Description : This project focuses on the transfer dynamics of contaminants from the coastal zone to the deep zone of mid-size lakes (at the global level). It consists principally of 3 sub-projects concerning more particularly:

1. The dynamics of the water masses in Lake Geneva, with a particular attention in the bay of Vidy, off the city of Lausanne,
2. the transformation and the dynamics of transport of contaminants,
3. the sediment dynamics between the coastal area and the deep zone, in particular the focusing processes.

Framework/Financing: The project is funded by the Swiss science foundation, in the framework of the ProDoc action ProDoc « Scientific concepts for the sustainable management of mid-size lakes in the 21st century », headed by the prof H. -R. Pfeifer. It allows the engage 3 doctoral students.

Collaborations : This project is implemented with a direct collaboration with Prof. A. Barry of the EPFL, while the overall project ProDoc is a collaboration of the universities of Lausanne and Geneva, from the EPFL and of the Eawag.
Supervisor and colleagues directly involved : J.-L. Loizeau, W. Wildi, J. Dominik, A.D. Le

Research module 4: Project 4

The sediment contamination by heavy metals, faecal indicator bacteria and other micropollutants such as hydrophobic organic compounds and antibiotics remain active research fields since the global, regional and local pollution of water still represents a potential hazard for human and ecosystem health. Typical examples for contaminated surface waters in Switzerland are the Bay of Vidy (City of Lausanne) and the Wettingen reservoir (on the Limmat River). In both cases, the role of sediments as substrate and reservoir is of great importance. Also, the problem has been studied during the last years but many questions still remain open. These are in particular: (1) persistence and remobilization rate of contaminants in the sediment; (2) interaction between biotic and abiotic processes affecting accumulation and release of contaminants from the sediments;,(2) potential adverse effects of sediment contaminated by heavy metals, human pathogens and organic pollutatnts (e.g. PCBs, PAHs,OCPs) and antibiotics for ecosystem and human health. In the ProDoc project, we propose to study the above mentioned questions with the following objectives: (1) determining the heavy metal and antibiotic resistance patterns of bacteria; (2) determining the effects of bacterial activities on the release of heavy metals from contaminated sediments to water column; (3) assessing the effect of sediment toxicity on the microbial community and the potential for biological effects; (4) determining seasonal environmental parameters affecting the distribution of the contaminants and evaluating water quality and risk for human health during recreational activities.