Homeowners turn to flood defence systems with government backing

Interest in flood defence systems for homes has risen following the government’s roll-out of financial aid to protect against extreme weather events.

Doorway flood barriers, called batardeau, are proving especially popular – and are eligible for grants of up to 80% from the state under the so-called Fonds Barnier scheme.

Created in 1995, the fund was set up to protect people and property exposed to major natural hazards. 

It can be used by local authorities, small businesses, individuals, public land institutions, and government departments.

Michelle Jobert, a manager at Isoflots, a flood barrier firm near Carcassonne in Aude, says at least half of the company’s business, which has doubled each year for the past three years, comes from people who were helped by the Fonds Barnier.

“It is not something which is easy to get – there is a lot of paperwork,” Ms Jobert warns.

“People tell us it takes months to get approval, and in some cases years.”

The firm’s barriers are mostly based on a system perfected over the years by home owners and businesses along the Gironde estuary, where high tides and westerly winds frequently cause flooding. 

Rails fitted to the walls and steps in front of doors served as guides for steel plates to slide into, preventing water ingress. 

Rubber or cloth seals between the plates and rails helped to further reduce the risk of flooding.

“Some of our systems still have the rails and joint at the bottom, but the barrier is now made out of aluminium ‘planks’, which are much lighter and easier to manipulate,” says Ms Jobert.

“As long as the seals fitted to the planks and rails are kept lubricated, it is very easy to put up and take down.”

Other systems use levers along the sides and bottom to lock and seal the barrier.

Prices vary, but expect to pay around €4,000 for a garage door system. 

Another company, called FlowStop, offers inflatable barriers made from the same material as blow-up paddle boards.

Award winning innovation

The Connexion first reported on them in 2023, after they won the Concours Lépine inventors fair.

Co-founder Bertrand Sylvestre-Boncheval says: “The system we patented has one bag that fills the space from side to side, and only after that is inflated is a second bag blown up, which seals the space at the bottom.”

Like Isoflots, Flowstop has seen demand for its products, which are priced between €600 for a 90cm door to €1,800 for warehouse doors, rise sharply each year.

More information on Fonds Barnier – officially called the fonds de prévention des risques naturels majeurs (FPRNM) – can be found here.  

For home owners in zones designated as being susceptible to flooding, the point of contact is the local direction départementale des territoires, a body usually attached to the prefecture.

A request will result in a detailed audit of the risk of flooding (unless such a plan has already been carried out by the commune), which the state pays for. 

Only after this will the process move on to consideration of whether a batardeau will reduce the risk. If agreed that it will, the 80% funding can kick in.

Other work that can be funded by the FPRNM includes installation of escape hatches in roofs, moving electricity boards to higher levels, or anchoring reservoirs used for oil-fired central heating systems so they do not float away and cause pollution.