Thornwood Avenue update: September 2023 (second update)

This fact sheet provides information about the recent ground collapse on Thornwood Avenue and the work that the Coal Authority will be required to carry out.

We understand that the ground collapse on Thornwood Avenue will be causing concern and disruption for a number of you and we thank you for your patience and understanding during the current situation. We were called on to site on Sunday 26 March due to a collapse within the road and grass area on Thornwood Avenue. We promptly secured the site to create an exclusion zone.

We have a number of processes in place to ensure public safety, these include:

  • Ground monitoring surrounding the collapse area with weekly visits to continue monitoring.
  • Ongoing in-person visual monitoring on a regular basis.
  • Remote visual monitoring.
  • Stone filling for on-going movement of the collapse.

Ground Investigations

It is important that we understand what has caused the collapse. Thank you for your patience and cooperation while we carried out these vital ground investigation works which confirmed the location and extent of the mine shaft.

In our last update we said we’d let you know when the works would be restarting. I can now confirm that our contractors will be back on site from Monday 2 October. They will be treating the mine shaft by drilling and resin grouting it. For public safety reasons, these works will require a large platform to span the location, as in the previous phase. However we will aim to maintain pedestrian access to all properties throughout. As the treatment process is complex, the work could take up to 12 weeks.

How will the works affect me?

We understand that these works are intrusive and will cause a disturbance, however they are necessary to properly treat the ground collapse. We will work to minimise disruption as much as possible, but there will be times when this is unavoidable and we will have to restrict parking and vehicular access.

Significant dates associated with movement of the platform are as follows:

Monday 9 to Wednesday 11 October – Delivery and movement of platform sections and plant

Thursday 12 and Friday 13 October – Crane on site carrying out lifting activities

To facilitate this work, we would ask that the area highlighted in blue below is kept clear of parked cars between the hours of 07:30 and 17:30 during these dates. There will be no parking between Monday 9 – Wednesday 11 October as a large telehandler will be in use and we ask that you make alternative parking arrangements on these days. There may be some very limited vehicle access though.

Image indicates area which is requested to be kept clear between Monday 9th and Friday 13th October 2023.

We thank you for your patience and understanding throughout this process and appreciate your cooperation with upcoming treatment works. We will confirm any other key dates as works progress.

Key contacts

Please contact us if there is anything you wish to discuss. The reference number for this project is P-045290.

Customer Services Team

If you have any questions about our work please call our customer services team on 0345 762 6848 or 01623 637 000 Monday to Friday 9am to 5pm or email us at

To report an emergency, please contact: 0800 288 4242 (24 hours a day, 7 days a week) You can find wider information about our work at, or see more about our priorities in our 3 year business plan and 10 year vision