M6 Closure Northbound, Cheshire, Thursday 17 August 2017

The M6 north­bound in Cheshire had three of the four lanes closed between
J20 — J21, and the M6 north­bound was fully closed fur­ther back between
J19 — J20, while we worked hard to make safe a defec­tive bridge
joint on the Thel­wall Viaduct

On the M6 between J20 — J21, the motor­way car­ries traf­fic over the Man­ches­ter Ship Canal and the River Mersey. This part of the M6 is also known as the Thel­wall Viaduct.

At 12:33, our col­leagues in the North West Motor­way Police Group alerted the
High­ways Eng­land motor­way con­trol room that there were reports of debris in the
north­bound car­riage­way which was caus­ing vehi­cles to take eva­sive action. The debris was quickly located on CCTV: warn­ing sig­nals were imme­di­ately acti­vated and a Traf­fic Offi­cer patrol dispatched.

At 12:47, with our Traf­fic Offi­cer patrol now on-scene, the debris was iden­ti­fied as a bridge expan­sion joint, strad­dling sev­eral lanes of the four lane motor­way. The nature of the joint was a large and very heavy metal plate.

Traf­fic was tem­porar­ily halted while an attempt was made to remove the debris, but it was far too large and far too heavy to move safely. Our Traf­fic Offi­cers imme­di­ately radioed for two spe­cial­ist Main­te­nance Response Teams to attend the scene.

To keep delays to a min­i­mum, traf­fic was then allowed to con­tinue onwards at 13:11, but three lanes had to remained closed to pro­tect motorists from strik­ing the debris.

Our spe­cial­ist Main­te­nance Response Teams arrived on-scene at 13:16, but with only one lane open, delays and queu­ing traf­fic had inevitably began to build-up. By this time, there was approx­i­mately 4½ miles of queu­ing traffic.

As delays grew, our National Inci­dent Liai­son Offi­cers based at our National Traf­fic Oper­a­tions Cen­tre near Birm­ing­ham set strate­gic sig­nage at the road­side to warn of the delays, pub­lished a Break­ing News arti­cle on our web­site, engaged with motorists on Twit­ter and issued reports to media out­lets and travel hubs. Our
cus­tomer con­tact cen­tre was also on-hand to answer calls from the public.

As our spe­cial­ist Main­te­nance Response Teams swiftly set to work to clear the debris, it was iden­ti­fied that the prob­lem was far greater than at first realised.

Emer­gency repairs were needed to sev­eral more of the very heavy bridge expan­sion joints and the 12 robust bolts that secured each one safely in place. Fur­ther resources were dis­patched to the scene, includ­ing heavy plant equip­ment equipped with an on-board Hiab lift­ing crane.

By 13:55, the queu­ing traf­fic was gen­er­at­ing a delay of approx­i­mately 2 hours.

At 14:38 it became nec­es­sary to fully close the M6 north­bound fur­ther back, between J19 — J20, to take advan­tage of the strate­gic diver­sion routes in order to pre­vent
traf­fic queues and delays from esca­lat­ing further.

Traf­fic was diverted off the motor­way at J19 and directed to travel north on the A556 towards Altrin­cham, then to join the M56(E) towards Wythen­shawe, then to join the M60 clock­wise and then to join the M62(W), to re-join the M6(N).

Although the dis­tance trav­elled by the diver­sion route was sig­nif­i­cant, it remained a quicker alter­na­tive to stay­ing on the M6.

By 20:35, our engi­neer­ing teams and spe­cial­ist Main­te­nance Response Teams had com­pleted their work. How­ever, time was then needed to allow the tar­mac and sealant glues to cool and set. But by 21:40, we were able to begin remov­ing the
clo­sures so that by 22:42, all lanes were run­ning again.

High­ways Eng­land realises that this inci­dent caused unavoid­able dis­rup­tion and we would like to sin­cerely thank our cus­tomers for their patience and under­stand­ing throughout.