Plastic waste and abandoned fishing nets are being given a second life in Hawaii. Researchers at the Hawaii Pacific University’s Center for Marine Debris Research are now incorporating these materials into asphalt mixtures for road paving.
This initiative is being carried out in partnership with the Hawaii Department of Transportation. Since 2020, most of the state's roads have been built using polymer-modified asphalt, which is specifically designed to withstand the tropical climate. Now, a portion of the virgin SBS polymer is being replaced with recycled polyethylene derived from household waste and discarded fishing gear.
A team led by Jennifer Lynch conducted field trials on a residential street in Oahu to test the new material. The road was divided into sections using three different mixtures: a standard control, one containing recycled polyethylene from local waste, and a third featuring material from ocean-recovered nets. After 11 months, they collected road dust for analysis using pyrolysis-gas chromatography-mass spectrometry.
The results are encouraging, indicating that pavements containing recycled plastic do not release any more microparticles than conventional asphalt. The analysis revealed that tire wear, rather than the plastic in the road surface, is the primary source of polymers in the dust. Because the plastic bonds securely with the bitumen, any particles that do break off remain attached to the stone and binder.
The Bounty Project has already successfully removed 84 tons of large-scale marine debris from the Pacific Ocean. Repurposing these materials for infrastructure projects reduces the strain on local landfills and lowers the high costs associated with transporting waste off the islands.
While the long-term durability of these new roads will be monitored through ongoing testing, the initial phase has been a success. The project demonstrates that recycling can be highly effective when a society prioritizes sustainability. Does this mean it is time to start pursuing similar solutions for other regions?
Jeremy Axworthy presented the study's findings at the American Chemical Society’s spring 2026 meeting. The research was funded by the Hawaii Department of Transportation.
