Life on the river: helping make Bangladesh more resilient to climate change

There are places in Bangladesh that flood for up to eight months a year.

In recent years, the effects of this flooding have gotten significantly worse.

In June 2022, extreme flooding hit Sylhet, a city in the north-east of Bangladesh, where over 1500mm of rain fell in less than a month affecting over 7 million people and killing over 140 people.

This compares to the UK average rainfall in 2022 of 1051 mm.

For centuries, villages here have just about managed. Until now.

Since the start of the year, I’ve been working with a team on a project that could hold the key to helping millions on floodplains all over the world to survive, adapt and overcome.

Bracing for the monsoon

Rivers in Bangladesh are subject to continuous and significant change.

Each year between June and October, the monsoon season hits, adding to the flows originating from Himalayan snowmelt and surface runoff.

This results in the overflowing of rivers and flooding of surrounding land. Recently, rainfall has become more irregular and extreme due to the effects of climate change.

This not only results in the displacement of millions of people, but also damages crops and impacts animal populations.

To add to this, the highly erodible soils which form much of Bangladesh, predominantly made up of sediment deposits, result in millions losing their homes.

These people are often called ‘erosion victims’.

Lack of flood defences

Bangladesh is blessed by natural resources and fertile land, but people struggle because of the extreme climate.

For generations, many families have had to spend everything they own on protecting their homes from flooding.

This has typically been in the form of creating inadequate flood defences which constantly fail.

These rudimentary structures would result in a constant fight to protect the land.

As a result, farmers only have a few days to harvest their crops when the rainy season comes.

Impacts of erosion and flooding

Many have had to come to terms with the huge economic losses associated with flooding, struggling to keep crops and livestock alive.

Flooding, hails storms, drought and flash flooding have become increasingly common in the area, forcing people to migrate.

Many move away from the river towards the capital, Dhaka, making it one of the most populated, congested an polluted capitals in the world.

From the early 1970s to the early 2000s, the average width of the braided river system in Bangladesh increased by 50%.

The Jamuna River corridor alone widened from around 8km to 12km. Over 80,000Ha of land has been lost due to erosion of the riverbanks.

Around half of this land has been replaced by river channels and infertile sand bars and the other half by semi-permanent chars (vegetated islands) of lesser agricultural value.

When visiting these sites, you come to terms with all your privileges.

Here, there are no social protection measures or insurance schemes, it’s life or death.

Taking action through civil engineering

The Flood and Riverbank Erosion Risk Management Investment Programme (FRERMIP) aims to reduce flood and riverbank erosion risks along the Jamuna and Padma rivers.

This is done through structural and non-structural interventions, and institutional and knowledge-based capacity building.

The project aims to narrow the channel into a stable corridor and incorporate the UN Sustainable Development Goals, ensuring that all interventions balance social, economic and environmental sustainability.

Flood embankments, sluice gates and riverbank protection are being built using sand filled geotextile bags.

To arrive at a flexible planning and construction process, a new methodology has been developed, termed the ‘adaptive approach’ to riverbank protection.

This use of phased construction provides the option of emergency works consisting of dumping a larger amount of geotextile bags alongside the eroding riverbank.

This protection will self-launch and protect the slope during the next flood season before the main works start, ensuring the long-term sustainability and function of the river training works.

Importance of social outcomes and education

I recently visited a high school in the small town of Bachamara, along the left bank of the Jamuna River.

A large flood embankment is planned here.

Mr. Rahman, a teacher at a school, told me how hard it was for children to get to school in the wet season:

“Children often come to school by boat. This is usually in very bad weather and unsafe for the children resulting in many incidents along the way. The school is the only source of opportunity for many of our students so we have to do all we can to provide protection”.

I learned that the school not only acted as a centre for education, but also as a refuge centre for the community in times of flood.

It was also responsible for educating over 300 girls, who would otherwise have little opportunity to learn in the area.

It was therefore crucial that the embankment was constructed as soon as possible.

The money previously invested by locals on temporary flood defences can now be spent on education, health and integrating the community.

Bangladesh is showing that climate change is real, but adaptation is possible if the right support is available.

Reflecting on working in international development

Many of us take a lot for granted when living in developed countries.

We have access to food and healthcare, and a right to funded education.

Working here has made me appreciate something else too: the power of civil engineering.

By sharing our knowledge on a global scale, we can ensure that infrastructure can be delivered in a sustainable and resilient way.

We can offer hope for those who need it the most, while providing them with the skills to become self-dependent and manage these risks in the future.

The work being supported by international funding agencies on project such as FRERMIP are proving that civil engineers can make a real difference.

Even though millions here live under the constant threat of a changing climate, practical engineering solutions are giving the next generation hope.

If you’re interested in working in international development or overseas, why not see how you can get involved by asking your manager or searching on the ICE website.