Mechanics of Plastic Transport

Contact: Daniel Valero and Mario Franca


The transport of plastics in rivers remains a poorly understood phenomenon, hindering the development of predictive models for plastic fate and the identification of areas where plastics sink, accumulate, or infiltrate.

Current plastic pollution is unprecedented and there is increasing concern by toxicologists about potential impacts of plastics in humans, animals and plants. With recent studies, we have shed light on the floating and surfaced transport of plastics (Valero et al., 2022), and on the interaction of plastic particles travelling as bedload with the channel bed. However, little is still known about many aspects of bedload transport, which can account for up to 50% of total plastic transported by rivers, settling and rising and the resuspension, material dependency, scaling and many other aspects of the mechanics of plastic transport in rivers. We investigated the physical processes involved in the transport of plastics in rivers, aiming ultimately at the development of functional, predicting models for the transport of plastics under fluvial conditions, throughout the water column and across the scales of plastics.



Valero, Daniel, Biruk S. Belay, Antonio Moreno-Rodenas, Matthias Kramer, and Mário J. Franca. "The key role of surface tension in the transport and quantification of plastic pollution in rivers." Water Research 226 (2022): 119078:

Lofty, James, Daniel Valero, Catherine AME Wilson, Mário J. Franca, and Pablo Ouro. "Microplastic and natural sediment in bed load saltation: material does not dictate the fate." Water Research 243(2023): 120329:


This project is a collaboration between:

  • Karlsruhe Institute of Technology
  • Imperial College London (UK)
  • Cardiff University (UK)
  • University of Manchester (UK)


Mechanics of Plastic Transport
Figure 1 –Forces driving the transport of plastics in river flows. Elements considered in Valero et al. (2022)