In Bangladesh Coastal region, Cry for Clean Water in the dry season
Since the beginning of April month, there has been a cry for clean water. This cry is from the people of the southern coast of Bangladesh. Salinity has increased drastically in almost all water sources. During the dry season, the salt water of the Bay of Bengal makes the coastal rivers salty.
Climate change has led to rising salinity in water sources during the dry season over the past 25-30 years, resulting in a serious clean water crisis. Those who store rainwater during the rainy season are somewhat relieved. And those who do not have that means are forced to use brackish water for drinking and other purposes.
The coastal region of Bangladesh is particularly unique compared to other areas of the country. The 2022 Population and Housing Census shows that around 43.8 million people reside in the 19 districts of Bangladesh’s coastal region.
The concern is that this region, known as a crisis and potential area, is particularly vulnerable to climate change.
After Cyclone Sidr in 2007 and Cyclone Aila in 2009, almost all freshwater sources have been damaged by saltwater intrusion. Rising salinity in agricultural land and freshwater is causing a serious shortage of drinking water and affecting crop production.
The Bangladesh National Data Portal reports that saline land on the coast has increased by about 27 percent in the last 40 years. The salinity of groundwater has also spread 50 to 70 kilometers upstream from the coast, depending on the level.
As a result, groundwater sources are being severely damaged. Rising sea levels from climate change are increasing salinity intrusion and depleting freshwater reserves underground.
A US research report says that in coastal areas, saltwater and groundwater maintain a balance. Freshwater accumulates in water bodies through rainfall.
However, due to the tides of the sea, saltwater tries to enter the land. As a result, an equilibrium is created. Rising sea levels are contaminating most drinking water sources with brackish water.
Bagerhat, Satkhira, and Khulna districts face a serious crisis of clean and safe water. In coastal areas with saline water, safe water sources include freshwater ponds, rainwater harvesting, deep tube wells, piped supplies, pond sand filters (PSF), and reverse osmosis (RO) plants.
Deep tube wells are most commonly used for extracting safe groundwater. In many coastal areas, groundwater levels have dropped, causing tube wells to either not yield water or to draw up brackish water.
Apart from this, groundwater is lifted through pipelines in urban areas or surface water is lifted and purified and supplied. This water is not always safe.
The poor people of the villages use freshwater ponds for drinking water. In most cases, due to the distance to freshwater ponds, people have to travel miles to collect drinking water.
Pond sand filters (PSF) collect and filter rainwater from freshwater ponds using sand and gravel, making it safe for drinking.
This method is environmentally friendly and sustainable. Apart from this, saline water can be converted into drinking water through reverse osmosis or R.O.Plants. However, this method is relatively expensive and difficult to maintain.
Climate change will lead to more natural disasters like cyclones, floods, and droughts, impacting water sources. The level of salinity in coastal water will increase further.
Given the situation, rainwater conservation systems are the most effective adaptation method for the dry season.
