Since the impoundment of the Serre-Ponçon dam in the 1960s, the tail of the reservoir has been subject to significant sedimentary deposits as the Durance River floods. These poorly cohesive materials are easily suspended in the air as soon as the first valley breezes appear in spring. In addition, the Serre-Ponçon hydroelectric reservoir is subject to a significant tidal range during its annual operating period: in winter, the lake is progressively emptied to meet energy needs, and the tail of the reservoir is left dry.
These combined phenomena give rise to veritable clouds of dust (known as "sand winds"), causing considerable nuisance for local residents. Once suspended in the atmosphere, they often spread up the Durance valley. A total area of 15 hectares is affected by these unpleasant phenomena.
The issue of "sand winds" is a very serious one, calling for solutions that are unfortunately still unknown to date, despite the many tests carried out by the S.M.A.D.E.S.E.P. and EDF Hydro Méditerranée: underground sprinkler systems, vegetation on flooded terraces, lowering of shoals, watering by tanker trucks, etc.
In this context, the management of sediments deposited each year by the Durance in the tail of the Serre-Ponçon reservoir, linked to the inexorable filling in of this sector of the lake, reinforces the interest in a long-term system for reclaiming silt, whose deposits are estimated at 600,000m3 per year[1].
The creation of an industrial sector for the production and marketing of garden soil from the nite present in the tail of the Serre-Ponçon reservoir would be an initial favorable response.
This project would meet two main objectives:
To promote the establishment of an industrial sector linked to the exploitation of a local and abundant resource,
Develop innovative solutions to reduce the impact of sandstorms on the local population,
Find an outlet for the driftwood brought in each year by the Ubaye and Durance rivers, through shredding and composting processes (the economic value, even partial, of the overall system would also enable us to mobilize the resources needed to sort this wood, which is regularly polluted by non-organic waste).