Effects of a sewage treatment plant outlet pipe extension on the distribution of contaminants in the sediments of the Bay of Vidy, Lake Geneva, Switzerland

• Published in: Bioresource technology Vol. 99; no. 15; pp. 7122 - 7131
• Main Authors: Poté, John, Haller, Laurence, Loizeau, Jean-Luc, Garcia Bravo, Andrea, Sastre, Vincent, Wildi, Walter
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 01-10-2008; [New York, NY]: Elsevier Ltd; Elsevier
• Subjects: Biological and medical sciences; Freshwater; Fundamental and applied biological sciences. Psychology; Geologic Sediments - chemistry; Heavy metals; Lake Geneva; Micropollutants; Sediments; Sewage; Sewage treatment plant; Switzerland; Water Microbiology; Water Pollutants - analysis; Central Europe; Switzerland; Europe; Switzerland, Vaud, Leman L; Micropollutants; Sediments; Lake Geneva; Heavy metals; Sewage treatment plant; Micropollutant; Bay; Pipe; Contaminant; Heavy metal
• ISSN: 0960-8524; 1873-2976
• DOI: 10.1016/j.biortech.2007.12.075

In 2001, the municipality of Lausanne extended the outlet pipe of the sewage treatment plant into the Bay of Vidy (Lake Geneva, Switzerland) as a measure to reduce bacterial water pollution and sediment contamination close to the lake beaches. The aim of the present study was to assess the impact of this measure. Lake bottom sediments were collected and analyzed for grain size, organic matter, organic carbon, nitrogen, phosphorus, heavy metals and hydrophobic organic compounds to evaluate their concentration and spatial distribution. Our results demonstrate that, compared to results obtained before the outlet pipe prolongation, the surface area of highly contaminated sediments was reduced by one third after the pipe extension. However, contaminant concentrations are still high and the accumulation of pollutants may represent a significant source of toxicity for benthic organisms. One concludes that contaminant reduction at the source will be necessary for a further improvement.