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“Sea to Source: Ganges” Dispatch: Bottle Tracking – How Plastic Moves through the Ganges

Land, water, people, plastic. This is the story of National Geographic Society's female-led expedition team as they track & characterize plastics in the Ganges River using land-debris trackers, community surveys & water-air-sediment sampling. Written by Lillygol Sedaghat and edited by Cory Howell.

“Is it possible to do something crazy like track a bottle down a river?” 

Heather stood with her arms over Al’s cubicle partition while he looked up at her. They were in the Zoological Society of London (ZSL) office.

“I’d need it in six months’ time,” she went on. “Can we do it?” 

The two were longtime friends, avid conservationists who had spent their entire lives working to protect marine wildlife and preserve the oceans. 

Alasdair, or Al for short, knew that Heather never asked a question without having a plan of action in mind. “Yes,” he said without skipping a beat. “Count me in.”  

 Lillygol Sedaghat
The inside of the bottle tag. Photo courtesy of Lillygol Sedaghat.

Conservationists have used GPS to monitor turtles and other marine wildlife since the 1990s. Heather’s idea was based on a simple premise: Why not use the same technology on plastic?

To bring the idea to life, Al teamed up with Craig from Icoteq, an electronics engineer by trade and conservationist at heart. Together, they built a plastic “water bottle” prototype filled with GPS tracking and wireless communications technology. 

Using cellular and satellite tracking, they created the first open-source plastics tracking platform, which shares real time data and even the bottle design. 

The device sends ‘pings’ every hour, using a cellular connection for urban environments where there is coverage, and a satellite connection when or if it makes it into the open ocean. 

The bottle design was straightforward: they wanted to model how something like a plastic bottle moved through the river system. But it was also a pragmatic decision–the design needed to float, otherwise it couldn’t broadcast its cellular location. 

Lilly about to throw “Lilly,” the bottle tag, into the river.
Lilly about to throw “Lilly,” the bottle tag, into the river. Photo courtesy of Lillygol Sedaghat.

Al was adamant about using open-source conservation technology in his design; he wanted anyone to have access to his data and methods.

“The barriers today [for researchers] are not due to price or obstacles,” he said, “but lack of access to cutting edge data and technology.”

And at most large organizations, researchers get stuck in the cycle of writing grants to afford access. He wants to break that cycle.

“We want this data to be inclusive and usable for all communities,” he shared, “that’s why bottle GPS is open…you can make your own sensor or enhance functionality [of your own model] without re-engineering the core.”

They brought ten plastic bottle-shaped tracking devices to India with three main questions:

  • How long does it take for plastic waste to get from source to sea?
  • How much plastic gets to the ocean?
  • How much gets stuck in the river system?

“We want to know what [plastic] is doing, where it is,” he said. “[This] will tell a story.” 

And with that story will be the data they can use to inform solutions and policy. 

“Is this a localized problem we need to tackle per section [of the river] or does a solution need to be applied across the Ganga?” Craig said. 

Craig and Imogen on the Ganga tracking the flow rate of the river before releasing a bottle tag.
Craig and Imogen on the Ganga tracking the flow rate of the river before releasing a bottle tag. Photo courtesy of Lillygol Sedaghat.

But then, there’s the ethics issue. 

The idea of releasing plastic into the river to track its flow can be controversial. 

Ultimately, they made their decision. The ten plastic bottle tags were released in different locations and sections of the river. 

Since then, some devices have been very active, pinging regularly to update us on their respective locations. Other devices have gone completely silent. And still others have been taken out of the river, moving robustly through village communities. 

Each bottle is an experiment, and each dataset will tell a story. Where it goes or doesn’t go, how quickly it flows or doesn’t flow; where it gets stuck, where it gets picked up. This is a journey of ten tags at the whim and will, beck and call of the river, led and shaped by Mother Ganga and her powerful forces. 

Post written by Lillygol Sedaghat and edited by Cory Howell.

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