Severalls Lane Bridge is located on the A12 Colchester Northern Bypass and in March 2020, two of the bridge’s beams were damaged as a result of impact from an excavator being carried on the back of a flatbed lorry driving beneath.

National Highways has stated that it will use an innovative technique to repair the bridge but this cannot be done until 2025-26 due to the amount of disruption expected from closing the A12.

As a result of this bridge strike, the road that is carried by the bridge has been restricted to a single 3m wide lane on top of the beam adjacent to the eastern verge since the incident, almost four years ago. A temporary vehicle restraint system is currently being used to prevent any vehicle moving over the part of the deck that is still supported by the damaged beams.

The impact also caused substantial localised damage to the two western-most beams above the A12 northbound carriageway and the transverse bracing between the beams, with significant deformation of the lower flanges and bracing.

The bracings have also been disconnected from the inner beam where the connecting bolts have sheared. The inner beam appears to have a slight kink in the bottom flange at the point of impact, according to National Highways.

To remediate the damages, National Highways has proposed to heat straighten the two damaged beams, carry out localised concrete repairs to the bridge deck and replace one bearing to the north pier to the bearing shelf.

A spokesperson for National Highways said: “This is an extremely complex repair which we want to carry out without significant closures to the A12 and the inconvenience that would cause to many people.

“We now have an agreed strategy to repair the bridge, and an associated traffic management plan with Essex County Council. This will cause the least amount of disruption to communities and significantly shorten the length of time the bridge will be under repair and unavailable to local people.

“The innovative repair will use heat to straighten the damaged sections. This work requires specialist contractors but will avoid lengthy closures to both the bridge and the A12 that it crosses.

“We are now in the final design phase. Once that is completed, we will look to carry out the repair. This will be in the next 18 months – if not sooner.

“This remains a very challenging repair and we understand the time it is taking can be frustrating, but our approach has always been to avoid the A12 and the bridge itself being closed for a prolonged period of time as this would result in significant levels of traffic being diverted through Colchester.

“The repair work will still require road closures over the bridge and on the A12, but this will be minimal compared to more traditional methods of bridge repair. This will benefit the local community and road users as the works will be completed with minimal disruption.”

The severity of the A12 bridge strike is underlined by the fact that the total costs National Highways is currently estimating it will have to pay out for all other bridge strikes between 2019 and 2022 totals £1.2M for 59 bridge strikes, according to a Freedom of Information request sent by NCE. This works out as an average of £20,339 per bridge strike.

However, the roads operator still has 27 cases to cost from this period.

Bridge strikes are an even bigger concern for Network Rail. This has prompted the rail operator to launch a ‘Wise Up, Size Up’ campaign in an attempt to raise awareness and minimise these incidents.

There were 1,572 bridge strikes reported across the railway network in the UK from April 2022 to March 2023 alone.

A Freedom of Information request submitted by NCE revealed that the rail operator hasn’t yet estimated costs for remediating bridge strikes for the last three financial years.

However, for 2019-20 bridge strikes, Network Rail has calculated remediation costs as £6.4M. Network Rail figures for 2018-19 show that it paid just over £5M to fix bridge strikes.

A large proportion of this money is available to be recovered through third party insurance. For 2019-20, Network Rail was able to recover nearly £4.4M of the £6.4M (69%).

A Network Rail spokesperson said: “Every time a vehicle hits a bridge it can cause serious safety issues for road and rail users. To compound matters, these incidents can delay tens of thousands of passengers while we inspect the bridge and repair any damage – creating cost from public funds which should be used upgrading and improving our network.

“We’ve done a lot of work with transport partners to tackle bridge strikes, and whilst it’s encouraging to see this is paying off there’s a lot more to be done. We urge operators and drivers to properly plan their routes, know the height of their vehicles and be vigilant for road signs showing the height of bridges. Those who don’t risk losing their licences – a measure enforced by the traffic commissioners. Network Rail always looks to recover the repair and delay costs from the driver and the operator.”

Figures provided to NCE through a Freedom of Information request regarding bridge strikes to Network Rail infrastructure can be seen below.

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