There is way less plastic being dumped into the ocean by rivers than we thought—like, 98% less.
SSRN · March 18, 2026 · 6433763
The Takeaway
Most global policies assume rivers are high-speed 'conveyor belts' for trash, but new tracking data shows they are actually long-term 'sinks' where plastic stays trapped for years. The study found that rivers only flush their plastic contents during very brief, rare windows of time, meaning our current understanding of global plastic pollution is fundamentally inaccurate.
From the abstract
Rivers are key pathways for plastic pollution to the ocean, yet global river export models remain highly uncertain due to catchment diversity and the complexity of plastic transport. We examined the critical river-ocean interface using a comparative dataset from three rivers in the Caribbean, Southern Africa, and Southeast Asia with distinct hydrometeorological and tidal regimes. We traced 196 GPS drifters and monitored surface transport at six river locations using forty-one cameras over multip