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Message on a Bottle: How One Expedition Is Engaging Communities to Learn About Plastic Waste

The “Sea to Source: Ganges” expedition team is deploying wooden drift cards that mimic the flow of plastic waste from source to sea and engaging local communities to help track them.

The “Sea to Source: Ganges” expedition team engages communities to help them track plastic pollution with wooden drift cards.

An international, all-female team of scientists and engineers are currently on an expedition to study plastic pollution in the Ganges River. The main goal of the “Sea to Source: Ganges” expedition is to better understand and document how plastic waste travels through waterways and identify inclusive solutions to the plastic waste crisis. The “Sea to Source: Ganges” expedition is the first of several international river expeditions planned as part of National Geographic’s Planet or Plastic? initiative, which aims to significantly reduce the amount of single-use plastic that reaches the ocean.

Throughout the expedition, the team is deploying drift cards made of eco-plywood that are shaped like a plastic bottle and will help mimic the flow of plastic waste through the Ganges watershed. The drift cards are engraved with instructions for people who see them to contact a number via WhatsApp or SMS with the card’s location and its identification number, engaging the local communities in the expedition's efforts. The drift cards are made by a company called Cut by Beam, which is run by Jenny Shipley, a young creative product designer in the UK out of a rural workshop that is almost entirely solar powered and has a strong environmental ethos.

Two of the expedition team members are Emily Duncan, a National Geographic Explorer and post-doctoral researcher at the University of Exeter, and Amy Brooks, a doctoral student in engineering at the University of Georgia New Materials Institute. We caught up with Emily, Amy, and Jenny about the expedition and how they plan to use these drift cards to study plastic waste.

Photo by Kathryn Youngblood

NGS: What’s the goal of using these drift cards?

AB: Using drift cards will allow us to trace the movement of plastic waste on land and in waterways. For the land-based team, there is currently a knowledge gap of exactly how much plastic waste is reaching the aquatic environment from land. We know that there is waste on land that is being washed, blown, or otherwise transported into the sea, and rivers can be a direct pathway for this. It’s been estimated that eight million metric tons of land-based plastic waste reaches the ocean annually and 1.8 million metric tons of this may be from rivers. We’re going to experiment using the drift cards to research how much waste makes it from the land into the water.

In each of the communities we’re working in, we’re going to be collecting data on observed litter on the ground using a Marine Debris Tracker, and we are depositing the drift cards in these same areas where we see litter.

ED: Over time, with help from community members and citizen scientists finding and reporting the cards, we will then know where each card ends up, which will help us understand if and how the pieces of litter that we tracked on land might be transported to the Ganges, and ultimately the Bay of Bengal and beyond. This is a way to help validate what we know about land-based plastic waste reaching rivers and then the ocean, and if successful, there is an opportunity to expand this research to other watersheds around the world.

NGS: Have drift cards like these ever been used to study plastic pollution?

AB: Yes, drift cards have been used to study plastic pollution. A project based in Germany is using drift cards to study plastic waste in the North Sea. In the United States, a team of researchers also used wooden drift cards to study plastic pollution in Hawaii.

NGS: What are the drift cards made of?

JS: The drift cards are made of eco-plywood that has been sourced from sustainable resources, certified by the Forest Stewardship Council.

NGS: Will the drift cards pollute the environment?

JS: No. The drift cards are made of eco-plywood that has been laser cut. The benefit of laser cutting is that we are able to mark the wood without adding any paints or pigments to the material, so the drift cards will not pollute the environment.

NGS: How are they made?

JS: The drift cards are laser cut to create the bottle shape and engraved to add the instructions. We have designed the shape and size of the drift cards to make maximum use of the eco-plywood and keep offcuts to a minimum. Any offcuts that we do get can be used in the biomass boiler on-site that is used to help heat the workshop.

NGS: How big are they?

JS: Each drift card is 15 cm x 6 cm—about the size of a small plastic water bottle that has been flattened.

NGS: How many drift cards will you deploy?

AB: We’ll deploy 100 on land, 100 in the river, and 100 on the riverbank at each of the sites visited during the “Sea to Source: Ganges” expedition.

NGS: How will you decide where to deploy the drift cards?

AB: We’ll be depositing the land-based drift cards in the same areas in which we record litter on the expedition. We will also conduct riverbank and coastal cleanups in each community, and during these, we’ll involve community members to help release them.

NGS: What should someone do if they see one of the drift cards?

AB: Please report them! You can message +880 1-970101347 using SMS or WhatsApp with the drift card location and the individual identification number written on the card. A picture would be very helpful too, but is not required.

NGS: What will you do with the data you collect from the drift cards?

AB: We'll use the data to evaluate the transport of plastic to the river by using geospatial analysis and mapping tools. We also hope that this will engage the community more directly in our science.

NGS: What do the drift cards say?

AB: The drift card message is written in Hindi on one side and Bengali on the other. In English, it translates to “For Ganga. For science. Help the Ganga Guardians understand how trash flows down the river. Message +880 1-970101347 using SMS or WhatsApp with this card’s location. Include card number and photo, if possible. Then put it back where you found it. Thank you.”

The expedition team plans to share their expedition experiences in real time. Follow along on social media with #ExpeditionPlastic or through the team’s digital field journal:

Hear more from the “Sea to Source: Ganges” expedition team at the 2019 National Geographic Explorers Festival June 11-13. Learn more about the ways National Geographic is working to tackle the plastic waste crisis here.

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