Litter in French urban areas-part 1: composition, sources, and spatio-temporal variations on urban surfaces.

Urban areas concentrate on human activities that generate large amounts of waste. A small fraction is mismanaged and ends up on urban surfaces and eventually in waterways. The fraction reaching waterways is usually estimated using poorly constrained data, while litter density on urban surfaces and its subsequent transfer dynamics are also poorly documented.

Litter in French urban areas - Part 2: transport dynamic and fluxes in stormwater.

Urban areas constitute a major hotspot of litter, including plastic litter, that stormwater can wash off towards waterways. However, few studies quantified and characterized litter densities in urban areas and fluxes transported by stormwater networks. Moreover, little information is available on litter transport dynamics in stormwater, and on the factors driving this transport.

Macrolitter dataset from a highly frequented roadway in Nantes, France.

Land-based sources of riverine macrolitter are now recognized as a major concern, but few field data on litter amount, composition and sources are available. This is especially the case for macrolitter hotspots like high frequented roadways that could generate large amount of macrolitter potentially reaching rivers. This dataset provides macrolitter amount and composition over one year from a retention pond collecting stormwater and carried macrolitter from a 800 m portion of a highly frequented roadway (around 90,000 vehicles per day).

Amount, composition and sources of macrolitter from a highly frequented roadway.

Many researches mention the need to identify the land-based sources of riverine macrolitter but few field data on litter amount, composition and sources are available in the scientific literature. Describing macrolitter hotspot dynamics would actually allow a better estimation of fluxes in the receiving environments and a better identification of the more appropriate mitigation strategies. This study provides new insights in roadway macrolitter production rates, typologies and input sources (i.