M4 junctions 3-12: smart motorwayRecently updated

Making the M4 a ‘smart motorway’ between junctions 3 and 12.

Region:  South East
Start date:  2016/17
Cost:  £586.4 to £862.4 million
Status:  CURRENT
Type:  Major Scheme
End date:  2021/22
Programme:  Smart Motorways

Progress report

The M4 junctions 3 to 12 project is the first Smart Motorway scheme to receive planning permission through the Development Consent Order (DCO) process. To find out more about the DCO process, please see information in the 'Background' section below.

The DCO consultation for the M4 junctions 3 to 12 Smart Motorway project took place between 2013 and 2015 with letters sent to over 26,000 addresses along the route and a comprehensive programme of consultation and engagement with local authorities, the local community, road users and key stakeholders.

The Secretary of State made a formal final decision on 2 September 2016 to grant development consent for the scheme. You can find the documents relating to this decision on the Planning Inspectorate website.

Following this decision there was a six week period in which the decision could have been challenged in the High Court. This process of legal challenge is known as Judicial Review. The deadline to challenge in the High Court was 15 October 2016, which has now passed.

View our recent newsletter about the scheme in the 'Media and Documents' section below.

What's next?

We are at an exciting time on the project. Preparation work, which includes further design, archaeological and site surveys, began in 2016 leading to the main construction work which will start in Autumn 2018. We will be holding a number of Public Information Events in July 2018 in advance of the construction work commencing. To find out more about these, please see the 'Community news' section below.

We will need to set up a number of construction compounds along the M4.

During construction, narrow lanes and reduced speed restrictions will be put in place to create a smooth and safe flow of traffic through the works and to protect workers. Additionally, traffic management barriers will be needed. Three narrow lanes will be available for road users during peak hours.

Timeline

Date Event
March 2008 Advanced motorway signalling and traffic management feasibility study identified this motorway link as a priority for additional capacity
2009 Department for Transport announces a programme of smart motorways, including this scheme
2010 Scheme development commenced
2013 Roads Minister announces funding for this scheme
November 2014 to December 2015 Pre-application consultation
January to February 2015 Speed limit consultation
30 March 2015 Development Consent Order submitted
27 April 2015 Planning application accepted for examination
July 2015 CH2M and Arcadis appointed to develop detailed scheme design
July 2015 Balfour Beatty Vinci Joint Venture appointed to develop construction methodology and programme
2 September 2016 Secretary of State decision
15 October 2016 High Court Challenge period ended
March 2017 Start of preparation works
July 2018 Public information exhibitions
Autumn 2018 Start of main works
Spring 2022 Smart Motorway complete and operating

News

Traffic management installation between junctions 8/9 to 10 during night closures

If you attended one of the recent public information exhibitions (view a summary leaflet from the events) or have seen the project in the local news you will be aware that main construction works start between junctions 8/9 and 12 in September 2018, with preparatory activity taking place over the summer. The first works you will see on the motorway itself will be the installation of traffic management on sections of the M4 between junctions 8/9 to 10. This will involve closures of the motorway overnight between junctions 8/9 to 10 and more details on specific dates* can be found below:

  • Saturday 18 August 2018 - Eastbound
  • Sunday 19 August 2018 - Eastbound and Westbound
  • Monday 20 August 2018 - Westbound
*In the event of poor weather conditions or other issues out of our control, works may be postponed at short notice. If works complete ahead of schedule the motorway may reopen early. Please check the Roadworks section below for more details on roadworks.

The traffic management installed will comprise of three narrowed lanes, a 50 mph speed restriction, removal of the hard shoulder and new signage in the area. Traffic will be diverted overnight via the A3290, A329M, A4 and A404M. Mobile Variable Message Signs (VMS) will be used to display information at different locations in and around the motorway to provide prior warning of works.

Construction of project compounds

We are setting up several construction compounds along the M4 for storing materials, equipment, vehicles and to provide welfare facilities for our workforce. Our main construction compound and site office will be located at a purpose-built site east of junction 10, on the north side of the motorway close to the A321. Heavy Goods Vehicles (HGVs) will only be able to access and exit the main compound from new dedicated slip roads directly onto the eastbound carriageway. Once complete, our main compound will also provide rescue and recovery facilities to assist users of the M4. Meanwhile, we will use existing local facilities in the interim to help motorists in difficulty. We will also have smaller compounds on land within junction 10 itself, and adjacent to junction 12.

A new video about the M4 junctions 3 to 12 upgrade to smart motorway is now available to view in the 'Media and Documents' section below.

Indicative timing of the works

This is the longest smart motorway project in England to date (51km, 32 miles). To minimise disruption to our customers we will need to work on different stages at different times.

Our current intention for the phasing of construction, is to start at junction 8/9 and progress west towards junction 10. In tandem we will start work on four bridges between junction 8/9 and junction 7. The more complex section of the scheme, progressing east from junction 8/9 towards junction 3, will be started in May 2019.

The table below indicates which sections of motorway we expect to be working on at any given time.

Timetable subject to governance, funding approval and discharge of the DCO.

Link Start End
Junction 12 to 11 May 2020 February 2022
Junction 11 to 10 May 2020 January 2022
Junction 10 to 8/9 September 2018 May 2020
Junction 8/9 to 6 May 2019* December 2021
Junction 6 to 5 December 2019 March 2022
Junction 5 to 4b October 2019 March 2022
Junction 4b to 3 January 2020 March 2022

* Mobilisation work to 4 structures in junction 8/9 to 7 link will also start in late autumn 2018

Bridge works

Much of the M4 was originally built as a two-lane dual carriageway, and has been upgraded over the years. Eleven bridges over the motorway need to be replaced to make room for a new lane where there is no existing hard shoulder.

To limit local disruption, new bridges will be built next to the existing ones, before the old one is demolished. However, where there is not enough space for this, some bridges will be demolished first, then a new bridge built in the same place.

Where the motorway passes over, for example, the River Thames at Bray and the railway line to Windsor, we will need to widen structures to support the new smart motorway.

Considerate construction

Wherever possible, noisier works will be undertaken during daytime hours to reduce disturbance.

There will be temporary closures of the carriageway and slip roads at night on some occasions. In these instances, the closure will be advertised, and advance warning signs and clearly signed diversions will be put in place. You can use the Roadworks section below to find information about roadworks as the scheme progresses.

The construction of the scheme will be governed by the Construction, Design and Management Regulations, and we will be a member of the Considerate Constructors scheme which will help ensure that we are a good and responsible neighbour.

Further details will be provided on these project web pages as they become available both before and during construction. Please sign up for updates using the link on the right if you would like to receive notifications when the web page is updated.

Why we need this scheme

The M4 is the main strategic route between London, the West of England and Wales. It connects people, communities and businesses, carrying on average 130,000 vehicles per day and is prone to congestion.

Highways England will be improving the M4 between junction 3 at Hayes and junction 12 at Theale by upgrading it to a smart motorway which will provide much needed capacity and support the economy and facilitate economic growth within the region. This means there will be:

  • an additional lane for traffic increasing capacity to reduce congestion
  • more technology on the road to smooth flows and manage incidents
  • more reliable journeys

The scheme in detail

This scheme will use the latest technology to improve journeys by monitoring traffic flow and setting speed limits accordingly. This helps to keep traffic moving smoothly, instead of continually stopping and starting.

Information about road conditions and speed limits will be displayed to drivers on electronic road signs.

The proposal also involves converting the hard shoulder permanently to a traffic lane. This will create much needed extra capacity necessary to support economic growth.

Key changes to the motorway

All Lane Running: between junctions 3 and 12 the hard shoulder will be converted to a traffic lane, so that there are four lanes available for use by road users. Between junctions 4 and 4b, there will be five lanes. Where a hard shoulder does not currently exist, the motorway will be adapted to create a minimum of four lanes. The barrier in the central reservation will be replaced by a new concrete barrier.

Through junction running: This enables a consistent number of lanes to pass through the junction, reducing the need to change lane for vehicles staying on the motorway. Through-junction running will be in place at junctions 4, 5, 6, 7, 8/9 and 11 and at the Reading motorway service area.

Bridge works: To accommodate the new smart motorway:

  • 11 bridges carrying local traffic over the motorway will need demolition and replacement
  • 4 bridges that carry the motorway over roads, railways and rivers will need widening
  • 2 subways under the motorway will also need lengthening

Emergency areas (EAs): there will be new high visibility Emergency Areas between junctions 3 and 12. Places of relative safety will be every 1.12 miles on average and no more than 1.6 miles apart. If you are driving at 60mph you will pass one approximately once a minute.

Aims

The objectives of the proposed scheme are to:
  • reduce congestion
  • smooth the flow of traffic to improve journey times
  • make journeys more reliable
  • support the economy and facilitate economic growth within the region, by providing much needed capacity on the motorway
  • continue to deliver a high level of safety performance on the network using smart motorway techniques and minimise environmental impacts of the scheme

Development Consent Order

The DCO process was established by the Planning Act 2008 and is used for certain large and complex schemes (including highway improvements) that have been designated as a Nationally Significant Infrastructure Project (NSIP) by the Government.

The benefits of the DCO process include extensive pre-application consultation, detailed analysis, including a full Environmental Impact Assessment, and examination by an independent inspector before the final decision is made.

Development Consent Order – requirements register

We made a commitment to publish and update a register listing the requirements to be completed as part of the Development Consent Order (specified under the Register of Requirements in Schedule 2). This sets out:

  • each requirement
  • whether the requirement needs approval by the Secretary of State (or other duty holder)
  • whether any approval has been applied for or given

Environmental impact

As part of the DCO planning process, a full Environmental Impact Assessment was carried out and has been used to inform the design of the project. This included assessments and design of mitigation where needed for:

  • air quality
  • cultural heritage
  • landscape
  • ecology and nature conservation
  • geology and soils
  • materials
  • noise and vibration
  • effects on all travellers
  • community and private assets
  • road drainage and the water environment

During the examination of the application, further environmental protections were requested and planning requirements attached to the consent.

Project media files and documents

Project timeline

Planned roadworks

Roadworks and Events for England

The latest incident information for England's motorway and trunk routes provided by Highways England

Location : The A404M southbound between junctions J9B and J9A . Lane Closures : The hard shoulder is closed. Reason : Emergency roadworks. Status : Currently Active. Period : expect disruption until 17:00 on 16 August 2018.
Posted: August 16, 2018, 8:01 am
Location : The M4 eastbound between junctions J10 and J8 . Reason : Roadworks scheme. Status : Currently Active. Period : from 21:30 on 13 August 2018 to 07:00 on 1 September 2018.
Posted: August 16, 2018, 6:35 am
Location : The M3 westbound between junctions J3 and J4 . Lane Closures : Lanes 2, 3 and 4 are closed. Reason : Roadworks. Status : Currently Active. Period : expect disruption until 06:00 on 17 August 2018. Lanes Closed : There are three of four lanes closed.
Posted: August 16, 2018, 6:04 am
Location : The M4 westbound between junctions J8 and J10 . Lane Closures : The hard shoulder, lanes 1 and 2 are closed. Reason : Roadworks. Status : Currently Active. Period : expect disruption until 06:00 on 17 August 2018. Lanes Closed : There are two of three lanes closed.
Posted: August 16, 2018, 5:53 am
Location : The M3 westbound between junctions J2 and J3 . Lane Closures : Lanes 2, 3 and 4 will be closed. Reason : Roadworks are planned. Status : Pending. Schedule : From 22:00 on 16 August 2018 to 06:00 on 17 August 2018. Lanes Closed : There will be three of four lanes closed.
Posted: August 16, 2018, 5:02 am
Location : The M3 westbound at junction J3 . Lane Closures : Lanes 2 and 3 will be closed. Reason : Roadworks are planned. Status : Pending. Schedule : From 22:00 on 16 August 2018 to 06:00 on 17 August 2018. Lanes Closed : There will be two of three lanes closed.
Posted: August 16, 2018, 5:02 am
Location : The M3 eastbound at junction J3 . Lane Closures : Lanes 1, 2 and 3 will be closed. Reason : Roadworks are planned. Status : Pending. Schedule : From 22:00 on 16 August 2018 to 06:00 on 17 August 2018. Lanes Closed : All lanes will be closed.
Posted: August 16, 2018, 5:02 am
Location : The M3 eastbound between junctions J4 and J3 . Lane Closures : Lanes 1, 2 and 3 will be closed. Reason : Roadworks are planned. Status : Pending. Schedule : From 22:00 on 16 August 2018 to 06:00 on 17 August 2018. Lanes Closed : There will be three of four lanes closed.
Posted: August 16, 2018, 5:02 am
Location : The M4 westbound between junctions J5 and J6 . Lane Closures : Lanes 1 and 2 will be closed. Reason : Roadworks are planned. Status : Pending. Schedule : Expect disruption everyday between 22:00 and 06:00 from 16 August 2018 to 18 August 2018. Schedule : Expect disruption everyday between 22:00 and 06:00 from 20 August 2018 to 22 August 2018. Lanes Closed : There will be two of three lanes closed.
Posted: August 16, 2018, 5:02 am
Location : The M4 eastbound between junctions J6 and J5 . Lane Closures : The hard shoulder, lanes 1 and 2 are closed. Reason : Roadworks. Status : Currently Active. Period : expect disruption until 06:00 on 17 August 2018. Lanes Closed : There are two of three lanes closed.
Posted: August 16, 2018, 5:00 am
Location : The M4 eastbound between junctions J10 and J8 . Lane Closures : Lanes 1 and 2 will be closed. Reason : Roadworks are planned. Status : Pending. Schedule : From 20:00 on 16 August 2018 to 05:30 on 17 August 2018. Schedule : From 20:00 on 17 August 2018 to 07:00 on 18 August 2018. Schedule : Expect disruption everyday between 20:00 and 05:30 from 22 August 2018 to 24 August 2018. Schedule : Expect disruption everyday between 20:00 and 05:30 from 28 August 2018 to 31 August 2018. Lanes Closed : There will be two of three lanes closed.
Posted: August 16, 2018, 4:31 am
Location : The M4 eastbound entry slip at junction J10 . Lane Closures : Lanes 1 and 2 will be closed. Reason : Roadworks are planned. Status : Pending. Schedule : From 21:00 on 15 August 2018 to 06:00 on 16 August 2018. Schedule : Expect disruption everyday between 21:00 and 06:00 from 21 August 2018 to 24 August 2018. Schedule : Expect disruption everyday between 21:00 and 06:00 from 29 August 2018 to 1 September 2018. Schedule : Expect disruption everyday between 21:00 and 06:00 from 3 September 2018 to 8 September 2018. Lanes Closed : All lanes will be closed.
Posted: August 16, 2018, 1:35 am
Location : The M3 westbound between junctions J2 and J3 . Lane Closures : Lanes 1 and 2 will be closed. Reason : Litter clearance is planned. Status : Pending. Schedule : From 22:00 on 22 August 2018 to 05:00 on 23 August 2018. Lanes Closed : There will be two of four lanes closed.
Posted: August 15, 2018, 9:10 pm
Location : The M3 westbound between junctions J2 and J4 . Reason : Roadworks scheme. Status : Currently Active. Period : from 22:01 on 15 August 2018 to 06:00 on 17 August 2018.
Posted: August 15, 2018, 9:02 pm
Location : The M4 westbound between junctions J7 and J10 . Lane Closures : Lanes 1 and 2 will be closed. Reason : Roadworks are planned. Status : Pending. Schedule : Expect disruption everyday between 20:00 and 05:30 from 16 August 2018 to 18 August 2018. Schedule : Expect disruption everyday between 20:00 and 05:30 from 20 August 2018 to 24 August 2018. Lanes Closed : There will be two of three lanes closed.
Posted: August 15, 2018, 5:30 pm
Location : The M4 eastbound between junctions J10 and J8 . Lane Closures : Lanes 1, 2 and 3 will be closed. Reason : Roadworks are planned. Status : Pending. Schedule : Expect disruption everyday between 21:00 and 06:00 from 18 August 2018 to 20 August 2018. Lanes Closed : All lanes will be closed.
Posted: August 15, 2018, 4:24 pm
Location : The M4 westbound between junctions J8 and J10 . Lane Closures : Lanes 1, 2 and 3 will be closed. Reason : Roadworks are planned. Status : Pending. Schedule : Expect disruption everyday between 21:00 and 06:00 from 19 August 2018 to 21 August 2018. Lanes Closed : All lanes will be closed.
Posted: August 15, 2018, 4:22 pm
Location : The M4 westbound entry slip at junction J10 . Lane Closures : Lane one will be closed. Reason : Roadworks are planned. Status : Pending. Schedule : Expect disruption everyday between 21:00 and 06:00 from 20 August 2018 to 24 August 2018. Schedule : Expect disruption everyday between 21:00 and 06:00 from 28 August 2018 to 1 September 2018. Schedule : Expect disruption everyday between 21:00 and 06:00 from 3 September 2018 to 8 September 2018. Schedule : Expect disruption everyday between 21:00 and 06:00 from 10 September 2018 to 15 September 2018. Lanes Closed : All lanes will be closed.
Posted: August 15, 2018, 4:00 pm
Location : The M4 eastbound between junctions J7 and J6 . Lane Closures : Lanes 1 and 2 will be closed. Reason : Roadworks are planned. Status : Pending. Schedule : Expect disruption everyday between 22:00 and 06:00 from 20 August 2018 to 24 August 2018. Schedule : Expect disruption everyday between 22:00 and 06:00 from 28 August 2018 to 1 September 2018. Schedule : Expect disruption everyday between 22:00 and 06:00 from 3 September 2018 to 8 September 2018. Lanes Closed : There will be two of three lanes closed.
Posted: August 13, 2018, 9:11 pm
Location : The M4 eastbound exit slip at junction J10 . Lane Closures : Lanes 1 and 2 will be closed. Reason : Roadworks are planned. Status : Pending. Schedule : Expect disruption everyday between 21:00 and 06:00 from 20 August 2018 to 24 August 2018. Lanes Closed : All lanes will be closed.
Posted: August 13, 2018, 9:04 pm
Location : The A329M eastbound. Reason : Roadworks are planned. Status : Pending. Schedule : Expect disruption everyday between 21:00 and 06:00 from 20 August 2018 to 24 August 2018. Lanes Closed : All lanes will be closed.
Posted: August 13, 2018, 9:04 pm
Location : The M4 eastbound between junctions J10 and J8 . Lane Closures : Lanes 2 and 3 will be closed. Reason : Roadworks are planned. Status : Pending. Schedule : From 21:00 on 19 August 2018 to 05:30 on 20 August 2018. Schedule : Expect disruption everyday between 20:00 and 05:30 from 20 August 2018 to 22 August 2018. Lanes Closed : There will be two of three lanes closed.
Posted: August 13, 2018, 9:04 pm
Location : The A329M eastbound. Reason : Roadworks are planned. Status : Pending. Schedule : Expect disruption everyday between 21:00 and 06:00 from 20 August 2018 to 24 August 2018. Lanes Closed : All lanes will be closed.
Posted: August 13, 2018, 9:04 pm
Location : The M4 eastbound entry slip at junction J10 . Lane Closures : Lane one will be closed. Reason : Roadworks are planned. Status : Pending. Schedule : Expect disruption everyday between 21:00 and 06:00 from 20 August 2018 to 24 August 2018. Schedule : Expect disruption everyday between 21:00 and 06:00 from 27 August 2018 to 30 August 2018. Lanes Closed : All lanes will be closed.
Posted: August 13, 2018, 9:04 pm
Location : The M3 westbound between junctions J2 and J3 . Lane Closures : Lanes 1, 2 and 3 will be closed. Reason : Roadworks are planned. Status : Pending. Schedule : From 22:00 on 17 August 2018 to 06:00 on 18 August 2018. Lanes Closed : There will be three of four lanes closed.
Posted: August 13, 2018, 9:04 pm

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