The highest and biggest in the British Isles, the aqueduct at Pontcysyllte
is one of the most important and dramatic features on the national
2,000-mile waterway network. Built by renowned engineers Thomas Telford and
William Jessop, the aqueduct is a Scheduled Ancient Monument, a candidate
for World Heritage Status and a Grade I listed structure – widely known as
‘one of the wonders of Wales.’
The aqueduct carries the
Llangollen Canal across the River Dee, turning it into a waterway in the
sky – over 120 feet (39m) high and over 1,000 feet (305m) long. It was
completed in 1805 and took 10 years to build at a cost of £47,018. Built by
the Ellesmere Canal Company – as part of a plan to link Liverpool and
Bristol by inland waterway - the full project was never completed.
Pontcysyllte Aqueduct, however, stands as a legacy to their ambition and a
masterpiece of engineering.
One of the most innovative features of the aqueduct is Telford’s decision
to lay an iron, water-carrying trough on top of a row of stone piers. The
ironwork was supplied locally by William Hazeldine’s foundry at nearby Plas
Kynaston. Dovetail joints in the iron trough were sealed with a highly
successful combination of Welsh flannel and lead dipped in liquid sugar. The
craftsmanship of the stonework is equally impressive, with very thin masonry
joints bonded by a mortar made from a mixture of ox-blood and lime.
When the aqueduct was first opened in 1805, a cannon fired a royal
salute, and 8,000 people witnessed the first boat cross. The aqueduct
successfully linked Llangollen with the rest of the
Shropshire Union Canal system – and continues to work today. The
aqueduct originally carried coal from local mines, but it also supplied
water, taken from the Dee at Horseshoe Falls (also built by Telford) and fed
into the rest of the Shropshire Union Canal. Today the structure continues
to carry over 50 million litres of water every day to supply the water needs
of southern Cheshire.
The aqueduct remains virtually unchanged since it was opened, apart from
refurbishment to the balustrade and towpath, and more than 10,000 boats and
25,000 pedestrians cross it each year. |
