Duncan J MacLean, RHINOCEROS LTD
A comprehensive survey identified 64 graffiti sites alongthe busy M40. All presented different cleaning challenges.
The M40 motorway, which stretches from West London towards Birmingham, is one of the busiest in Britain withan average daily traffic flow of more than 100,000 vehicles.For drivers of these vehicles, roadside graffiti can be a dangerous distraction, as well as being unsightly and, in some cases, offensive.
In 2004, we were invited by Carillion plc, on behalf ofthe Highways Agency, to survey 57 graffiti sites along the M40, and to prepare a comprehensive report on how best to clean them. In fact, we identified 64 sites –and 2660 sq m of graffiti.
The graffiti was painted on bridges, underpasses and carriageway walls, and all the sites presented different process and safety challenges. For example,many sites were adjacent to watercourses, precluding the use of chemical paint removers.
Rising to the challenge
While wishing to minimise disruption to drivers, the safety of our workers was also a principal priority. So,wherever possible, we accessed the sites from adjacent land. However, more than 20 sites required hard shoulder closure, and the erection of crash cushion barriers.
We employed the Quill Falcon Quick Wet Blast system,which uses inert media (in this case garnet) to remove the graffiti. This approach is non-toxic to plant and animal life and presents zero environmental risk. By the time we had finished, all the graffiti from 145km of motorway was removed within three weeks.
Carillion, who were delighted with our rate of work and our safety procedures, asked us to return to the M40 in 2006 to carry out a similar job at a further 27 sites. This time more than 1000 sq m of graffiti was removed.
