Comparison of standardized methods for suspended solid concentration measurements in river samples

Comparaison de méthodes standardisée de la mesure de concentration solide dans des échantillons de rivières

Guillaume Dramais (1) , B. Camenen (1) , Jérôme Le Coz (1) , Fabien Thollet (1) , C. Le Bescond (1) , M. Lagouy (1) , A. Buffet (1) , F. Lacroix (1)

1 RiverLy - Fonctionnement des hydrosystèmes

SSC (Suspended Solid Concentration) measurements in rivers are a complex scientific issue. Many questions arise on the spatial and temporal distribution of particles throughout a cross-section, on the properties of particles and grain-size, and also on the sediment transport capacity of streams and rivers. In this study, we focused on the SSC and grain size distribution measured from river samples, automatically or manually acquired. Many agencies suggested slightly different methods for measuring SSC: The European standard NF EN 872, which related to the US EPA 160.2 requires sub-sampling using shake-and-pour aliquot selection. The APHA 2540D requires sub-sampling by pipetting at mid-depth in the original sample shaken with a magnetic stirrer. These methods lead to significant uncertainty when particles larger than 63 µm are present in the samples. The ASTM D3977 analysis method, endorsed by the USGS is more accurate to capture and quantify particles larger than 63 µm. In this study we confirm the sub-sampling problem in a large concentration range using a set of samples from an alpine river.

Mots clés: metrology; rivers

Mots clés: METROLOGIE; ECHANTILLON; COURS D'EAU

Domaines: Sciences de l'environnement

Guillaume Dramais, B. Camenen, Jérôme Le Coz, Fabien Thollet, C. Le Bescond, et al.. Comparison of standardized methods for suspended solid concentration measurements in river samples. River Flow 2018: 9th International Conference on Fluvial Hydraulics, Sep 2018, Lyon, France. 8 p. ⟨hal-01930679⟩