Frequently Asked Questions
Frequently Asked Questions
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Bubble Barrier Technology
How does the Bubble Barrier work?
We create a bubble curtain by pumping air through a perforated tube located at the bottom of the waterway. The bubble curtain creates an upward current that directs plastic waste to the surface.
By placing the Bubble Barrier diagonally across the river, the natural flow of the water helps push plastic debris to the side and into the catchment system. This catchment system is specifically designed to work in harmony with the bubble curtain to efficiently collect and retain plastics. Once collected, the plastics will be removed for processing and reuse.
Bubble curtains have been used for a long time and are commonly found in the oil and dredging industries, as well as in the Dutch lock system. The Bubble Barrier system, developed by The Great Bubble Barrier, is the first bubble curtain designed explicitly for capturing plastic pollution.
Which Bubble Barriers are currently in use?
There are several active Bubble Barriers capturing plastic pollution across the globe. You can find all Bubble Barrier projects on our Projects page.
How is the plastic pollution collected?
Once plastic pollution encounters the Bubble Barrier, it is guided to the side of the waterway, where it's collected in the catchment system.
The catchment system is tailored to work with the existing infrastructure of the specific location. Depending on the Bubble Barrier location, the catchment system will then be emptied from water or land for further processing.
Does the Bubble Barrier allow fish to pass?
Bubble Barriers are safe for fish migration. Most species will pass through the bubbles or take a short time before they pass it. We nevertheless implement an additional fish passage in each design under the catchment system. With every new project, the local ecological impact of a Bubble Barrier is carefully considered in collaboration with ecologists. Our latest research focused on smaller fish around the Bubble Barrier Amsterdam. This research showed smaller fish passing through the Bubble Barrier and underneath the catchment system. You can find more information on fish and their interaction with Bubble Barriers in our whitepaper.
Whales use bubble-net feeding to hunt fish. Does the Bubble Barrier have the same effect on fish?
Humpback whales use the so-called "bubble-net feeding" method to concentrate herring near the water surface. Whales use air bubbles to blow a ring around the school of fish before they jointly breach the surface and feed on the fish. Research suggests that the main driver behind the concentration of the fish is the sound that the whales make when they blow the bubble ring. The bubbles will create a “wall of sound” which scares the fish away from it rather than being afraid of the bubbles themselves. The Bubble Barrier technology is thin and silent, using tiny bubbles, which don't come as a surprise to passing fish.
Can the Bubble Barrier be used for something other than plastic capture?
Bubble curtains can also be used for other applications than the capture of plastic. However, the Bubble Barrier system focuses on the capture of plastic pollution in waterways.
For all other bubble curtain applications, we would like to put you in touch with one of our partners.
Effectiveness
How much plastic waste of which sizes can a Bubble Barrier catch?
Bubble Barriers have a catch rate of 86% of the floating plastic pollution in a waterway.
The technology effectively catches plastics from 1 mm to 1 m in size.
Find out more about the impact of specific Bubble Barrier projects on our Impact page.
Can the Bubble Barrier capture microplastics?
Bubble Barriers can capture microplastics as small as 1 millimetre in size. They often collect tiny particles of styrofoam as part of their average catch.
Bubble Barrier Wervershoof has been installed at a wastewater treatment plant as part of a research alliance to research its effectiveness in trapping microplastics smaller than 0.5 millimetres. Further research is needed to assess how well the Bubble Barrier performs with even smaller microplastics.
Which types of plastic are caught by the Bubble Barrier?
Bubble Barriers can catch all types of plastic materials. During our monitoring programs, we have identified plastic waste in over 100 categories, such as personal care products, food packaging, and fireworks. We often find a staggering amount of microplastics, especially styrofoam particles. The Bubble Barrier can also capture larger items, for example; we have retrieved multiple Christmas trees and television sets from our catchment system.
During lab testing of our technology at Deltares, various types of plastics were studied, including packaging, water bottles, popped balloons, plastic bags, bottle caps, and plastic grit. The Bubble Barrier effectively captured the majority of both floating and underwater plastics. However, plastic that has sunk and is rolling slowly along the bottom of a waterway is unlikely to be captured.
What type of rivers are suitable to be cleaned with a Bubble Barrier?
The Bubble Barrier operates effectively in most rivers. While there are some limitations due to the unique characteristics and regulations of different waterways, we have yet to fully identify the limits of our Bubble Barriers. This is why we are eager to take on more projects and push the boundaries of what we can achieve.
We are continually improving our Bubble Barrier system to address as many river locations as possible. Since small urban rivers are major contributors to plastic entering the ocean, we have prioritised tackling these rivers first. Contact us to find out if we can clean your river.
Material
What is a Bubble Barrier made of?
The Bubble Barrier creates a bubble curtain by pushing compressed air through a perforated tube placed on the bottom of the waterway.
The tube is made of durable EPDM and reinforced with an anchoring system upon implementation in the waterway.
Plastic Extraction & Use
What happens to the collected (plastic) waste?
Plastic caught by our Bubble Barriers is collected by the local Water Authority who in turn send it to a recycling centre. Wherever we implement a Bubble Barrier we help to ensure the waste is processed most sustainably through existing waste management systems.
For most Bubble Barrier projects, the plastic waste is sorted and monitored for a certain period to collect impact data. The types, sizes and sources of (plastic) waste are researched in these monitoring programmes. Valuable insights and data, resulting from the monitoring, can be used to strengthen the urgency to act and advocate for policy change to tackle plastic pollution in waterways. The Great Bubble Barrier and our partners use the OSPAR-river method when monitoring waste captured by Bubble Barriers. The OSPAR-river method is a riverbank litter monitoring protocol that offers a practical and standardised framework, sporting over 100 individual waste categories.
We are currently exploring with partners to recycle the collected plastics. However, as a tech scale-up, we focus on the efficacy and deployment of the Bubble Barrier technology and its catchment system. Other great innovative companies focus on sorting, identification, and recycling of river plastic only.
Energy Consumption
How much energy does a Bubble Barrier use?
The Bubble Barrier uses compressed air, pushed through a tube, to create the bubble curtain. The width of the waterway, and thus the length of the bubble curtain tube significantly influences the necessary energy usage. Wherever possible, we try to power our Bubble Barrier with renewable energy.
The first Bubble Barrier in Amsterdam runs on 100% green energy and has about the equivalent energy use of an electric street sweeper in The Netherlands. As each waterway and city has its specificity, the energy needed to power the Bubble Barrier system varies. Our commitment remains unwavering: a cleaner future powered by renewables is the only future we envision.
Strategy & Team
What is the mission of The Great Bubble Barrier?
The Great Bubble Barrier aims to remove as much plastic pollution as possible from waterways using Bubble Barriers.
Besides cleaning rivers from plastic, we:
- Monitor the amount of plastic in waterways to ignite policy change
- Increase awareness of plastic pollution
- Ensure sustainable processing of the catch
Are there career opportunities at The Great Bubble Barrier?
The Great Bubble Barrier is a young and fast-growing Dutch scale-up based in Amsterdam, the Netherlands. To get the rivers free from plastics, we’re always looking for talented and motivated pioneers to join our mission. View all career opportunities here.
Are there volunteering opportunities at The Great Bubble Barrier?
At The Great Bubble Barrier, we are always looking for helping hands. Get in touch with us to discuss possibilities. We might acquire your CV.
Are there internship opportunities at The Great Bubble Barrier?
We would love to work with you. All the available internships are listed on our Careers page.
Support, Funding & Donations
How can I support your mission and donate?
Thanks for your interest in supporting our bubbly mission. Check out our donation page to see how you can contribute!
Is The Great Bubble Barrier a non-profit or ANBI?
No, The Great Bubble Barrier operates as a social enterprise.
We chose this model instead of a non-profit in order to blend our mission of tackling plastic pollution with the flexibility and sustainability of a business model.
By functioning as a limited company (Besloten Vennootschap – B.V.) in the Netherlands, we can attract investments, foster continuous innovation, and more effectively scale our impact. This structure allows us to generate revenue, reinvest in our technology, and expand our reach to clean more rivers worldwide.
As a social enterprise, we stay true to our environmental mission while ensuring financial sustainability, which ultimately enhances our ability to make a long-term difference in the fight against plastic pollution. Our commitment to the mission of plastic-free rivers is legally embedded in our founding principles and investment approach.
Contact
I have suggestions and/or feedback, can I contact you?
Of course! We will happily receive any questions, suggestions or feedback you may have. You can leave a message via the contact form and we will contact you as soon as possible.
Can I visit a Bubble Barrier?
Yes, you can visit Bubble Barrier Amsterdam in the Westerdok, both virtually and physically.