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The sinking of the Loire riverbed : a worrying problem

Restricting the living space of the river often induces the sinking of its bed, with all the harmful consequences this implies for the natural environment and water supply. Indeed, when the bed sinks, the water level logically drops. The main course of the river is cut off from the secondary branches. The riverine underground water level and the adjoining swamps dry up. The fish spawning grounds disappear, the riverine forests wither, commonplace vegetation overgrows the environment and water supply decreases. Works meant to fasten the riverbancks with rock dykes are currently one of the main threats to the Loire and Allier rivers’ living space. When its banks are dyked up with rocks, a river can no more erode them and refill itself with sediments. It then erodes its bed, which sinks. These dykes usually appear together with recreational activities, sandpits and intensive farming, which themselves destroy the natural environment and generate pollution. Actually, the damages done to the Loire natural heritage has many origins, which often add one to the other. The disturbances which ensue harm the whole human community.

The natural environment is varied
Water can flow from the river to the underground riverine water level
Natural erosion : the riverbed can refill itself with materials

Banks are dyked up with rocks
The riverbed sinks
The water flow speeds up

The underground water level sinks
Spawning grounds dry up
Riverine forests die
Commonplace vegetation overgrows
Activities generating pollution and vulnerable to floods appear

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