Bangladesh grapples with surging chronic disease as climate change worsens water salinity due to rising sea levels. Local and international organisations are working to find impactful solutions.
Rising sea levels, frequent and devastating tropical cyclones, and storm surges have led to the inundation and contamination of freshwater supplies in Bangladesh.
Photo: Ishtiaque Hossain (Ratargul Swamp Forest, Bangladesh)
It is hailed as the ‘Land of Rivers’ and the atmospheric tourist promotional videos show mighty waterways weaving through the lush countryside, where locals and tourists revel in the natural resources of ‘Beautiful Bangladesh’.
The waters which power down from the Himalayas and mature into an expansive delta featuring the Sundarbans, the largest mangrove forest on the planet, are magical, mystical, and a major attraction for travellers.
But, away from this picture postcard view is the grim reality of rapidly dwindling and deteriorating water sources for domestic and agricultural use, with climate change exerting a chokehold on the nation’s future.
Sale of desalinated water is now a growth business with a desperate rural population compelled to spend some of its meagre earnings on a natural resource.
Rising sea levels, frequent and devastating tropical cyclones, and storm surges have led to the inundation and contamination of freshwater supplies—held in low-level ponds or underground aquifers—with saltwater.
This has alarming consequences for the 35 million people living in Bangladesh’s coastal regions. The harmful effects of drinking water with high sodium content include increased blood pressure, progressive kidney disease, and gestational hypertension in pregnant women.
The 19 districts of the low-level region, across 47,201 square km, have little protection against the encroaching seawater. A government report in 2010 stated that water salinity had increased by 26% over the past 35 years, and recent climate change impacts are compounding the contamination.
The heightened salinity not only makes the water dangerous to drink but also impacts farming by both reducing the yield and stunting the nutrient content of crops.
There are grim projections that more than 13 million people in Bangladesh may become internal climate migrants by 2050 as agricultural GDP falls by one third.
Symptomatic of this looming catastrophe is the fact that, in the ‘Land of Rivers’, sale of desalinated water is now a growth business with a desperate rural population compelled to spend some of its meagre earnings on a natural resource.
Funding initiatives to redress water salinity
The battle to turn the tide of climate change is being fought on many fronts. Local and international organisations are focusing their energies on novel methods of water purification, rainwater harvesting, irrigation and crop management that save water, and development of rice strains that are saline-resistant and need less water to cultivate.
"We have one of the lowest greenhouse gas and carbon emission rates in the world yet we are on the frontline, facing the worst of climate change."
But experts fear these measures will merely slow the erosion of public health standards and the delta itself unless the international community follows through on its pledge under the UN Climate Change Conference COP27 to provide financial assistance through a Loss and Damage Fund to the most vulnerable nations impacted by climate change.
Mohon Kumar Mondal, who founded and runs the non-governmental organisation LEDARS (Local Environment and Agricultural Research Society) in Satkhira, southwest Bangladesh, frames the issue neatly, saying: “We have one of the lowest greenhouse gas and carbon emission rates in the world yet we are on the frontline, facing the worst of climate change. We are the ultimate sufferers because of our geographical location.”
He says the international community is obliged to help. “At COP27, they agreed to compensate for loss or damage caused by climate change. Every year, Bangladesh faces disasters that are causing huge loss and damage. We have some good community projects operating here but they need more financial support, and I’m not sure when that Loss and Damage Fund money will come. In the meantime, people are suffering. Local people are migrating from the coast and living in slums in cities and having miserable lives.
“It is very sad that people cannot make a way of life where they were born and, if we don’t respond quickly, the area will become barren, and people will have no choice but to leave. How can they survive here?”
LEDARS is involved in a range of initiatives to redress water salinity and won the prestigious Zayed Sustainability Prize in 2013 for its work in installing 5,250 biosand filters, 33 pond-sand filters, 185 rainwater harvesting systems, and 21 protective ponds to create access to safe drinking water for more than 15,000 people. It also excavated three canals and installed seven deep-tube wells and 68 mini ponds to support cultivation of rice and vegetables through the year on lands that were previously barren.
The projects, which LEDARS hopes to scale up with the award money and grants from the UAE, help communities supply their own safe drinking water and develop self-sufficient farming.
“We are a small NGO, but we have lots of initiatives to increase agricultural resilience, such as growing vegetables with minimum water,” Mondal says.
Outlining the growing scale of health problems at a community level due to rising levels of water salinity, he says, “Hypertension is increasing among men and women, with pregnant women facing a higher risk of miscarriage. The women working with saline water suffer from cervical infections and some young women need surgery.”
Pursuing a mosaic of solutions
When yields fell in Bangladesh’s arable land due to ground salinity, many families gave up paddy cultivation and took advantage of the salty ponds to farm shrimp. It generated income but also worsened the salinity levels.
"We need global mitigation solutions to halt and reverse climate change, but that might take years. Until then, we have to develop these solutions because the problems are here and now. We have to focus on what we can do to improve health outcomes for these populations today."
To encourage a return to rice cultivation, the Bangladesh Rice Research Institute developed a new strain that can grow in water with triple the normal level of salinity. This could increase crop yields by 11.75% by 2050.
The mosaic of solutions includes ground-level schemes such as communities strengthening and raising embankments to protect against the increasingly frequent storm surges, and growing crops on ‘floating fields’—artificial islands that rise and fall with swelling waters—to steer clear of the salty water below.
At the other end of the spectrum, a £10-million (US$12.46-million) grant established the NIHR Global Health Research Centre on Non-Communicable Diseases and Environmental Change with a remit to focus on challenges in Bangladesh, India and Indonesia. The centre, a partnership led by Imperial College, London, and The George Institute for Global Health, India, will research methods of tackling the rising burden of non-communicable diseases (NCDs) in low- and middle-income countries (LMICs) impacted by environmental change.
“We're trying to work with the local populations to develop solutions that will allow them to clear the water of excess salinity. We are keen these are locally developed and can be implemented within the limits of the resources available in those regions and not imposed from outside,” says Professor Vivekanand Jha, co-lead of the centre and executive director of The George Institute for Global Health, India.
He says the centre’s team engaged extensively with local communities to not only understand the scale of their challenges but also be guided on solutions that are achievable and sustainable.
“When we go into the community, we work with them—not around them. We want co-creations because Indigenous knowledge is so important. We ignore Indigenous knowledge and information at our own peril,” Jha says.
“We include members of local communities on our research team and value their input as it is good for them and the projects,” he says, adding that the projects, if shown to be successful, are more likely to be implemented to scale when there is local involvement.
The five-year project, which started in October 2022, is expected to generate evidence that will underpin major strategies to arrest the impact of climate change and NCDs in Bangladesh—but, crucially, its success depends on broader global efforts to combat climate change.
“We are currently focusing on adaptation solutions: the climate is changing so how do we adapt to it?” Jha says. “These [solutions] will not, of course, succeed on their own. We need global mitigation solutions to halt and reverse climate change, but that might take years. Until then, we have to develop these solutions because the problems are here and now. We have to focus on what we can do to improve health outcomes for these populations today.”
Rising water salinity will impact future generations
Implementing these solutions will be a race against time as sea levels in the Bay of Bengal are rising by 3mm a year, and in low-lying Bangladesh saltwater will continue to ingress and contaminate freshwater.
"Not only is there a direct impact on the current population, but there is also an indirect impact on future generations."
The health impact is particularly severe in pregnant women, Jha explains. “Drinking water high in salt content increases the risk of NCDs, and high blood pressure is extra dangerous in pregnant women because it can lead to premature birth, and even neonatal and intra-uterine deaths.
“Babies may be born with small birth weight [and] are at risk of developing NCDs such as hypertension, diabetes, and kidney disease. So not only is there a direct impact on the current population, but there is also an indirect impact on future generations.”
Epidemiologist Professor Paolo Vineis has been charting the health and social issues caused by high water salinity in Bangladesh for 15 years, after one of his PhD students spotted an epidemic of pre-eclampsia in women living in a coastal region and traced it to the high sodium content in their drinking water.
“The effects of climate change are multiple and some of them might be more serious than exposure to salty water—such as loss of agricultural productivity and, therefore, a lack of quality food,” says Vineis, who is chair in environmental epidemiology at the MRC Centre for Environment and Health and Imperial College, London.
“The intrusion of salty water into soil results in impoverishment of crops, so what [people] do manage to grow has lower levels of essential nutrients.”
High water salinity in Bangladesh leads to health and social issues stemming from loss of agricultural productivity and lack of quality food.
Photo: Aneire Khan
Promoting local endeavour and ingenuity
Vineis’ team, which is part of the NIHR Global Health Research Centre project, is exploring ways to improve agricultural performance and preserve water, but a prototype solar power water purification system that removed salinity through evaporation proved difficult to scale. Logistics is challenging in a vast area ribboned with waterways, and where roads are prone to subsidence or risk being washed away.
“The country lacks infrastructure; and building anything in remote areas is very difficult. It is hard to say how scalable our solutions may be,” Vineis says. “Certainly, Bangladesh needs more technical support and international help.”
The depth of financial assistance from the Loss and Damage Fund is yet to be fixed so Bangladesh must continue to explore novel methods of protecting its people. It has had plenty of practice and is acknowledged as a leader in climate adaptation and disaster preparedness.
The country increased water and sanitation funding by 30% from 2019 and its burgeoning microfinance industry has partnered with Water.org, a global non-profit organisation co-founded by Hollywood actor Matt Damon, to provide small affordable loans to improve access to water, sanitation, and hygiene.
Tackling climate change is part of the nation’s DNA, with even students encouraged to devise climate-smart growth projects, and local communities rebuilding embankments and sea defences. For Mondal, who has two children, it is something more: “I was born here and got an education from the government, so it is my duty to put back because my neighbours and relatives are suffering,” he says. “I have to do this. I have travelled and had the opportunity to settle abroad but I couldn’t because I have a dream of helping my people.”
The sentiment and endeavour at ground and sea level in Bangladesh is powerful, but it is clear that the global community has to make good its promise to provide transformative aid. And it needs to be quick.