Timber bridge in Norway ‘built to last 100 years’ collapses after a decade

Two people had to be rescued this morning during the major incident on Tretten Bridge near Gudbrandsdalen in Øyer.

A car plunged into the water as the bridge fell apart, while a lorry became stuck on a collapsed section. Both drivers escaped unharmed.

Tretten Bridge, which only opened in 2012, runs between Norway's main north-south motorway and county road 254 in Øyer municipality, just north of Lillehammer.

It serves as a crossing point for the 900 inhabitants in the village of Tretten, and was built to replace a previous structure which had been there since 1894.

Constructed of timber and steel, it is almost 150m long and 10m wide and has a two-lane road and a pedestrian walkway.

It was designed by architect PLAN Arkitekter with engineer Norconsult and contractor Contexto. The structure was designed with a life expectancy of 100 years, according to a report prepared by the architect and engineer in 2013.

Tretten bridge crossing Gudbrandsdalslågen collapsed this morning. Hopefully no injuries, as the vehicles seen seem to have gotten away with little or no damage pic.twitter.com/dDyXi3u0h9

— Bernie’s Mittens and the Battery Electronic Car (@torbenbrenden) August 15, 2022

Tretten Bridge was inspected along withother wooden truss bridges in 2016 following the collapse of Perkolo Bridge, another timber crossing in Gudbrandsdalen.

According to a report by Norweigan broadcaster NRK, some maintenace issues were discovered, but nothing that led to it being declared unsafe for traffic.

An investigation has now been launched by the Norwegian Public Roads Administration and Innlandet County Council, which owns and maintains the bridge.

In a statement, Norway's road director Ingrid Dahl Hovalnd said: "We must have a complete and independent review of the incident. It must be safe to drive on Norwegian roads. That is why it is important to get to the bottom of this matter."

The authorities have also decided that all wooden bridges in the region will be re-inspected.

A police statement added: "At 07.34, the police received a report that a bridge in Tretten had collapsed. A truck and a car were affected.

"It is currently unknown how many people have been affected by the accident. The driver of the car has been taken care of by the health service."

Click here for the engineers' early theories as to why the bridge collapsed.

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