Multi-Level Approach of the Ecotoxicological Impact of a Combined Sewer Overflow on a Peri-Urban Stream

Abstract

In periurban zones, urban wet weather discharges have been recognized as the most significant vector of pollution in aquatic environments. The discharge of this water without treatment into the aquatic environment could present an ecotoxicological risk for biocenosis. The aim of the INVASION project is to assess the potential ecotoxicological impact of a combined sewer overflow (CSO) on a peri-urban stream. A comparative study between upstream and downstream areas of the CSO allowed observing significant effects of this overflow on the river. We studied three layers of stream: surface water, benthic layer and hyporheic layer. To characterize the potential ecotoxicological risk of water and sediments, we used a battery of 4 bioassays: Daphnia magna, Vibrio fischeri, Brachionus calyciflorus and Heterocypris incongruens. In parallel, we measured the physico-chemical parameters: ammonium ( ), chromium (Cr), copper (Cu) and lead (Pb). An ecological risk is greatest for the hyporheic zone in downstream river, particularly for the solid phase. These results corroborated with the physico-chemical data obtained. NH

Local influence of south-east France topography and land cover on the distribution and characteristics of intense rainfall cells

“…Much research has been conducted by the various teams participating at all levels of study: the characterisation of precipitations (Emmanuel et al 2012;Renard et al 2012;Lepioufle et al 2012), microbiology (Badin et al 2012;Maazouzi et al 2011) and the pollution of receiving environments (Becouze et al 2011;Becouze-Lareure 2012), and the hydrological modelling of the consequences of builtup areas Kouyi et al 2011). New themes include study of local effects on pluviometry, such as those related to urban environments (roughness, island of urban heat, pollution, albedo, etc.…”

Preliminary Toxicity Assessment of Combined Sewer Overflows in Toyama, Japan

“…The physicochemical approach highlighted the critical nature of some substances (Ptot, Al, total residual chlorine, Cr, Cu, pyrene, NH 4 + -N, Pb, and Zn). Becouze-Lareure [19] evaluated the ecotoxicological impact of a combined sewer overflow (CSO) on the Chaudanne, a periurban stream situated in a peri-urban drainage basin in the Lyon area of France. Not only chemical analysis methods, but also the ecotoxicity risk assessment method of four kinds of aquatic organisms were used to compare the impact of upstream and downstream of rivers evaluated the CSOs.…”

“…Among the four organisms used to assess the CSOs, only two aquatic organisms showed chronic toxic effects. Combining the results of chemical analysis, it is reported that the CSO might influences the ecosystem of the watershed [19].…”

Flood risk management centred on clusters of territorial vulnerability

“…Although numerous focused studies have been made of the hazards (physical phenomena of a given nature, intensity and occurrence) linked to these risks in the Lyon area (Kouyi et al 2011;Becouze-Lareure 2012), publications on the vulnerability of Greater Lyon are rare. In fact, after being based historically on the control of hazards, risk management has recently addressed Step-by-step procedure for a territorial vulnerability clustering process.…”