overly used yellowish 5-litre bottles. She was waiting in a long line with around 20-25 women for water from the deep tube-well of a house in Mohammadpur's Kaderabad Housing Society. Every day from 5 pm to 9 pm, people of this vicinity collect water from this house.

When asked how she will manage to carry all that water home, her answer is a telling sign of Dhaka's growing water woes: "More people from my home are coming to take these back to the house." 

This scene is a daily reality for many in Dhaka with a burgeoning population. Estimates suggest Dhaka welcomes roughly 400,000 new residents every year. This rapid urbanisation, coupled with rising temperatures and a declining water table (surface water), is pushing Dhaka's water resources to a breaking point.     

Two decades ago, I emphasised the need to prioritise drinking water for humans alongside agricultural needs. The authorities did not pay any heed. Now I predict that in 30 years, the Buriganga River's water will become saline, and we must prepare for that eventuality.

Ainun Nishat, water resource and climate change specialist

The piped water supply in many homes, like that of Rabya Akter's, is insufficient. The 35-year-old resident said, "The water line doesn't dispense enough water. Water from here [the deep well] is directly drinkable, so we come here." 

With scorching heat driving water consumption up – Rabya's family of five needs 15 litres a day – residents are forced to find alternative sources.

While some, like Rabya, queue for water from private deep wells, others turn to Dhaka's 290 water ATM booths. However, this option comes with its own set of challenges: long lines and the arduous task of transporting heavy water bottles.

Tap-to-drink water has been a dream and a long-standing demand of Dhaka dwellers, but it seems to be only a mirage. For those who can afford it, bottled water offers another solution, but it can be a significant financial burden. Boiling water becomes the last resort but that also comes with a price. 

According to BRAC research in 2020, the total cost of gas for boiling drinking water in Dhaka city amounts to around Tk170 crore per year. This number must have gone higher by now.

Every morning, Bashabo residents stand in a long queue to collect water. Photo: Mehedi Hasan

Water demand soars higher

AKM Shahid Uddin, Deputy Managing Director of DWASA, told TBS that this year water consumption has surpassed typical levels of summer season consumption as people are taking multiple showers and consuming more water to cope with the excessive heat.

"Usually in hot weather, we need 250-260 million litres of water per day. But this year it was over 280 million litres. And maximum capacity in our production was around 285 million litres," he added.

According to the latest WASA report, the average demand for water in Dhaka is about 265 to 270 million litres per day, while DWASA can produce around 275 million litres per day.

While demand has not surpassed capacity yet, some areas are experiencing water supply disruptions solely because of the sudden increase in usage, officials said. 

As the population is growing pretty fast, the demand will surpass the maximum capacity in no time. Shahid Uddin reiterated that sustaining maximum production is becoming increasingly challenging due to a drop in the water level. 

"Besides, the heatwave rapidly affects our pumps, needing frequent stops to allow them to cool down," he added.

When asked if DWASA can increase water production in response to even higher demand, Shahid Uddin said expanding production with current water sources is not feasible. "We would need to establish new wells but this is hindered by the lack of available land," he said.

The Dhaka Environmentally Sustainable Water Supply Project received $135 million in financing from the Asian Development Bank in 2022.

The project aimed to improve access to and quality of inclusive water supply services and promote environmentally sustainable surface water supply in Dhaka.

The project's objectives also included lowering non revenue water, transiting to surface water sources, rationalising tariffs and protecting water intake rivers. 

In addition, funds were supposed to support the empowerment of women and vulnerable groups to offer more efficient water services. However, the experts are not convinced that any of the promises were fulfilled.

What lies ahead?

Simply put, Dhaka faces a perfect storm: A growing population, rising temperatures, a falling water level and limited options for clean, accessible drinking water. Add more urbanisation 10 years down the line, experts are concerned about Dhaka's water future. 

Sharif Jamil, founder of Waterkeepers Bangladesh (an organisation working to protect the water and water bodies), said, "Because of the climate change-driven calamities, people migrate to the capital in search of a livelihood, further contributing to the urban growth." 

This will further increase water demand. 

Additionally, "With time, the weather pattern will be more erratic [caused by climate change]," said Asif Zaman, Managing Director, Esolve International (infrastructure and environmental services company). 

This will further strain water resources. 

The Water Supply Master Plan for Dhaka City, finalised in 2014, projects the water demand to reach 5,400 million litres per day (MLD) by 2035 with the required production capacity at approximately 6,000 MLD. 

To meet this demand, Dhaka Water Supply and Sewerage Authority (WASA) plans to expand its service area and implement effective demand management strategies. However, the city's unplanned urbanisation coupled with the polluted rivers complicates these efforts. 

Before gauging Dhaka's future water crisis, first, let's see how we got here. 

Young girls collecting water from one of the 290 water ATM booths in the capital. This was taken in Green Road last year. Photo: Rajib Dhar

A brief history 

In 1947, Dhaka had a population of around 200,000 to 300,000 people. For the small population, refined water was effortlessly provided from the Buriganga River at Chandni Ghat, located behind Chawk Bazar. 

However, by 1972, the population had surged to 750,000, significantly increasing water demand. It became evident that Chandni Ghat could not meet the water needs of the growing population. 

In response, the government started setting up tube-wells to quickly access groundwater. The number of tube-wells increased and Dhaka WASA was given authority over the water supply. 

In 1996, WASA was made an autonomous for-profit body. Sayedabad Water Treatment Plant was also established in 2002 and has since been extended to a third phase.

Despite these efforts, it became clear that such measures were insufficient. Meanwhile, Chandni Ghat was completely shut down because the Buriganga River's water had become too polluted to refine. 

"The Sayedabad plant's treatment standards also fell short, particularly in checking for harmful contaminants like chromium from tanneries and mercury from industrial areas such as Tejgaon," said environmental activist Sharif Jamil. 

Consequently, deepwater sources, which were initially at 5-8 feet, are now being tapped at depths of 160 feet – even this is proving inadequate due to poor water recharge.

Deep, deeper, deepest

If groundwater is extracted in the city without commensurate recharge, it depletes. Because of climate change, "the weather will go extreme; the dry season will go extremely dry and the rainy season will be inundated with rain," said environmental specialist Asif Zaman. Both lack of rain, or flood make recharge more difficult.

Sharif Jamil added, "Dhaka, in particular, requires more intensive attention and preparation because the city has evolved in an unplanned manner."

The predicted growth of Dhaka is exceeding expectations due to climate-induced migration and our centralised governing system. Climate-induced migration follows the push-and-pull effect. 

For example, because of Cyclone Remal, many people lost their homes. If they have relatives or friends in Dhaka, those friends will pull them to Dhaka, accelerating the city's population growth.

Since Dhaka's vast land is blocked with asphalt and concrete, it makes recharge difficult and causes water runoff. Additionally, most of the city's small water bodies have been filled. 

As a result, our groundwater level drops 2-3 metres each year. In the early 1970s, we could access water six metres down. 

According to a 2019 study on groundwater sustainability in Dhaka, the average depth (below ground level) of the groundwater table was about 78 metres, which may sink down to 132 metres in the next 10-12 years. This will likely have a substantial impact. 

If current trends continue, it is projected that by 2050, the static water level in Dhaka will decline by an average of 161 metres. This substantial decrease in groundwater levels could render some tube-wells non-operational due to the inability to extract water.

Historically, water from northern aquifers and adjacent peri-urban areas used to recharge the city's groundwater but these sources are also now experiencing significant declines.

The installation of deepwells must follow specific regulations regarding the spacing between them to prevent drawdown and rapid depletion of groundwater in concentrated areas. 

Building construction laws were enacted in 2006 but they are not practically implemented. Many households, both legally and illegally, have installed deep tube-wells, exacerbating the problem.

Photo: Mehedi Hasan

For Dhaka's survival, there is a plan to turn to surface water. Water is coming from the Shitalakshya River, and efforts are being made to bring water from the Meghna River to lessen reliance on groundwater. However, "our plans remain just plans," said Sharif Jamil.

He thinks that this water crisis and Dhaka's waterlogging during the monsoon can both be addressed by reviving retention ponds. This will reduce waterlogging and recharge the groundwater.

If we can open enough water bodies, Dhaka's riverine network also may have more potential. Hatirjheel can be connected to Banani and then extended to Uttara. Many water-based communication routes are possible, which can also alleviate Dhaka's traffic. This way, we can achieve multiple benefits with one solution.

Inamul Haque, Chairman of the Institute of Water and Environment, observes Dhaka's water supply is heavily reliant on deep tube-wells and treated water, but the latter meets only about 20% of the city's water needs. "The Sayedabad treatment plant has a limited network, so approximately 80-85% of Dhaka's water comes from deep tube-wells. There are almost twice as many private deep wells compared to those operated by WASA," he said.

However, since the treatment plans are not enough to meet the demand, the current situation necessitates a continued reliance on deep tube-wells.

How to tackle this all-tangled crisis? 

The solution is straightforward. We have to harness surface water by any means possible.

Since Dhaka is fenced with six rivers around it, the rivers should be our first target. If we could treat water from Dhaka's western rivers: Buriganga, Turag and Dholesshori, it would possibly be manageable. 

Rivers should have been a blessing for Dhaka and Dhaka did not ever have to worry about Water, only if we did not kill the rivers around the capital.

Unrefined industry waste made Dhaka's water beyond refinable. "With long-term plans, we can revive the rivers," suggested Ainun Nishat, a water resource and climate change specialist, drawing an example of the Thames River in England. 

But that's in the unforeseen future. What now? There are a few water treatment plants (projects) ongoing. However, WASA fails to complete the projects in time.

"By 2029, Dhaka WASA will supply water among the city dwellers [with] 67% from surface water and the rest 33% from underground water extraction. Therefore, the underground water level will not have any bad impact from Dhaka WASA," said Mostafa Tarek, Deputy Chief Public Information Officer, Dhaka WASA.

The Prime Minister opened the Dasherkandi sewage water treatment plant in Dhaka last year, but questions were raised about a serious flaw – the $320 million, China-backed project was built without being connected to any local sewer network. 

Many of Dhaka's residents do not have access to sewage systems. Dumping of untreated sewage in local waterways is rampant. While inaugurating the plant, PM Hasina said it would allow the Dhaka WASA to treat "black water" from toilets in this, one of the world's most populated cities. 

The project would enable the DWASA to treat 500 million litres of sewage water produced daily in upscale neighbourhoods such as Gulshan, Banani, Baridhara, Niketan, Bashundhara and adjacent areas before being returned to the Balu River, commented Taqseem A Khan, the agency's managing director, at the opening ceremony last year.

However, officials with Rajdhani Unnayan Kartripakkha (RAJUK) and urban planners questioned the plant's usefulness without being plugged into a necessary pipeline network upon construction.

The plant came with its own cart-before-the-horse problem. 

Septic tanks in people's homes have capacity limitations. The homeowners secretly build underground outlet pipes which dump the sewage water to the drains, Gulshan Lake and canals which ultimately meet the rivers.

You cannot really blame them. What are they to do when there is no pipeline to carry the sewage water? You cannot expect them to take the sludge water by truck to the treatment plant.

Experts propose establishing new treatment plants not only for providing potable water but also for comprehensive sewage treatment; increase the capacity of existing facilities like Pagla, which involves multiple stages of treatment including stabilisation ponds and coagulation processes.

Also, there is a need to treat both domestic and industrial sewage before it enters water bodies like Hatirjheel and then rivers.

Inamul Haque suggests that we can consider implementing the activated sludge method for sewage treatment in small, localised plants due to limited urban space. "Utilise small spaces near parks and city corporation properties for setting up these sewage treatment plants," he said.

Photo: Mehedi Hasan

Another approach could be to develop sewage treatment plants specific to different regions of the city to manage waste more effectively and reduce the burden on any single system.

Dhaka is also a victim of greed, as the rivers are polluted by industry owners. We sell our future to productivity. It is time we enforced stricter control over industrial waste to prevent it from contaminating rivers. 

We also need to encourage industries to treat waste on-site using stabilisation ponds and septic tanks before releasing it into the environment. "This could be done under warehouse floors where space is limited," suggests Inamul.

While current reliance on deep tube-wells is necessary, future planning should focus on making surface water sources usable through better management and treatment practices. Finally, it's essential to conserve and protect existing water reservoirs. 

Considering the potential salinisation of the Buriganga River in the next 30 years, preparations should begin now to address this issue and ensure sustainable water sources for the future.

Ainun Nishat believes that "while the Buriganga, Shitalakha and Dhaleshwari rivers of Dhaka's south have substantial water, their contamination levels make them unusable." 

Plans to bring water from the Padma River are underway, but concerns remain about the sustainability of this source as the river's course changes naturally. Additionally, there are considerations to source water from the Meghna River, which is also an arduous task.

"Two decades ago, I emphasised the need to prioritise drinking water for humans alongside agricultural needs. The authorities did not pay any heed. Now I predict that in 30 years, the Buriganga River's water will become saline, and we must prepare for that eventuality," said Ainun Nishat.

To address these challenges, "we should maximise our water reservoirs. For instance, the swamp area between Ashulia and Birulia could be excavated to create a water reserve and recreational area, benefiting both water storage and community enjoyment," suggested Nishat.