National Geographic Society is kicking off the second phase of our landmark “Sea to Source: Ganges” expedition. Over the next few weeks, you’ll hear from our teams covering plastic pollution research from the perspective of water, land, and communities. Today, we go behind the scenes with the water team who are studying plastics in the environment and the flow of plastics through waterways and into the ocean.
Just over a week ago, the National Geographic Society’s “Sea to Source: Ganges” team arrived in Bangladesh ready for the second phase of our plastic pollution expedition. This time, we’re studying whether and how the flow of plastic into the ocean changes based on conditions that follow the region’s monsoon season. Our international team arrived from different areas of Bangladesh, India, the United States and the United Kingdom. We all reunited on our houseboat, named M.V. Dinghy, ready to work on the water for the duration of our time in Bangladesh.
Our houseboat is both our accommodation and science headquarters, and transports us along the Ganges, from where the river meets the ocean in the Bay of Bengal, all the way up near the border with India. Our first site, Bhola, is so far downstream where the river is so wide that you cannot see the other side. Bhola is a rural town that is currently buzzing with activity — when we arrived everyone was getting ready for the start of the fishing season.
On our first day in Bhola, we got ready to record scientific data and collect samples to understand more about plastic pollution in a major river system. When we head out sampling, we use a variety of boats. These range from small motorboats to large wooden fishing boats helmed by local fishermen.
We have a jam-packed science program, which includes:
- Taking water and sediment samples to understand the movement and accumulation of microplastic (plastic <5 mm) in a major river system. We will be able to compare the data from the pre-monsoon expedition, which took place in May, to understand seasonal variations.
- Collecting large plastic samples that have settled on the riverbed to understand if and how plastic is sinking. This involves sifting through lots of mud!
- Using cutting-edge drone imagery, we collect data about the amount of plastic on riverbanks and surface water.
- Recording the amount of fishing related debris at fish landing sites on the riverbank, which could potentially enter the river.
- Deploying bottle tags linked to satellites which will track where and how fast litter floats down the river.
In our first week of the expedition, it has been fantastic to reconnect with the communities we saw during the pre-monsoon trip and have them get involved with all of our sampling again. We have also been incredibly lucky to already see a lot of wildlife on our journey. We were the most excited, however, to see rare Ganges river dolphins at our second site, Chandpur.
We are now sailing to our next and final location in Bangladesh, before entering India.