M4 Brynglas Tunnels

M4 Brynglas Tunnels Refurbishment




The Project

The Brynglas Tunnels on the M4 near Newport are critical to the Welsh economy and it is vital that they are efficiently maintained. Commissioned by client, Costain, Toppesfield completed resurfacing of the tunnels in 2018, which form part of a wider scheme of major works to structures, bridges, and tunnels which will improve the motorway.

Our Work

Starting in June 2017, the 12-month resurfacing works included four weekend closures, Friday 21:00 to Monday 06:00. During this period full rehabilitation works were undertaken to both tunnels which included the planing of existing asphalt and composite pavement as well as laying 4,780 tonnes of asphalt.

In addition, we laid four layers of Warm Mix asphalt technologies, including the first ever use of Warm Mix EME2 binder in Wales. The reduced mixing temperature of Warm Mix means a significantly reduced cooling time, allowing for increased productivity where working windows are restricted.

Results & Achievements

  • Additional installation – 4,000 m2 of HRA & PCC’s and 13.500m2 of Thin Surface Course Systems on M4 adjacent to the tunnels over 20 night possessions.
  • Collaborative Planning – Working with key stakeholders, main contractors and supply chain, ensured that the critical re-opening of the M4 was met without delay.

“Brynglas Tunnels was a very complex and demanding challenge. The concept and design of the delivery involved meticulous planning and coordination. Toppesfield provided the professionalism and support to make this a very successful project. Working through adverse conditions and logistic challenges delivering nearly seven hundred tonnes without defect or delays over eight, thirty-four-hour closures. The support provided by their management team was second to none with thorough attention given to safety, quality and delivery.”

Phil Davies, Project Director, Costain

To find out how Toppesfield can add value to your project contact estimating@toppesfield.com.


Contact Toppesfield

Call 01473 829129 or email estimating@toppesfield.com to speak to a member of our team and discuss how we can add value to your next project. We’re always happy to answer questions and meet potential customers.