The closures are needed because the joints along the bridges are leaking water, the
safety barriers appear to be substandard, and there is no kerb drainage or gully
installed over the deck causing water to build up along the verges which is damaging
the substructure. Dealing with these issues now ensures the roads (the roundabout
and the M4 below) will be safer for all users as we head into the winter weather.
Phase one of these works is complete with phase two beginning on Monday 6
January 2025.

Phase 2 – starts 6 January until 16 March. East side of the junction from Reading/Calcot towards A4/Theale.

The second phase of the works on the M4 junction 12 roundabout will affect traffic coming from Reading/Calcot towards the A4/Theale/Newbury (the east bridge and southbound traffic), where essential structural maintenance needs to be carried out by National Highways.

Daytime: The roundabout will remain open and accessible but with lane closures.
Please make sure you follow the signs and use the correct lanes.
Overnight: The east side of the roundabout will be closed with no access.

Key details:
• Route closures towards the A4/Theale/Newbury: The recommended diversion route for vehicles, including HGVs, is via Reading, Basingstoke, Tadley, Aldermaston, and then up to Theale (A4, A4155, A33, A339, A340, A4). Other routes are available but might not be suitable for all vehicles. Please plan your journey in advance, ensuring routes are suitable for your vehicle’s height and weight.

• Lane closures: There will be daytime lane closures over the east bridge during the day. Lanes will be reduced from 3 lanes to 2. Please make sure you follow the signs and use the correct lanes for your journey.

• Overnight closures: East side of the roundabout, including the eastbound exit slip road to the M4 (towards central reading/London) will be closed overnight from 9:00pm – 6:00am, from Monday 6 January to Friday 7 February 2025.

• Weekend closure: East side of the roundabout including the eastbound exit slip road to the M4 (towards central reading/London) will be closed from 9:00pm on Friday 7 February to 6:00am on Monday 10 February 2025.

• Additional overnight closures: 9:00pm – 6:00am, Monday 10 February to Sunday 16 March 2025.

• Contingency weekend closure: Please note an additional weekend closure may be required if the works mentioned above cannot be completed due to weather or other reasons. We will provide dates for this should it be required.

The above restrictions will only be implemented as and when required, dates and times of the closures with their diversion routes will be advertised on site.

All enquiries should be directed to:
• National Highways on 0300 123 5000.