Hawaii Turning ‘Ghost’ Fishing Nets and Household Trash into Durable Asphalt Roads

New research from the ACS Spring 2026 meeting shows Hawaii is successfully recycling ocean plastic and fishing nets into asphalt without increasing microplastics.

By: AXL Media

Published: Mar 23, 2026, 5:21 AM EDT

Source: Information for this report was sourced from American Chemical Society (ACS)

Innovative Solutions for an Island Plastic Crisis

Hawaii faces a unique logistical challenge: the high cost of transporting waste off the islands and the environmental toll of incinerating plastic or dumping it into limited landfill space. To address this, the Hawaii Department of Transportation (HDOT) partnered with the Center for Marine Debris Research at Hawaiʻi Pacific University to investigate a circular economy solution. By incorporating "ghost" fishing nets—the largest contributor to Hawaii’s marine debris—and recycled household polyethylene into asphalt, the state is testing a way to sequester plastic waste in long-term infrastructure.

From Ocean Debris to Highway Pavement

Since 2020, Hawaii has utilized polymer-modified asphalt (PMA) to combat the cracking and rutting common in tropical climates. Traditionally, this involves melting virgin "SBS" pellets into petroleum-based binders. The new research, led by Jennifer Lynch and Jeremy Axworthy, replaces or supplements these virgin polymers with repurposed high-density polyethylene (HDPE). The project utilized 84 tons of derelict fishing gear removed from the Pacific through the "Bounty Project," which pays commercial fishers to retrieve marine debris.

Addressing the Microplastic Question

A primary concern for environmentalists was whether these "plastic roads" would shed more microplastics into the surrounding soil and stormwater than traditional pavement. To test this, researchers collected road dust from experimental sections of an Oahu residential road after 11 months of heavy traffic. Using state-of-the-art pyrolysis gas chromatography-mass spectrometry (Py-GC-MS), the team measured the chemical signatures of the polymers.