M5 J12

M5 Junction 12 is a junction south of Gloucester.

History

1991 plan for north facing slips

The junction was originally built with limited access allowing movements only between the M5 South and Gloucester. This meant traffic in the south of Gloucester wanting to travel north had to drive for several miles through the city to reach Junction 11. It became clear that this was adding to congestion in the city and as early as 1991 there were plans to add north facing slips to J12. Proposals at the time retained the existing freeflow movements to the south. This was never built and the junction remained as it was for another decade.

The old entry slip road during reconstruction

Towards the end of the 1990s the bridges were found to be failing and a weight limit was imposed along with the removal of one of the lanes from the entry slip. The need for north facing slips still remained and in 2000 plans for a complete rebuild of the junction were announced. The existing bridges would be demolished and a dumbbell interchange built which enables all turning movements to be made. The new junction opened in 2002.

All was not well however as the volume of traffic using the single lane slip roads of the new junction was underestimated. The queue of traffic leaving the M5 would regularly back up onto the motorway. A temporary extension of the exit slips was made by using the hard shoulder. Traffic leaving the motorway would now have somewhere safer to stack. This lasted until a permanent solution was found by adding traffic lights and dedicated left turn lane for northbound traffic to the junction. This proved effective and the slip roads were repainted back to their former lengths and the hard shoulder restored.

In 2020, the short section of road from the junction to the A38 was renumbered from B4008 to become part of the A430.

Routes

Route	To	Notes
M5	The MIDLANDS, Cheltenham
M5	The SOUTH WEST, Bristol, Stroud
A430	Gloucester (A38)	former B4008
B4008	Stonehouse