Context 170 - December 2021

C O N T E X T 1 7 0 : D E C E M B E R 2 0 2 1 29 RIVER SEVERN BILL KLEMPERER Repairing the Iron Bridge English Heritage undertook an extensive programme of strengthening and repair to Ironbridge World Heritage Site’s celebrated landmark between 2017 and 2020. The Iron Bridge, a scheduled ancient monu- ment, is celebrated as a symbol of the industrial revolution. Built between 1779 and 1781, it was designed, and its construction was overseen, by the ironmaster and Quaker Abraham Darby III. The parts were probably cast at the nearby Bedlam Furnace. When completed, it was the first large bridge in the world to be made of cast iron. Its success and fame led to the rapid adop- tion of cast iron as a building material. It spans the narrow Severn Gorge at Ironbridge and is a major tourist attraction within the Ironbridge World Heritage Site, inscribed in 1986. An initial laser scan survey enabled detailed 3D modelling of the bridge to an extent not previously possible. This informed scaf- fold design, identified areas requiring close inspection and enabled a full specification for repairs to be produced by the Morton Partnership, consulting engineers. Many other specialist contractors were involved in the pro- ject. The conservation aspects were overseen for English Heritage by Heather Sebire and by Bill Klemperer for Historic England. Russ Turner of Eura Conservation acted as clerk of works, archaeological monitoring was carried out by Spencer Smith of the Ironbridge Gorge Museum Trust, and the main contractor was Taziker Industrial Ltd. The first task was to build a full self-supporting scaffold with protective covering. As public access was important, only half of the deck was worked on at a time, allowing a public walkway to be incorporated.This allowed people still to cross over the river and to watch work in progress through specially built windows into the encapsulated area. Information boards explained the project to visitors, and the main contractors and English Heritage volunteers gave guided tours of the works throughout the project. The heat-shrunk polythene sheeting bonded to the scaffold allowed grit blasting of the whole bridge and further detailed inspection prior to the commencement of repairs. Advertising the new technology: ‘This bridge was cast at Coalbrook-dale and erected in the year 1779’ All photos are the copyright of English Heritage.