Lake Serre-Ponçon Resilience Plan

In progress

The resilience plan is the ambition led by SMADESEP. Its aim is to set a development trajectory for our Alpine reservoir, including the impact of global warming. In view of the pressure on water resources, the tourist economy generated in the two Alpine départements deserves to be secured in the long term.

The S.M.A.DE.SE.P. and EDF Hydro Méditerranée have joined forces with local and regional players to launch a new phase in this development, which they expect to be highly resilient.

Drought 2022 A threat to the economy and an opportunity for change.

The 2022 summer season was a perfect illustration of the impact of global warming. On a national level, this drought generated a significant water deficit, marked locally by a considerable drop in the level of Lac de Serre-Ponçon. As a result, the lake level was too low to ensure safe boating throughout the peak tourist season.

Despite careful winter management (the lake level never fell below -12m of water level, which is truly exceptional at a time when electricity prices are at record highs), EDF was unable to reach the optimum operating level (780 m NGF), or even the tourist-compatibility level (775 m NGF, or -5m of water level) that was the shared objective between July 1 and August 31. The large reservoir only reached 771.20 m NGF on July 1 (i.e. -8.90m), and -17m on August 31.

Despite emergency intervention by SMADESEP teams, a large majority of activity providers share a general assessment of the impact of an average loss of 30% of sales made on the Serre-Ponçon reservoir, as well as the extra work required to adapt practices to the low tide .

According to the scientific community, this exceptional phenomenon could recur more frequently. The reality of global warming is making Serre-Ponçon a more fragile destination.

EDF and the S.M.A.De.Se.P. are working hand in hand to ensure the lake's resilience. To this end, they have signed a specific agreement to launch a joint initiative open to civil society and involving the lake's many stakeholders.

A concerted, broad-based development phase. Combine to federate!

An operational process centered on consultation

The next step is to design the programming required to meet this resilience objective. Within this framework, 3 strategic areas of intervention are identified as ambitious for the retention area:

  • Combating global warming;

  • Adapting nautical infrastructures to the effects of global warming;

  • Diversification of the lake economy towards activities less dependent on lake levels;

The syndical committee is committed to the production of a resilience plan, providing for the information and consultation of the public (elected representatives, socio-professional players, representatives of civil society, residents, etc.) by means of dedicated tools and through ambitious planning:

  • October 2022: Publication of a brochure outlining the issues and objectives of the project (October 2022) .

  • December 2022 to January 2023: Implementation of a dedicated website to present the diagnosis of the sensitivity of tourist sites to tidal range and proposed actions (notably from the sustainable development plan deliberated in 2019, available below).

The aim is to gather the intentions of a broad public in order to collectively design the lake of tomorrow.

  • February 2023 : Nearly 500 questionnaires were collected and processed. The proposals were presented during an "institutional" phase, in particular to the Region, the State and the members of the S.M.A.DE.SE.P. (Départements + EPCI). These intentions validated almost all the proposals made. They conferred a great deal of legitimacy on the process, providing a great dynamic for its subsequent phases.

    Find out the results of this public consultation, which gathered the intentions of 492 respondents, below:

  • March to July 2023: Workshops at local sites with the Mayors concerned and associated institutional and technical partners (EPCI, Département, Région SUD, CAUE, UPACA, Syndicat des professionnels...) .

    This pre-operational construction involved comparing the proposals obtained with the site constraints and municipal intentions. Prior to these sequences, the S.M.A.DE.SE.P. worked on putting the collected proposals into graphic form (project sketches).

  • August/September 2023 : Synthesis and costing of proposals by sector (as part of an overall coherent project for the whole lake) .

Emergence of the resilience plan Operational construction combining municipal intentions, uses and technical constraints.

This concerted and coherent public development policy has led to the creation of 77 operations with a projected budget of almost 33 million euros (excluding VAT) . You will find the operational table of these operations below.

However, it is important to retain the top priorities, for which the Chairman has proposed to focus on adapting beaches and public ports to the tidal range, which will be severely impacted by the summer drought in 2022. Below are the priority operations selected (provisional plan):

office de tourisme de serre-ponçon