The Historical Engineering plaque is part of the Institution's UK wide 'This is Civil Engineering' campaign, showcasing civil engineering projects, and is situated on the northern side of the new road bridge.
ICE Wales Cymru Chairman David Rowlands said: "I'm delighted to unveil our 'This is Civil Engineering' plaque at this historic site. The new road bridge is a key part of the Riverside Project, delivered by Alun Griffiths (Contractors) Ltd, Tony Gee and Partners; Capita; and Mott MacDonald for Merthyr Tydfil County Borough Council with funding from the Welsh Government. It is a vital link between the communities of Aberfan and Merthyr Vale."
He continued: "'This is Civil Engineering' is an Institution campaign based on plaques and banners that started in Wales and has spread right across the UK to raise awareness of the importance of infrastructure projects and to encourage young people into the profession."
The new road bridge was officially opened with the unveiling of another plaque by Lesley Griffiths AM, Minister for Communities and Tackling Poverty, in the presence of the Mayor of Merthyr Tydfil County Council Councillor David Isaac; Council Leader Brendan Toomey and Huw Lewis AM for Merthyr Tydfil and Rhymney.