Avon Aqueduct | |
|---|---|
 | |
| Coordinates | 55°57′51″N3°39′22″W / 55.964167°N 3.656111°W |
| Carries | Union Canal |
| Crosses | River Avon |
| Locale | Linlithgow |
| Characteristics | |
| Total length | 810 feet (250 m) |
| Height | 86 feet (26 m) |
| Longest span | 50 feet (15 m) |
| No. of spans | Twelve |
| History | |
| Designer | Hugh Baird |
| Location | |
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The Avon Aqueduct is a navigable aqueduct that carries the Union Canal over the River Avon, near Linlithgow, Scotland.
The aqueduct was built to a design by Hugh Baird, with advice from Thomas Telford, in tandem with the aqueducts at Slateford and Lin's Mill, with which it shares its design. [1] [2] Telford was not convinced that the stone arches were necessary in conjunction with the iron trough, but Baird used both on all three major aqueducts. [1] Construction was carried out by Messrs. Craven, Whitaker and Nowell between 1819 and 1821, their success in building a stone bridge over the River Ouse making their tender for the contract "by far the most eligible". [3]
The aqueduct straddles the border between the West Lothian and Falkirk Council areas, so has two Historic Environment Scotland listings. [4] [5] [6] The aqueduct is a category A listed building. [5] [6]
The Barton Aqueduct of 1761, and subsequent canal aqueducts in the United Kingdom, used large quantities of masonry and puddling to obtain watertightness. [3] After the success of The Iron Bridge in 1789, however, cast iron was used by Telford on aqueducts such as Chirk and Pontcysyllte. [3] Aqueducts built in the early part of the 19th century use either puddle clay or an iron trough in no particular pattern. [7] The Avon Aqueduct uses an iron trough to achieve watertightness, as well as containing the outward pressure of the water, allowing it to be of more slender construction than a purely stone aqueduct such as the Kelvin Aqueduct. [2]
It is just over 810 feet (250 m) long including the tapered part of the canal at each end, and 86 feet (26 m) high above the surface of the river. [2] The aqueduct is carried on twelve segmental arches, each of 50 feet (15 m) span. [2] The piers, which are slightly tapered, spring into the arches at a height of 50 feet (15 m) above the river level, and the tops of the arches are 50 feet (15 m) above that point. [2] The piers are hollow, and access to the inside of the structure underneath the trough is gained by a small door 3 feet (0.91 m) high by 2 feet 6 inches (0.76 m) wide. [2] The structure is 23 feet 8 inches (7.21 m) wide at the top, and the canal is 13 feet (4.0 m) wide and around 6 feet (1.8 m) deep due to silting. [2] There are stone towpaths 4 feet (1.2 m) wide along each side. [2]
It is the longest and tallest aqueduct in Scotland, and the second longest in Britain, after the Pontcysyllte Aqueduct in Wales. [2]
The river passes under the aqueduct at the eastern end, where the aqueduct has a slight curve. [8] It can be viewed from Muiravonside Country Park.
