The report was commissioned by the French Senate following the collapse of the Morandi motorway viaduct in Genoa, Italy, in August 2018, which killed 43 people.
The report has now called for an urgent “Marshall plan” to be put in place to begin rapid repairs.
Presided over by centrist Eure senator Hervé Maurey, it said: “At least 25,000 bridges are in a poor structural state and present issues of safety and usability for users.”
It added: “Damage to bridges has greatly increased over the past 10 years”, attributing this to aging post-war construction, and “chronic under-investment in heritage maintenance”.
Of the 25,000 bridges identified, 7% are managed by the State, of which 2,800 have been deemed “at the end of their life”. More than 8% of departmentally-managed bridges were judged “problematic”, along with 18-20% of commune and inter-commune crossings.
The viaduct of Gennevilliers (Hauts-de-Seine) had already been identified as requiring urgent attention, following the collapse of a supporting wall in May 2018.
Yet, the report admitted that it was not certain of the exact number of crossings in France. It estimated that there are between 200,000-250,000.
Senators said they were astonished to see “the absence of a comprehensive record of all bridges managed by local and regional authorities”, and said this showed “shortcomings in the [national] monitoring and maintenance policy".
In May 2018, transport minister Elisabeth Borne admitted that France had “bridges that were not all new”.
Now, senators are calling for €120 million to be invested by 2020 - up from the €45 million average invested in recent years - and for the creation of a new €1.3 billion local authority fund over the next 10 years (€130 million each year for 10 years).
The report has recommended that a wider assessment be carried out across all local bridges, and for renovation works to begin urgently on those found to be in a poor state.
Senators have also called for more unified “heritage management of bridges”, including an improved monitoring system for necessary works.
They also said that it would be necessary “for regional areas to offer engineering support to smaller areas”, and supported a plan that would bring together work management at an intercommunal or even departmental-wide level.
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