A hole formed in the Noyalo dam in November 2022. With a diameter of around thirty centimeters, it continues to increase in size. Obviously, this defect is closely monitored by the Gulf of Morbihan Vannes agglomeration water services (GMVA). The structure was built in the early 1960s and will require work, the extent of which has not yet been measured. The bridge ban on heavy goods vehicles and passenger transport will therefore last for quite some time. Just like the alternating circulation of cars and the closure of the parking lot. This traffic restriction is one of two measures taken to avoid accelerating the deterioration of the dam. “At the same time, our services work to keep the water level as constant as possible to avoid shocks to the structure. With the heavy rainfall that we experienced, there was a lot of power outage,” explains Gaëlle Le Roux, head of the water service at the city.
At least a year and a half to wait
The Noyalo water reservoir plays a major role for the entire Vannes area. The pond contains 2.5 million cubic meters of water and its surface covers 140 hectares. Four sources feed it. It allows the drinking water plant which is attached to it to cover a quarter of the needs of the 174,000 inhabitants of Gulf of Morbihan Vannes agglomeration (GMVA). “It supplies roughly all the municipalities located south of the RN165,” indicates Thierry Eveno, the elected official in charge of this issue at GMVA.
A call for tenders for a feasibility study of the redevelopment of the dam was launched by the community. Its goal is to ask a specialized firm to submit several work scenarios. If it turned out that the structure was in very poor condition, the most radical solution would be to have to build a new dam. But we’re not there yet. In the meantime, heavy goods vehicles and school transport buses are not about to use the bridge which serves Noyalo again. The results of the study are not expected for a year and a half…
