How Amsterdam’s Bubble Barrier Removes About a Tonne of Plastic a Year

Amsterdam’s water authority, Waternet, said on 16 September 2024 that the city’s Bubble Barrier catches about one tonne of plastic waste a year. Waternet said the test began in 2019 and that the installation will remain in place.

The system is designed to intercept floating plastic in a waterway. It does not use a solid screen across the channel. Instead, air is pumped through a perforated tube placed on the riverbed. The rising bubbles create an upward current that brings floating plastic toward the surface.

The tube is placed diagonally. According to the technology developer, the water’s natural flow then helps move the floating material to one side and into a catchment system. The waste can be collected after it reaches that catchment. This matters because interception systems have to work with the shape and flow of a particular waterway, rather than assume every river or canal behaves in the same way.

What Is Known From Amsterdam and the Earlier Pilot

UNESCO says an earlier 180-metre pilot was installed on the IJssel River in 2017. It also says the first long-term Amsterdam installation was ready in November 2019. UNESCO describes the same basic mechanism: air moving through a tube on the riverbed produces a curtain of bubbles that moves plastic upward, while fish and vessels can pass.

The developer reports a capture rate of 86% for floating plastic from pilot data. That figure should be read narrowly. It is the developer’s pilot-data result, not a guaranteed rate for every waterway. The developer also says each potential site needs its own assessment before installation. Flow conditions, the channel’s shape and the material moving through it can differ from place to place.

Waternet’s annual figure is a separate measure: about one tonne of plastic waste caught each year in Amsterdam, according to its September 2024 statement. It does not establish a general rate for other waterways, and it should not be confused with the developer’s pilot-data percentage.

Amsterdam’s experience shows why the distinction is useful. The confirmed public record is specific: a pilot history, a long-term installation, a bubble-based diversion method and an annual quantity reported by the local water authority. Those facts are more useful than broad claims about what the technology may achieve elsewhere.

Plastic pollution also depends on reducing waste before it reaches waterways. Karmactive has previously examined how plastic collection targets can require careful context. In Amsterdam, Waternet has said the Bubble Barrier will remain, giving the city an ongoing way to collect some floating plastic as part of its waterway management.