MAINTENANCE AND RESTORATION OF WATERWAYS

The watercourse has a complex function, it not only allows the flow of water and sediment from upstream to downstream, but it also fulfills an ecological and economic role (drainage, irrigation, fishing, fish farming, etc.). ) and heritage. Drainage Maintenance Services provides many services to society, including facilitating flood management and preventing erosion, participating in the physicochemical purification of water, and allowing the reproduction, growth, and life of aquatic and fish species.

A regulatory obligation

The maintenance of waterways is, therefore, a technical and regulatory necessity for professionals and users. The Environmental Code defines and the obligations and authorized practices for the regular maintenance of waterways. It is a question of “maintaining this watercourse in its equilibrium profile, allowing the natural flow of water and contributing to its good ecological state or, where applicable, to its good ecological potential, in particular by removing jams, debris and landfalls, whether floating or not, by pruning or cutting back vegetation from the banks”.

If the Drainage Maintenance Services owners have the regulatory obligation to carry out. These maintenance operations, this practice tends to be lost. And the community must therefore replace them to allow the free flow of water. To pool this maintenance of rivers, the municipalities have grouped. Into groups of municipalities (SIVU, Syndicat mixte, etc.). Also called river syndicates, which also sometimes work to prevent the risk of flooding, restore the banks, etc. . Work carried out by local authorities on private plots is subject to a declaration. So general interest (DIG), except in the event of an emergency.

The Adour Garonne Water Agency

The management of vegetation and ice jams is a major focus of SIGOM’s activity. It is finance mainly by the Adour Garonne Water Agency, the Region, and the Department. Communal participation is mutualize among all communes.

The aquatic and riparian vegetation plays an important role in the stability of the banks, the limitation of invasive vegetation, and the protection and the life of the aquatic environment. It is therefore important to manage this vegetation to limit erosion phenomena.

The maintenance of the vegetation remains a delicate operation. It should not be systematic but only to allow the flow of water, to improve. So the state of the riparian forest, limit the invasive species, or to prevent the risks. of ice jams. While taking care to preserve a minimum of shelters and habitats for aquatic fauna.

This leads to considering two main families of interventions

Targeted treatment of certain subjects: pruning, coppicing, felling, etc.
Non-intervention and the reconstitution of a suitable portion of the riparian forest: spontaneous regeneration, cuttings, planting.