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Amongst the numerous retention ponds alongside motorways from the French concession motorway company ASF, this study focused on a pool of 18 ponds in the South-East of France. The purpose was to determine the major features of the pond functioning beyond structural characters, biotic and abiotic environmental parameters and evaluate the remediation potential of the spontaneous flora. Results showed that water chemistry was not a discriminant pool of data because these parameters were under control of water renewal. However, among the sediment chemical parameters selected, carbonate content was a good discriminant. Pond vegetation showed a classical dynamic of evolution with helophytes following hydrophyte colonization. Amongst the plant taxa, Chara vulgaris was more abundant in carbonated ponds while Chara globularis occurred in less carbonated ponds. A rhizospheric effect was demonstrated enhancing trace elements biodisponibility. However no metal hyperaccumulation was observed in the analysed aquatic plants. Metal contents in plants were low compared with metal contents in sediments. The highest metal accumulation was obtained in roots of typha. Even if charophytes produced high biomass in the ponds, low levels of trace elements were accumulated in plant tissue. However, plant cover play a stabilization role in the ponds: regarding strong gusts of wind, typical of Mediterranean climate and possible pollutant dispersion, vegetation may improve particles trapping in the ponds.