Title of the dataset:
Floating litter in the Dutch Rhine-Meuse delta 2021

Creators:
Tim van Emmerik
Sjoukje de Lange

Contributors:
Roy Frings, Louise Schreyers, Heleen Aalderink, Joshua Leusink, Finn Begemann, Eric Hamers, Rahel Hauk, Peter Jansson, Niels Janssens, Nonna Joosse, Dana kelder, Tim van der Kuijl, Romi Lotcheris, Ansje Löhr, Yvette Mellink, Rose Pinto, Paolo Tasseron, Vivien Vos, Paul Vriend, Tom Barendse, Boaz Kuizenga, Jiaheng Zheng, Titus Kruyssen, Belle Holthuis, Aline Looijen, Siebolt Folkertsma, Lianita Suryawinata, Kryss Waldschläger, Anna Schwarz, Rosalie Mussert, Lisanne Middelbeek, Roos Kolkman, Joël Kampen, Gijs Roosen, Evelien Castrop, Maartje Wadman, Olga Dondoli, Khoa Thi, Wessel van der Meer, Tijme Rijkers, Laura Wilson, Berte Mekonen, Willen de Rooij, Pepijn van Aubel, Lauren Quiros, Ida Meyenberg.

Related publication:
Hydrology as driver of floating river plastic transport

Description:
We measured floating plastic and other anthropogenic litter at 26 measurement locations distributed across the Dutch reaches of the Rhine (IJssel, Waal, Nederrijn) and Meuse rivers (see Figure 1) between 28 January and 7 December, 2021. The Rhine enters the Netherlands from Germany at Spijk, and splits into the main Waal, IJssel and Nederrijn. The Waal is the main branch, and joins the Nederrijn-Lek branch at Rotterdam before flowing into the North Sea. The IJssel flows into Lake IJssel at Kampen. The Meuse enters the Netherlands from Belgium at Eijsden, and discharging into the tidal Hollands Diep estuary. Here, the Meuse is joined by a Rhine distributary before reaching the North Sea.

Floating macroplastic and macrolitter (>0.5 cm) were measured using the visual counting method, for which all items floating at the surface are counted from bridges. Only bridges that are safe and legally accessible, e.g. presence of pedestrian or bicycle paths, were selected. At each location, three to twelve observation points were selected, depending on the river width. The majority of the locations had five or six points (23 out of 26), two locations had three points, and only the downstream Meuse location had twelve points. For a measurement, all visible floating items were counted within a predefined observation track. The minimum observable item size depends on the bridge height (8-20 m), but was estimated to be at least 2.5 cm for all locations. Note that the width of the observation tracks depends on the field of view and the height above the water, and there varied between bridges and between points on the same bridge (12-34 m). The observation track width was quantified by selecting a reference object (e.g. bridge column, buoy, orange peels) and measuring the distance to the observation point. The sum of the observation track widths per bridge covered between 25% and 85% of the total river width. On each measurement day each point was measured four times for a five-minute period.

Keywords:
Plastic pollution
Macroplastic
Microplastic
Hydrology
Rivers

Spatial coverage:
Dutch branches of the Rhine, Meuse and IJssel rivers.

Temporal coverage:
January to December, 2021

This dataset contains the following files:
Dataset01_Brugtelmetingen_2021_van Emmerik en de Lange.xlsx


Explanation of variables:
Bridge width: total width of the brigde [m].
Segment: segment on the bridge (3 to 12, depending on the bridge).
Segment width: width of the obesrved segment [m].
Duration: duration of the measurement [min].
PET...Other: counted items belonging to that categoryduring the measurement.
Total counted: Total counted items during the measurement.
Item flux: Normalized item flux in items/min, items/hour, items/hour/m.
Extrapolated items/hour: normalized item flux extrapolated to hourly values and to the total river width.


Methods, materials and software:
https://doi.org/10.3389/fmars.2018.00372

This dataset is published under the CC BY (Attribution) license.
This license allows reusers to distribute, remix, adapt, and build upon the material in any medium or format, so long as attribution is given to the creator.

