A4 road works likely to cause months of traffic congestion in Chiswick

Image above: The bridge over the rail tracks on Great West Road which needs repairing; Photograph Google Streetview

First phase of work begins 5 August

This story has been updated on Monday 8 August 2022

Transport for London is warning we can expect months of significant traffic congestion in Chiswick while roadworks are carried out on Great West Road (A4) near Harvard Hill.

From 5 August until the end of the year, TfL contractors will be carrying out essential maintenance and refurbishment works on the Cromwell Road Railway Bridge over the railway line that runs between Gunnersbury and Kew Gardens. TfL says the work will improve the long-term condition of the bridge, road and pavements.

As the work is carried out there will be series of lane closures in both directions until late December on the A4 between Chiswick Roundabout and Hogarth Roundabout. There will also be some full closures of the road overnight and at weekends.

These will at times also affect the M4 between junction 3 and Chiswick roundabout.

The work is bound to displace traffic onto Chiswick High Rd at the time LB Hounslow is also planning to start work on the next phase of Cycleway 9, putting in bus shelters amongst other changes in the process towards making the cycle lane permanent.

READ ALSO: Next phase of work to C9 to go ahead in September

While the work is going on LB Hounslow has decided to relax the traffic restrictions in Grove Park on the days when two lanes are closed. Effectively this will be from Friday 5 August – Wednesday 12 October and on four Saturdays in November and December.

Between October 12 and the end of December the traffic restrictions will be relaxed on Saturday 26 November, Saturday 3 December, Saturday 10 December and Sarurday 17 December.

READ ALSO: Access to Grove Park during roadworks on A4

Image above: Section of the A4 affected

‘Plan ahead’ says TfL

Phase one of the work begins on 5 August with the full overnight closure of the A4 westbound between Hogarth Roundabout and Chiswick Roundabout. From the following day, just one lane of the A4 westbound will be open on this section until 15 September.

The work involves waterproofing the bridge, replacing the road surface, replacing joints in the bridge and installing new crash barriers.

‘This work will help to ensure that people in the area and beyond can continue to use the bridge and the A4 for decades to come’ say TfL.

‘A series of lane and full closures is needed so that the work can be carried out safely. The schedule of work has been planned carefully to minimise disruption to people in the area, with all full closures of the road taking place overnight or at weekends.

‘Outside of these full closures, at least one lane will be kept open in both directions.  The works have been co-ordinated with other road works in the area to further minimise disruption.’

TfL say car journeys ‘may take longer than usual’ during the works and recommended drivers plan their journeys and take alternative modes of transport.

Check traffic updates here: Status updates

Lane closure details

Phase one

5.00am 6 August – 10.00pm 15 September

  • Eastbound: no closures
  • Westbound: one lane open

Phase two

5.00am 17 September – 10.00pm 12 October

  • Eastbound: two lanes open
  • Westbound: one lane open

Phase three

5.00am 14 October – 10.00pm 25 November


Two 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 three, there will be two weekend full eastbound closures between M4 junction 2 and Hogarth Roundabout. These closures will run from 11.00pm on Friday to 5.00am on Monday on the following dates:

  • Friday 25 November and Monday 28 November
  • Friday 2 December and Monday 5 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 Chiswick Roundabout
  • Westbound between Chiswick Roundabout and Hogarth Roundabout

Closures will run from 10.00pm until 5.00am the next day (except on 16 September).

There will be closures on these dates:

  • 5 August: westbound
  • 15 September: westbound
  • 16 September: westbound closure from 11.00pm
  • 12 October: westbound
  • 13 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 11.00pm Friday 9 December to 5.00am Monday 12 December
  • From 11.00pm Friday 16 December to 5.00am Monday 19 December

Read more stories on The Chiswick Calendar

See also: Main section of Barnes Bridge Walkway installed

See also: Pedestrian walkway opened under arch at Kew Bridge

See all the latest stories: Chiswick Calendar News & Features

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