The reed bed filters for runoff treatment: Efficiency notion

Valérie Giroud *, Dirk Esser *, Laëtitia Fournet *, Frédéric Davoli **
* SINT, 5 rue Boyd – 73 100 Aix les Bains – France,
** EPFL, 1015 Lausanne – Suisse,


Constructed wetlands as reed bed filters, widely used for sewage treatment, have recently become an interesting alternative for runoff treatment and retention. Started up in spring 2002, this filter set up at Neydens, near the border between France and Switzerland, collects runoff from national road n°201 (whit and average daily traffic flow of approx 18 000) and parking. The filter was monitored between May to September 2004. The physical and chemical parameters analysed have shown a large fluctuation following the events. The average removal efficiency of this system for TSS was 95%, 69% for COD, 78% for zinc, 81% for lead, 21% for cadmium and 82% for total hydrocarbons;

Dirk ESSER  
Société d’Ingénierie Nature & Technique
F-73370 La Chapelle du Mont du Chat
Tél.: + 33 (0)6 07 21 61 07