The Erskine Bridge is a major crossing of the River Clyde connecting Renfrewshire and West Dunbartonshire. Opened by HRH Princess Anne on the 2nd July 1971, it is the westernmost crossing of the river.
Discussions on the need for a downstream crossing of the Clyde began in the mid-1930s. It took almost 30 years of planning before a final design was approved. The bridge is a two lane all purpose dual carriageway with cycle/footways at either side. At its highest point, the bridge has 45 meters of clearance allowing large vessels to proceed upstream to the shipyards at Govan.
Plans for a bridge across the River Clyde at Erskine were first discussed in the late 1930s. Construction finally began in 1967, with the bridge completed and opened to traffic in July 1971.
The need for a satisfactory traffic route across the River Clyde at Erskine was recognised for several years before the bridge was completed. As early as the 1930s, dissatisfaction with the existing Erskine Ferry service between Erskine and Old Kilpatrick had become widespread. The generally expressed view was that a high-level bridge should be erected to deal with the ever increasing volume of traffic.
In 1955, a series of meetings were held between representatives of the adjoining local authorities to discuss an improvement of the river crossing. They subsequently formed the Erskine Bridge Joint Committee, and it held its first meeting on the 25th March 1963. The Joint Committee set up a technical panel which recommended the carrying out of an aerial survey and the production of contoured maps necessary for detailed design purposes and boring operations on the proposed site.
The Erskine Bridge Joint Committee appointed Freeman, Fox & Partners as design consultants for the new crossing in December 1963. They prepared a report with several recommendations, submitting it in September 1964. A cable-stayed, steel box girder bridge, with a 1,000 foot main span was proposed, with roads connecting to trunk roads on either side of the River Clyde. Given the anticipated cost of the project, the Scottish Development Department took over from the Joint Committee in September 1965. Shortly after, WA Fairhurst & Partners were commissioned to provide a design for the foundations and piers of the new structure.
Erskine Bridge Construction Summary
Erskine Bridge & Approaches
A898 - A82
2nd July 1971
The designer of the Erskine Bridge was William Brown, a renowned structural engineer and bridge designer. From 1956 to 1985, he was a key member of Freeman Fox & Partners. He was particularly talented in the field of suspension bridges, and is credited with inventing the aero-foil shaped cross section for bridge decks, an invention created to combat an array of wind conditions.
The project comprised four separate contracts. The first was for the bridge foundations and substructure, valued at £720,000 and let to Christiani Shand Ltd. The second covered the bridge superstructure and main steelwork and was let to Fairfield Mabey Ltd with a value of £4.5 million. Today these contracts would have a value of around £70 million. Contracts three and four were for the construction of the north and south approach road system - see M898 and A82 for more.
Construction began on site during April 1967, with the main focus being on bridge foundations. A formal ceremony was held on 6th June. The bridge is composed of two concrete abutments and fourteen concrete piers. These are supported on piles, which in some cases, were driven to depths 190 ft (58m). When piling works were completed over 43,000 ft (13.1km) had been driven. Piers are diamond shaped and vary in height from 22 to 175 feet (6.7 to 53m). This profile was developed by WA Fairhurst himself.
The bridge superstructure consists of a continuous steel box girder with a cable-stayed main span of 1,000 ft (330m). It varies in width from 97 ft 6inches (30m) to 102 ft 6inches (31m). Clearance above the high water mark of the Clyde is 180 ft (55m). The bridge is 4,334 ft long (1321m) made up of the main span, two anchor spans of 360 ft (110m) and twelve approach spans each of 224 ft (68m). The total weight of all steelwork is around 11,000 tonnes.
The road surfacing is a type of mastic asphalt which is laid directly onto the steel deck. The bridge is provided with footways and cycle paths on each side, and these can be removed to provide and additional traffic lane should they ever be required.
The main steelwork was erected from both ends simultaneously, with completion being near the centre of the main span. A cantilevering process was utilised which is illustrated below. Each girder was loaded onto a trolley and winched out to the edge before being lowered into position. Temporary props and cables were used during this process to ensure stability. This procedure led to the collapse of the Cleddau Bridge in Wales and the West Gate Bridge in Melbourne during their respective construction phases in 1970. The Merrison Committee was set up by the UK Government to determine the root causes for the failures and a number of recommendations and bridge strengthening followed as a result.
As part of contract four an administration building and toll booths were constructed. The building, which is still used as a maintenance depot originally provided facilities for toll workers and maintenance staff as well as rapid response breakdown vehicles, CCTV monitoring and traffic control facilities. The bridge tolls remained in placed until April 2006, with the final cost being 60p.
This article was first published in November 2020.