Great West Road works

Temporary suspension of works

Works on the A4 Great West Road are being lifted until Sunday 25 September.

About the works

Work is needed on Cromwell Road Railway Bridge, which carries the A4 Great West Road over a railway line between Chiswick Roundabout and Hogarth Roundabout. This will improve the long-term condition of the bridge, road, and pavements.

To enable us to carry it out, there will be a series of lane closures and full directional closures on the A4 between Chiswick roundabout and Hogarth roundabout, which will also at times affect the M4 between junction 3 and Chiswick roundabout.

All full directional closures will take place overnight or at weekends. On weekdays, there will be at least 1 lane open for traffic in both directions.

Lane closure details

The works will be completed in 3 phases.

During all phases, access to and from the A4 to local roads may be affected. When required, use the Hogarth roundabout or Chiswick roundabout to join the A4.

To prepare for each phase of work, there will be overnight directional closures, to safely install and remove traffic management. Details on these closures are below.


Phase 2

From 05:00 26 September to 22:00 23 October

  • Eastbound: 2 lanes open (from 05:00 27 September)
  • Westbound: 1 lane open (traffic won't be able to join the A4 from Milnthorpe Road)

Phase 3

From 05:00 25 October to 22:00 2 December


  • 2 lanes open
  • Slip road to join the A4 eastbound at Chiswick roundabout will be closed. Follow the signed diversion route to Hogarth roundabout


  • No closure

Weekend directional closures

Following phase 3, there will be 2 weekend full eastbound closures between M4 junction 2 and Hogarth Roundabout. These closures will run from 23:00 on Friday to 05:00 on Monday on the following dates:

  • Friday 2 December and Monday 5 December
  • Friday 9 December and Monday 12 December

Signed diversion routes will be in place for local traffic.

Overnight directional closures

There will be overnight closures:

  • Eastbound between M4 junction 3 and Hogarth Roundabout 
  • Westbound between Hogarth Roundabout and Chiswick Roundabout

 Closures will run from 22:00 until 05:00 the next day. 

There will be closures on these dates:

  • 25 September wetbound
  • 26 September eastbound
  • 23 October: westbound 
  • 24 October: eastbound  

Signed diversion routes will be in place.

Contingency weekend closures

If needed, there will be full directional closures with signed diversions on these weekends:

  • From 23:00 Friday 16 December to 05:00 Monday 19 December
  • From 23:00 Friday 6 January to 05:00 Monday 9 January


Local journeys

Local journeys may take longer than usual. If possible, consider alternatives, including Tube and rail services, walking and cycling.

Longer journeys

Where possible, use the A40 Westway and M40 to travel between Central London and the M25.

If you have to use this part of the A4 Great West Road, allow more time for your journey and travel at quieter times if possible.


Pavements will be closed on the following dates:

  • 24 November-4 December pavement closed on eastbound carriageway side between Oxford Road North and Harvard Hill

There will be signed diversion routes via the subway at Harvard Hill and tunder the M4 bridge on Wellesley Road. There will be staff around to help people walking at all times.


No buses will be on diversion during these works but some buses may experience local delays, especially at busier times.


Coaches travelling through this area towards the southwest of England may take longer than usual and be delayed, especially at busy times. Routes between central London and Heathrow, the West of England, and South Wales may be affected, Check with your coach operator.

Use our travel tools

Check before you travel and plan ahead using our travel tools. Keep up-to-date with the latest service information.

  • The TfL Go app has interactive maps, live arrival times and other travel information
  • Journey Planner can help you plan your route by public transport, cycling or walking
  • See the latest status updates for roads in the area
  • Nearby, uses your current location or a postcode or address of your choice and places you on a map, showing you Tube, bus, river, rail and Santander Cycles locations around you
  • Check our email updates