As part of the rehabilitation of the Saint-Martory sur la Garonne roadway, IVEA once again demonstrated the relevance and efficiency of its patented gravity closure system, this time for a screen to be lowered under the effect of its weight in the event of a power failure. A security imperative to guarantee the region's supply of drinking water....

To meet highly strategic challenges....

Through the Saint-Martory Canal, the Saint-Martory causeway meets highly strategic challenges: drinking water supply for more than 200,000 inhabitants, irrigation for more than 10,000 hectares, fire protection supply, support for the low water level of tributaries (the Louge and the Touch) and hydroelectric power supply through the operation of 5 waterfalls.

Driven by Network 31 (Syndicat mixte de l'eau et de l'assainissement de la Haute-Garonne), carried out under the project management ofEGISthe rehabilitation work completed in 2019 was aimed at:
- on the one hand, to secure the Saint-Martory causeway against geotechnical hazards and river erosion;
- on the other hand, to restore ecological continuity, with the creation of a devaluation arm and fish crossing structures.

... An ingenious and specific patented solution

The planned improvements included the redevelopment of a devaluation pass equipped with a screen. This valuable filtering equipment is tilted 15° by means of hydraulic cylinders, which lower the screening plane at the bottom of the channel if the upstream water level alert threshold is exceeded.

But in case of accumulation of dirt, the power failure can occur and block the device in the raised position, without the possibility of cutting off the water supply! It was there that IVEA was able to demonstrate its expertise through its patented solution to, as a last resort, "break this problematic lock": a specific device - based on motorized coupled jacks, reversible servomotor and braking module - allows the grid, in the event of a power failure, to descend gravitarily under the effect of its own weight, and this at a speed controlled by a variator.

An ingenious and particularly welcome security system, given the major operational challenges mentioned. And the proof that gravity closure is not only reserved for valves (see our references in Haute-Garonne, in Italy...): many other structures and equipment can use this basic principle to prevent or solve safety problems that can occur without having electrical energy...