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What happens during a motorway closure?

someone driving car

It is often difficult for people caught up in traffic jams on the motorway or a dual-carriageway to understand why the road has to be closed for what can seem like a long time.

Motorway and dual-carriageway closures are very complex and the duration of a closure varies depending on the incident and which emergency service or organisation, for example Highways England has taken the lead at the scene.

Chief Inspector Jason Shears says:

“We understand the frustration that drivers will feel when they’re stuck on a road following a full carriageway closure and we appreciate drivers’ patience and understanding in these incidents. Decisions to close a motorway way or dual-carriageway are never taken lightly.

“We have been working really hard with our partner agencies, which include Highways England and other emergency services, to make sure we are working together in the most efficient way. Our newly updated protocol is one of many examples of how we are working together as ‘one team’. It plays an important part in managing and clearing the carriageways after major or minor incidents.”

Frequently Asked Questions

Why does a motorway or dual-carriageway close?

There are a range of reasons why a motorway or dual carriageway closure may need to be put in place. In the first instance emergency services and Highways England need to establish quickly what is going on so that the appropriate lead agency can take control of the scene to get things cleared and moving as quickly as possible. Some examples of r why a motorway or dual-carriageway may close is a road traffic collision, fire, chemical spillage, damage to barriers or the road.

Do Police always lead on these kinds of incidents?

People think we lead in all instances where a road closure has been implemented however that is not the case. More often than not Highways England will lead on each road closure operation in the first instance as they have the final decision on whether a motorway or carriageway is ready to be re-opened.

Police lead operations where a major incident has been declared or fatalities have occurred, in instances where a road traffic collision has taken place, the scene of a crash will become a possible crime scene where our investigators must gather as much information as possible to establish what happened and whether any criminal charges need to be brought.

Why does it take so long for a motorway or dual-carriageway to re-open following a full closure?

We work hard to minimise disruption on the road network but as the timeline below shows, it’s important for us and the families of those injured to understand exactly what happened. Where a fatality (or multiple fatalities) have occurred, a road closure could be in place for many hours or even days. Our investigating teams must be thorough and need to gather as much evidence as possible before clearing the scene.

Where multiple fatalities have happened it can take a long time to recover the remains of the deceased, if someone has left the vehicle or the impact of the collision was severe, the recovery process is a lot more complicated.

What are emergency services and Highways England doing to make the process of reopening a road easier?

We work closely with Highways England, Avon Fire and Rescue Service, Devon and Somerset Fire and Rescue, and South Western Ambulance service to maintain safety and keep strategic road networks safe – in our force area these include the M4, M5, M48, M32, and M49.

During holiday periods traffic volumes rise on the South West’s roads and can lead to an increase in incidents, particularly along the major M4 and M5 routes. Ahead of the May Bank Holiday weekend emergency services and Highways England met to update our motorway and dual- carriageway closure protocol – ensuring the most efficient and practical handling of major motorway or dual-carriageway closures.

We have listed examples below of incidents that have taken place where road closures were implemented. These timelines will give you an idea of just how many steps need to be taken and which agency took the lead.

man driving car

Case study 1

Between Junction 14 and 15 of the M5 (Northbound) a van went through the central reservation, colliding with two cars. There are four fatalities and due to the severity of the crash a major incident has been declared, with police leading the resolution of the scene.


Day 1

  • 14:36 – Numerous calls received in Police Control Room about an incident on the M5. Some are differing; some reporting the incident is on the Northbound carriageway, some on the Southbound.
  • 14:38 – Roads Policing Units are dispatched to scene immediately
  • 14:39 – Further calls received stating that all lanes are blocked, people are trapped in their cars and fuel is leaking onto the carriageway
  • 1440 – Ambulance and Fire Control Rooms notified, and confirm they’re sending units to attend the scene
  • 14:41 – First calls received reporting possible fatalities at the scene
  • 14:45 – Assistance requested from Gloucester Police to close the Southbound carriageway
  • 14:46 – Force Duty officer and Roads Policing Inspector notified of incident
  • 14:47 – Four fatalities confirmed at scene
  • 14:48 – ‘Major Incident’ declared due to the number of deaths and subsequent impact on the motorway and surrounding areas
  • 14:49 – Police helicopter requested to assist in search of surrounding area to ensure no vehicles or injured parties have left the carriageway
  • 14:55 – Multi-agency meeting set up at Police Headquarters led by the Force Duty Officer
  • 15:00 – Specialist Collision Investigation officers attend the scene
  • 15:10 – On call Duty Superintendent notified
  • 15:22 – Press Officer and the on Duty Gold Commander notified
  • 15:26 – Road Policing Senior Investigating officer attend the scene
  • 15:49 – First Ambulance leaves the scene with an injured party
  • 15:58 – Portable screens requested to shield scene from public
  • 16:14 – Traffic now building up for three to four miles
  • 16:22 – Northbound traffic diverted onto the M4, with stationary traffic turned round and taken back off slip road
  • 17:33 – Vehicle Recovery units arrive at the scene to assess recovery of the vehicles involved
  • 17:52 – Lighting equipment arrives to illuminate the scene for forensics
  • 18:17 – Fire and Ambulance units complete their roles at the scene
  • 18:32 – Lane 3 of the M5 (Northbound) reopened to assist in clearing stationary traffic. Lanes 2 and 3 remain closed until all those who are deceased are recovered
  • 18:50 – Crime Scene Investigation (CSI) team arrive at the scene
  • 19:10 – Highways England Inspector arrives at the scene to assess damage to the barriers and comes to the conclusion repairs are needed
  • 20:23 – Southbound traffic backlog finally cleared but remains closed so that repairs to the barriers can be made (significant damage was made to the central reservation of the M5)

Day 2

  • 04:11 – Central barrier replaced
  • 05:52 – Southbound carriageway fully reopened
  • 10:37 – All vehicles involved removed from the scene for examination
  • 10:41 – Specialist officers attend the scene to assist in the recovery of the deceased
  • 19:39 – Lanes 2 and 3 Northbound reopened

Day 3

  • 15:33 – Recovery of deceased complete, motorway fully re-opened

Cars in traffic

Case study 2

Two lorries collide near Junction 21 of the M5 (Northbound) fuel is leaking from one of the vehicles, Highways England take the lead on this operation.


Day 1

  • 06:32 – Report received of two lorries having crashed on the Northbound carriageway of the M5 near Junction 21 (Weston-super- Mare)
  • 06:33 – Highways England notified as the ‘owners’ of the motorway
  • 06:34 – Reports confirm that no one was injured or trapped in the crash
  • 06:36 – First Traffic unit dispatched to the scene
  • 06:39 – Notification received that there had been a spillage of diesel
  • 06:44 – Highways England unit dispatched to assess the damage caused and establish whether diversions need to be considered
  • 06:48 – Local Police unit assist fire and Highways England by stopping more cars joining the M5 at Junction 21, to minimise further congestion
  • 06:51 – Ambulance are at the scene, they also report a fuel leak – around 300 litres of diesel is pouring out onto Lane 1 and the Hard Shoulder
  • 06:59 – Lanes 2 and 3 reopened
  • 08:19 – Even with two lanes open, the tailback is now going back to Sedgemoor Services
  • 08:41 – Rain threatening to wash the diesel into Lane 2 and 3 – Highways England consider fully closing this section of the motorway
  • 11:06 – Highways England confirm that 200-300m of the tarmac across all 3 lanes and the hard shoulder needs to be replaced following damage from the diesel. To minimise the disruption, Lanes 2 and 3 will remain open while Lane 1 and the Hard Shoulder are re-surfaced. Once this has been done, the Hard Shoulder and Lane 1 will be reopened, and Lanes 2 and 3 will be closed for resurfacing. During this time, the Northbound slip road will need to remain closed.
  • 14:08 – Congestion caused by partial closure this is having a knock on effect on all surrounding roads across North Somerset, with A303 and A358 at a crawling pace.
  • 14:35 – Delays of up to three hours being experienced on the M5. Highways England leading with media and communications updates to the public
  • 15:44 – Delays of up to three hours being experienced on the M5. Highways England continue to lead on media and communications updates for the public
  • 19:52 – Resurfacing of Hard Shoulder and Lane 1 completed, but awaiting tarmac to cool sufficiently to re-open to vehicles.
  • 20:50 – Northbound slip road reopened
  • 20:55 – All lanes reopened, with reduced speed limit of 30mph due to resurfacing not being fully cooled. Still 15 miles of tailbacks

Day 2

  • 02:12 – Lanes 2 and 3 closed  because of resurfacing
  • 05:20 – White lines are repainted
  • 0626 – All lanes are now reopened and running normally

Traffic in car mirror

Case study 3

Reports of a lorry on fire on the Hard Shoulder of the M5 Northbound just after Junction 19, Fire take the lead on this operation and Highways England lead on the road closure.


Day 1

  • 08:56 – Numerous reports of a lorry on fire on the Hard Shoulder of the M5 Northbound, just after Junction 19
  • 08:57 – Police notify local Fire Brigade, who are already aware and on route
  • 09:00 – Police liaise with Highways England who are already aware and attending the scene
  • 09:05 – Fire request the closure of Lanes 1 and 2 as the cab of the lorry is now well alight. ‘50’ speed limit advised
  • 09:13 – Highways England tweet on social media about possible disruption and delays to drivers
  • 09:16 – Slip road on to motorway from Junction 19 closed
  • 09:22– Fire reporting cab fire has successfully been put out
  • 09:27 – Highways England assess likely damage suffered to the carriageway
  • 09:30 – Recovery company contacted regarding recovery of cab and trailer
  • 10:03 – Fire recalled to scene as battery from damaged lorry ‘arcing’, giving rise to fears the fire will re-ignited. Fire arrive and disconnect the battery
  • 11:23 – Total carriageway closure put in place to allow Highways England to clear debris off all lanes and hard shoulder
  • 11:51 – Confirmation that 8.5m of hard shoulder and Lane 1 will need to be resurfaced, to a depth of 40mm
  • 14:30 – Damaged lorry is recovered

Day 2

  • 01:33 – Hard shoulder and Lane 1 and 2 closed to allow re-surfacing to be carried out
  • 06:01 – Repairs complete, motorway fully reopened

What can I do to help keep myself safe?

There are a range of practical things drivers can do to reduce the chances of being involved in a road collision or causing a carriageway or motorway closure. Ahead of the summer getaway we are asking drivers to following our vehicle checks and safety advice created in partnership with Highways England.

Car tyre

Be prepared follow our vehicle safety steps:

  • Check tyres: Prior to setting off on a long or significant journey, check your tyre pressure and the condition of your tyres, including the spare. Look out for cuts or wear and make sure the tyres have a minimum tread depth of 1.6mm, which is the legal limit.
  • Check engine oil: Use your dipstick to check  your vehicle’s oil levels before any long journey, and top up if needed. Take your car back to the garage if you’re topping up more than usual.
  • Check water: To ensure you have good visibility, always keep your screen wash topped up so you can clear debris or dirt off your windscreen.
  • Check lights: If your indicators, hazard lights, headlights, fog lights, reverse lights or brake lights are not functioning properly, you are putting yourself and your family at risk. Minor vehicle faults  can be a reason for your vehicle to fail its MoT.
  • Check fuel: Before setting off, check your vehicle’s fuel levels and make sure you have enough to get to your destination.

Reading a map

Check your vehicle there are few other things you can do to help you stay safe on the roads:

  • Plan your journey: work out your route and take any alternative routes or leave earlier to avoid congestion (take a road atlas in case you find yourself without GPS or smartphone signal).
  • Take extra supplies: so you are prepared, for example food, water, blankets, torch.
  • It is illegal to hold a phone or sat nav while driving: you must have hands-free access, such as a Bluetooth headset or a dashboard holder or mat.
  • Travel as light as possible: do not exceed the recommended carrying capacity of your vehicle and be sure that your luggage does not restrict your visibility.
  • Take regular breaks: to avoid getting too tired we recommend once every two hours.
  • Ensure that passengers are occupied: especially children so that the driver can focus on the road.