Pont-et-Massène. "The season is over": swimming has been banned at Pont Lake since Thursday afternoon
On Friday morning at Lake Pont, it wasn't just the mayor of Pont-et-Massène who was in a gloomy mood. Even the sky was gloomy.
"Yesterday [Thursday, July 31, Editor's note] at noon, we noticed that the level of Pont Lake had just reached the mark: 17.70 meters, which means that if the lake's mark is lower than that, swimming is prohibited," explains Patrick Roux, mayor of Pont-et-Massène. "So I immediately took the decision to post the prefectural decree concerning the site's regulations."
This document stipulates the conditions for using the lake, both for swimming and for boating and fishing. "I contacted the dam operator, who told me that the water was going to go down again. We had to anticipate, so I posted this order," continues the elected official, who reinforced the posting with "No swimming" signs installed in several places on the lake's beach. "It's not a ban on swimming, but those who do so do so at their own risk because it's dangerous because of the slope. When you enter the water, there's a second, steeper slope, and suddenly, children can't touch the bottom. Fishing, however, is still permitted."
For Patrick Roux, this swimming ban could have been avoided. "Voies navigables de France (VNF) [responsible for the dam located downstream, editor's note] took the decision in March to empty between two and three million cubic meters due to the work to be carried out at the Pinard bridge in Semur-en-Auxois . For the safety of the workers, it was necessary to lower the level, that's for sure, and take precautions, especially in the event of a storm, but to lower it to this extent, for me, is unprecedented. Is it reasonable? And was it wise to do it at this time? Three million cubic meters, that represents 3 meters [less, editor's note] at the Pont lake! I wasn't even warned," laments the first mayor.
"Because of the work to be carried out in Semur-en-Auxois following the 2024 floods, we wanted, for safety reasons, to keep the lake as low as possible. In one week, it went from 20 to 16.40 meters," explains Jacques Manière, president of the association "Un lac de Pont à la hauteur" . "The problem with the lake is that it is very steep; it has a particular topography." For Catherine Sadon, mayor of Semur-en-Auxois: "There needs to be a concerted improvement, between all the stakeholders, in the management of the dam."
"In this story, no one anticipated the summer season at Lac de Pont, or VNF was overconfident about the weather. It's unfortunate because it's ruined," laments the elected official. He adds: "We started the season at 18 meters when normally, when we launch it, it's at 21 meters. It was obvious that we weren't going to last more than a month. What saved the month of July was that there was no need to supply the Burgundy Canal."
Patrick Roux is now worried about the site's activity. " We have the campsite , the restaurant, etc. We know that with swimming prohibited, families won't come. There may even be an impact on the campsite because we're selling a service: customers are 50 meters from the lake where they can do activities. Since the beginning of the season, the nautical club has not been able to allow water skiing , electric boats and pedal boats due to the water level being too low. Only kayaking and paddleboarding are possible from 2 p.m. to 7 p.m. What saves the day a little is that the town organizes a sort of festival all summer long, with entertainment and concerts," the elected official tempers.
"Some residents aren't leaving. Pont Lake is their holiday destination. The municipality even took over management of the beach on January 1st [previously managed by the Terres d'Auxois community of communes, editor's note] and installed a fast food hut there."
For VNF, "the water levels of the reservoir dam have been managed exceptionally well this year."
The communications department of VNF, the manager of the Pont-et-Massène reservoir dam, states: "The water levels of the reservoir dam were managed exceptionally well this year. This is explained by a series of works carried out on the dam last winter: annual maintenance work on the structure's operating components to ensure its functionality, creation of a boat launch for fishing, and the work undertaken by the municipality of Semur-en-Auxois on the retaining wall of the Rue Chaude quay - this work was carried out in the very bed of the Armançon River. The priority was therefore to coordinate the management of the dam's water levels with the municipality, so as to ensure the safety of the workers. During the week, when the construction site was active, VNF ensured that only the flow reserved for the Armançon was allowed to flow out of the dam. On weekends, the dam level was lowered in a progressive and controlled manner."
A rainfall deficitHe added: "This situation was compounded by a rainfall deficit in the spring, followed by a heatwave. These weather conditions did not allow the reservoir's resources to be fully replenished. And the evaporation caused by the temperatures accelerated the drop in the water level, between 2 and 3 cm per day of the heatwave. We are well aware that this situation has an impact on recreational use around the reservoir. This is why water resource management since the beginning of the season has taken into account the exceptional management during the winter. The level of the structure will rise significantly if weather conditions permit. The reservoir's operating level is 21.03 m. It is currently at 17.7 m, which represents a loss of 3.33 m, equivalent to 2.3 million m3 of water," confirms VNF.
VNF specifies that two studies are underway on the Pont-et-Massène reservoir dam : "a study on the overall development of the site, the objective of which is to better coordinate uses on and around the body of water [...] and a more technical study on the evolution of the methods of managing the water stored in the reservoir dam in the context of climate change."
Finally, the manager announces that "on the initiative of the Prefect of the BFC Region, a works committee will be formed with all users and local authorities to better share the conditions for water management for the different uses."
Le Bien Public
