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    South Wales Trunk Road Agent (SWTRA)


    M4 South Wales



    The Knights Brown – Hanson consortium won a position on the South Wales Trunk Road Agent’s (SWTRA) Framework in January 2018 and was awarded responsibility for the Central Area. Covering the M4 J34-49 as well as the A4060, A470 and A465, in its first year of operation we successfully completed over 70 contracts. Work continues today at a similar rate.

    Under this arrangement the first contract we completed was the reprofiling of the westbound on-slip at Junction 34 of the M4. The scheme was given high priority as there had been a high number of accidents. Elements of the work included:

    • Replacing and constructing new sections of vehicle restraint system
    • Upgrading the P1 terminals
    • Reprofiling the carriageway to improve drainage and prevent ponding
    • Upgrading drainage in the carriageway
    • Clearing vegetation on the motorway mainline, junction gyratory and both on and off slips to improve visibility
    • Replacing four bridge joints to the Miskin river and railway bridge

    We completed the work in two phases.

    • Phase one was completed behind Varioguard allowing the slip road to be kept open while protecting our workforce from the high volumes of traffic.
    • Phase two required a full closure of the M4 so was programmed to minimise the number and duration of closures and took place under night time working.

    To meet financial constraints and to provide cost certainty, we worked closely with Atkins and SWTRA to identify savings. Through our early involvement we were able to redesign a number of elements before work began.

    We sought approval to use Hanson’s innovative 20mm Tuffgrip binder course. It was the first time approval had been granted to use this material on the motorway network and its unique properties enabled us to meet the requirement to reopen the motorway safely after each night shift,

    To close the M4 overnight we liaised closely to agree diversion routes with three local authorities as well as making sure people attending events in Cardiff City Centre weren’t inconvenienced. As a result of also being in proximity to the Swansea – Paddington mainline, we also communicated carefully to keep Network Rail informed.

    This project was shortlisted for the ICE Wales Roy Edwards Award.

    our sectors

    Knights Brown performed very well on this project in terms of quality, cost and time. The team worked very well as part of an integrated delivery team with the Employer to the benefit of the project

    - Marc Bryan, Portsmouth City Council

    Knights Brown was a great client to deal with. We felt from the very outset that they worked with us rather than for us, demonstrating real collaboration in order to minimise disruption to the port. The works were also delivered through a very challenging time, with the latter stages coinciding with the COVID-19 pandemic. Their approach to this was thoroughly professional, with health and safety the primary consideration. Working practices were strictly amended and monitored, with the project completed to the satisfaction of all involved.

    - Anisa Koci Port Master Plan Project Manager at Portsmouth International Port

    Overall a successful project with good management of the work. Site team asked questions rather than made assumptions which was good. Good communication. Would (and have) recommended Knights Brown for other projects.

    - Chris Clark, Colin Toms & Partners