A Gigantic Safety Project for the Rainier III Tunnel Planned for 2020 to 2026

Do you remember that twenty years ago, a refrigerated lorry burst into flames in the middle of the Mont-Blanc tunnel. Thirty nine people were killed leading to a major European overhaul of safety standards – which means that the Rainier III tunnel (completed in 1994) needs to be upgraded with a pedestrian escape route in case of emergency. Cross fingers the escape route will never have to be used.

Fortuitously, due to insightful planning, the Albert II tunnel completed in 2016 included a connection with the Rainier III tunnel. This will allow French firefighters to race to any accident in the tunnel, (or even in the future pedestrian gallery), without having to fight their way upstream back into the Rainier III tunnel.

The escape route for pedestrians via the planned new evacuation tunnel will be 1,100 metres – including eleven shelters for people blocked in case of disaster. That is by itself a gigantic project. And it is the Principality who is the operator of the Rainier III tunnel which in total covers 1,560 metres. Approximately 350 metres are in Monaco and the rest is in France. Monaco’s share of the cost to fund the drilling and development of the pedestrian gallery on the rock is around 60 million euros!

Monegasque Public Works are currently very busy completing feasibility studies because early in 2020 they will need to choose a company to do the construction. That is why the Rainier III tunnel has been regularly closed at night lately. A geological investigation has been continuing which involves “core” drilling at depths of 20 to 50 metres – to determine the nature of the soil and the strength of the rock wall.

The million dollar question, of course, is what this is going to do to traffic flows for the six years between 2020 and 2026 when the pedestrian evacuation route is due to be completed.

And particularly, what about the final three and a half years when the construction will be in full swing. Expect the first two years and a bit to be planning and pre-work paving the way for the final construction phase.

A lot of planning work has been put into minimizing the potential disruption to traffic flows including ruling out the option to have the pedestrian route within the existing tunnel space. A parallel route has been chosen instead. A tunnel boring machine has apparently been ruled out as not cost-effective so explosive charges are going to have to be used to break the rock. Surveying is currently going on which means small controlled explosions with reverberations occasionally felt in the station.

Eventually, the emergency evacuation will pass about thirty metres above the railway and over fifty metres will separate it from nearby urban conglomerations including L’Engelin.

No gain unfortunately without some pain probably to the up to 16.000 vehicles each day that use the Rainier III tunnel. One imagines closure of the tunnel sometimes at night and for parts of the day and also some lane restrictions perhaps – we will have to wait and see how the planners manage to minimize the traffic disruption. Roll on 2026!