Research

My research project focuses on the physical and chemical impact of the third River Rhone Correction (R3) on groundwater. The project is funded by the Valais canton and the Swiss confederation.

The development works of the 3rd Correction of the Rhone River will locally impact the colmation layer of the river bed. A deepening of the bed implies the partial or total removal of the clogging layer, while a widening of the bed implies the flow of the river over an initially non-clogged bed. Moreover, the development of a dynamic river bed morphology in riffles and pools is likely to reduce chronically or permanently the clogging of the bed. The alteration of the colmation layer will locally induce higher infiltration rates, greater mixing of surface and subsurface water and increased transport speeds towards the wells exploiting the aquifer in the vicinity of the river, with possible impact on their vulnerability. Moreover the artificial lowering of the water table, via the pumping and discharge of groundwater in the Rhone river, can prove problematic in the case of polluted groundwater.

One of the main objective of the project is to improve the understanding of the river bed clogging dynamic in order to better predict the impact of R3 on groundwater.

The project mixes several approaches among which:

• The analysis of times series of surface and sub surface water (discharge, head, temperature, electric conductivity and turbidity)
• The mathematical simulation of clogging,
• The punctual investigation of river bed conductivity and granulometry,
• And the assessment of existing groundwater quality data in order to study.

Publications

Samuel Diem, Olivier Masset, and Joachim Poppei. Using natural tracers for transport model calibration. In FEFLOW 2015 Conference, 2015.

Sarah Jane Fowler, Georg Kosakowski, Thomas Driesner, Dmitrii A. Kulik, Thomas Wagner, Stefan Wilhelm, and Olivier Masset. Numerical simulation of reactive fluid flow on unstructured meshes. Transport in Porous Media, 112(1) :283–312, Mar 2016. ISSN 1573-1634. doi : 10.1007/s11242-016-0645-7.

Simon Loew, Volker Luetzenkirchen, Juergen Hansmann, Olivier Masset, and Peter Guntli. Bergwasser zuflüsse zum gotthard basistunnel und hydromechanisch gekoppelte deformationen im gotthard-massiv. In Tunnelling the Gotthard, pages 406–413. FGU Fachgruppe für Untertagbau, 2016.

Olivier Masset. Transient tunnel inflow and hydraulic conductivity of fractured crystalline rocks in the Central Alps (Switzerland). PhD thesis, ETH, 2011. Olivier Masset and Simon Loew. Spatial distribution of tunnel inflows in the central aar and gotthard massifs (switzerland). In XXXV Congress of the Iinternational Association of Hydrogeologists, Groundwater and Ecosystems, 2007.

Olivier Masset and Simon Loew. Hydraulic conductivity distribution derived from inflows to tunnel and galleries in crystalline rocks (central alps, switzerland). Hydrogeology Journal, 2010.

Olivier Masset and Simon Loew. Quantitative hydraulic analysis of pre-drillings and inflows to the gotthard base tunnel (sedrun lot, switzerland). Engineering Geology, 2013.

Olivier Masset and Joachim Poppei. Application examples of pilot point calibration with feflow and pest. In FEFLOW 2012 Conference, 2012.

Olivier Masset, Laurin Wissmeier, Joachim Poppei, and Frank Wenderoth. Transport of radionuclides in the overburden of a flooded salt mine. In FEFLOW 2015 Conference, 2015.

Patrice Moix, Laurent Beccaletto, Olivier Masset, Heinz W. Kozur, Paulian Dumitrica, Daniel Vachard, Rossana Martini, and Gérard Stampfli. Geology and correlation of the mersin mélanges, southern turkey. Turkish Journal of Earth Sciences, 2011.

Office: E308

Tél.: +41(0) 32 718 26 45

[email protected]

Centre for Hydrogeology and Geothermics (CHYN)
Emile-Argand 11
CH-2000 Neuchâtel

​