The history of the Maidenhead Bridge
When it was built, Isambard Kingdom Brunel’s Maidenhead Bridge over the River Thames boasted the flattest yet widest brick constructed arches in the world.
Historical timeline of the Maidenhead Bridge
- 1835: 31 August, the Great Western Railway is authorised by an Act of Parliament to build the railway line between the cities of London and Bristol.
- 1839: 1 July, the Maidenhead Bridge is opened.
- 1841: 30 June, the Great Western Railway London to Bristol main line is opened throughout.
- 1861: the line from London to Bristol is converted to mixed gauge track.
- 1890-1892: the Maidenhead Bridge is widened on both sides by Sir John Fowler.
- 1892: 20 May, the last of the GWR broad gauge tracks are lifted.
- 2009: the electrification of the lines between London (Paddington) – Bristol – Swansea is announced.
Design criteria
The London to Bristol main line crossed the River Thames via the Maidenhead Bridge. Since the Thames was used by barges, the Thames Navigation Commissioners required that neither the channel nor the towpath be obstructed, allowing only one pier in the river. Brunel designed the bridge to maintain minimal gradients on the line (the inclined approaches are only 1 in 1,320, or 0.076 percent). This design ensured that the towpaths on each riverbank remained uninterrupted for bargemen and took advantage of a small island for the middle pier.
An engineering sensation
Built entirely of brick, the bridge had two shallow spans over the river, with a rise of only 24ft (7.3 meters) and an unprecedented width of 128ft (39 meters). Its design caused an engineering sensation when completed. During construction, wooden scaffolding was used to support the masonry arches. The Great Western Railway directors didn’t trust Brunel’s design and insisted the scaffolding remain in place initially.
Secretly, Brunel arranged for the timber frame to be slightly lowered, knowing the bridge would remain solid without it. Eventually, the timber frame was washed away by strong winds or a river flood, according to different accounts. The bridge remained standing and was immediately recognised as a triumph of engineering on the Great Western line.
Bridge widening
When the bridge opened on July 1, 1839, it carried two 7ft (2.14 meter) broad gauge railway tracks. As traffic to and from London increased, mixed gauge tracks were added between London and Bristol in 1861. From 1890 to 1892, the bridge was widened on each side to carry four standard gauge tracks, supervised by Sir John Fowler. The width increased from 30ft to 57ft 3in (9.1 meters to 17.5 meters). This work was done so carefully that the bridge’s outward appearance remained almost unchanged.
Did you know?
The painting, ‘Rain, Steam and Speed’ (1844) by J W M Turner, shows a Great Western Railway broad gauge locomotive and train passing over the Maidenhead Bridge.