Scheme in detail

Scheme in detail

We’re carrying out a number of improvements to improve the flow of traffic, providing a safer and more integrated network for everyone, and bring real benefits to the drivers who use junction 28 daily.

If we don’t improve the junction, it is predicted that:

  • delays will be at least five times greater than they currently are
  • average speeds could be reduced by around 25% through the junction
  • the local air quality will worsen
  • it will constrain development and economic growth in the area
  • more widespread disruption following incidents

Existing junction

(Junction 28 as it is now)

Our improvements include:

  • a new two-lane loop road with hard shoulder, for traffic travelling from the M25 anti-clockwise onto the A12 eastbound (towards Brentwood). This merges into a single lane to provide a smooth transition between the loop road and A12
  • changing the A12 eastbound to allow traffic from the loop road to join into a dedicated lane
  • moving the A12 eastbound exit slip road, for traffic using junction 28; and the M25 anti-clockwise entry slip road, for traffic leaving junction 28, to accommodate the new loop road
  • widening the M25 anti-clockwise carriageway to provide additional space for traffic leaving to join the A12
  • two new road bridges, one carrying the A12 eastbound exit over the loop road, the other to take the loop road over the M25 anti-clockwise entry
  • constructing three attenuation ponds, two within the loop road and one to the west. These ponds help us manage surface water from the roads and reduce the risk of flooding
  • diverting the Weald Brook and Ingrebourne River to allow construction of the new slip roads
  • bridges to take the loop road over the Weald Brook and Ingrebourne River that include specially designed tunnels, known as culverts, which ensure water flows freely under the road, while allowing the movement of wildlife on the banks of the brook
  • the installation of new gantries and signage to help everyone move around the junction safely
  • landscaping, seeding, planting and improvements to enhance and protect the local wildlife. This includes special fences to keep deer, otters and other wildlife off the road

Montage of images of the improvements

(Proposed improvements)