Mise à jour le 8 November 2023

Restoration of the Huisne’s ecological continuity in Le Mans

Actions on watersheds

Background

The Huisne river meets the Sarthe river at the heart of the city of Le Mans. The Huisne river is a water body whose objective is to reach a good ecological status. The crossing of Le Mans city embodies the most urbanized part of the river. One of the restricting factors preventing the river from reaching a good status is the absence of ecological continuity. When going through Le Mans city, the Huisne river meets 4 dams. Those 4 dams layouts constitute an ambitious and global project of restoration of the ecological continuity of the Huisne river. The LIFE project funds the first steps of implementation. The rest of it will be funded by the Loire Bretagne Water Agency and the Pays de la Loire Regional council in the framework of the CT EAU of downstream Huisne.

 

Schedule & Location

1st quarter 2023 / 4th quarter 2027

In Le Mans, on the Huisne water body from the Epau dam to the Pontlieue dam.

Objective

The action aims to restore the ecological continuity on the Huisne while crossing Le Mans.

  • by laying out a fish way to restore the fish continuity around at the Epau dam.
  • by starting the dismantling project of the Pontlieue dam (concertation / information of residents)
  • by communicating about layout projects on the different dams.

Description of the action

This action is broken down into several sections :

1- Creation of a fish way on the Epau dam (2023 – 2025)

After having done a feasibility study and requested an environmental permit, construction will start in 2024. To realize this project, various services will work hand in hand: water services, nature in city service, the Arche de la Nature, the Architecture/technic management service and the Energy-Climate service.

2 – Consultation with the residents of the area on the left riverbank upstream the Pontlieue dam.

After the dam dismantling, further layouts will be necessary to maintain the water level and restore or reinforce the riverbanks. Hence it is necessary to inform and raise awareness among the residents involved to obtain their authorization, which is mandatory to realize the constructions (General Interest Declaration). A prime contractor will be hired to realize this consultation.

3 – Evolutive exhibition describing the whole project on Le Mans dams and its global objective.

An evolutive exhibition on the different actions on the dams will be organized in the Water House, to make people understand the ecological point of those constructions. A consultation will be launched in 2023 to hire a service provider to create this exhibition.

Main results expected

– Fish continuity restored at Epau dam

– Local support for the Pontlieue project and DIG approval obtained

– Creation of an evolving exhibition to help visitors understand the overall project for the 4 Le Mans dams.

All river basin actions
All the actions