Drinking wells in the villages of southwest Bangladesh have been contaminated with salty ocean water for so long, people have gotten used to the taste. Now, scientists think that worsening salinity could be having dire, long-lasting health effects on the people living in the region — and climate change is likely to blame.
The world’s nations are meeting in Paris to address climate change and work towards an agreement that would limit global warming to two degrees celsius. But even if an ambitious, legally binding agreement is made, many coastal communities worldwide, including those in India and in American states like Florida, will face freshwater shortages in the coming decades as oceans continue to rise and further contaminate drinking water.
As a low-lying country in which nearly a third of the population lives below the poverty line, Bangladesh is particularly vulnerable. Already, scientists and researchers are referring to Bangladesh as the “ground zero” of climate change, foreshadowing the water shortages that will likely spread around the world and affect more than one billion people by 2060, according to the United States Geological Survey.
“Bangladesh stands at the forefront of saltwater contamination,” said Aneire Khan, a consultant for the International Centre for Diarrhoeal Research, Bangladesh. She was the first to broach the topic four years ago in a study conducted in Dacope, a small administrative district in coastal southwest Bangladesh. “However, the same trend potentially affects all 11 Asian large river deltas, and other major deltas, notably the Nile and the Mississippi,” she said.
When Khan visited Dacope’s local hospital, she discovered alarming rates of high blood pressure-related conditions among pregnant women which she linked to high salt content in local drinking water sources.
Khan and her team measured blood pressure and took urine samples from women in the community and found that the number of hypertension cases was almost eight times higher than in non-coastal regions of Bangladesh.
High blood pressure is among the lead causes of maternal death in developing countries, according to the World Health Organisation. Heavy salt intake increases the risk for coronary heart disease, which is the single most important risk factor for stroke, Khan explained. High blood pressure also makes pregnant women particularly vulnerable to a condition called pre-eclampsia, which can lead to severe headaches, organ damage, and even death.
Khan’s study caught the attention of Susmita Dasgupta, lead environmental economist for the Development Research Group at the World Bank.
With a team of researchers, Dasgupta began to investigate how saltwater consumption during pregnancy affects infants. She found that babies whose mothers consumed saltwater during the last month of pregnancy were at risk. Indeed, their survival rates were as badly affected as by other factors known to determine infant mortality, such as a mother’s age, education and availability of toilet facilities.
Dasgupta also noted that climate change is likely to exacerbate existing salinity problems.
The rising seas and increased storm surge in coastal Bangladesh breach groundwater wells and rivers, turning these water sources salty. Even though freshwater is abundant during the monsoons, resulting in major floods, it’s the opposite during winter. As the ground dries up and rainfall peters out, salt stays behind. During this dry season, the level of salt concentration in drinking water can reach as high as eight times what is deemed safe by the World Health Organisation, according to research from Imperial College in London. This is worsened by shrimp water farming in these regions.
The issue is not new – communities in southwest Bangladesh have battled the rise of the ocean and violent typhoons for decades. But with each passing year, the problem worsens at an unprecedented rate. The typhoons that accompany climate change have gotten stronger, and Khan found that drinking water sources as far as 100 kilometres inland Bangladesh are turning into brine. Research shows that in the last 35 years, salinity in the country has increased by 26 percent, putting the 40 million people who live in coastal Bangladesh in danger.
Bangladesh is rapidly disappearing under the sea, and its people are increasingly forced to adapt or to simply move to parts less vulnerable to flooding and salinity.
Numerous NGOs and international organisations, like BRAC, Shushilan, the World Bank, and Concern International are trying to solve the issue and prevent a mass exodus of people from the coastal parts of the country.
There are three main ways that NGOs and the Bangladeshi government are trying to improve freshwater access in these areas, said Santanu Lahiri, a water supply and sanitation expert for the World Bank. The most traditional of these approaches involve building standing freshwater ponds, where rainwater is collected and stored for the dry season. However, this is hardly fool proof — as these ponds can remain unsheltered from the elements, the water sometimes evaporates and can be contaminated by outside sources, said Yan Zheng, a scientist at the Lamont-Doherty Earth Observatory at Columbia University.
Instead, some scientists are adopting a second method, explained Jonathan Gilligan, a professor of environmental science at Vanderbilt University who has conducted extensive fieldwork on flooding in southwest Bangladesh. They are setting up aquifer recharge stations, where freshwater is pumped deep into the ground. Once there, it can be stored without risk of contamination for up to two years, said Gilligan.
A third method is that of reverse osmosis, added Lahiri, which removes salt from the water to make it potable. But this is an expensive and time-consuming proposition, requiring financing, proper management and regular maintenance — all things that these small communities often are unequipped with, according to Zheng.
In a country plagued by political instability and poverty, it may take years for solutions to spread across the region. While major NGOs and even governments like the European Union are investing into projects and research, many of these projects are still at an experimental stage. Implementation continues to prove a challenge, with limited funding, fragmented resources and difficulty in accessing the areas that are worst affected.
“We can’t deliver sustainable development without taking urgent action to tackle climate change and supporting the communities already suffering from its impacts,” said Saleemul Huq, director of the International Centre for Climate Change Development in Bangladesh and a regular attendee at the international United Nations climate change meetings. “In Paris, governments can start delivering on their newly enshrined development goals.”