A device that traps waste
D-Rain is a system that recovers waste circulating in rainwater networks before it ends up in the sea. Attached to an outlet, a pipe that collects and evacuates rainwater, the system consists of a collar and a net that traps the detritus carried by the water flow.
At the origin of the innovation, Isabelle Gerente confides to us: " As a recreational and professional diver, I noticed, like many others, the degradation of the marine environment in which we evolve daily. We then decided, with my partner Thierry Dubourdieu, to found Green City Organisation, in order to bring our stone to the enormous cleaning up work that the future generations will have to manage. "
" During major rainy episodes, coastal cities discharge waste-laden rainwater directly into the sea without treatment via land or underwater outfalls. This is all the waste that litters our streets, sidewalks and gutters, which is discharged into the sea like a real flush. We then imagined the D-Rain system which can capture all waste smaller than 5 mm, including cigarette butts !"
Simplified monitoring and emptying
The D-Rain system does not retain water and does not burden the drainage system. Real-time monitoring of the filling level of the net is possible thanks to several sensors.
Nevertheless, in case of overflow of the device, a valve releases the water flow in order to preserve the drainage network.
The complete emptying of the device is done in 20 minutes. A truck crane is positioned above the outlet and empties its contents, which will then be sorted by the actors of the sector. The D-Rain is then put back in place and resumes its collection immediately.
A prototype that has proven its efficiency
A D-Rain device was installed on the Old Port of Marseille in December 2021. Thanks to the support of the club La Nautique, which was able to mobilize local partners, the D-Rain has been installed on a 4 m by 3 m outlet located on the Rive Neuve quay.
Despite a year of drought with very little rainfall, the D-Rain collected more than 10 tons of waste of all kinds.
A system that must be generalized
10 tons of waste collected from a single outlet is a huge quantity. This disturbing fact highlights the interest of the device, which interests many neighboring countries, the Mediterranean being one of the most polluted seas in the world. Water network managers are interested in the system, but also harbourmasters' offices and marina owners.
