Canals in Britain

The Bridgewater Canal is often thought to have been Britain's first, but this is far from the truth – although it was arguably Britain's first "pure" canal (more of which later). It was also, more demonstrably, the first of a wave of canal building that accompanied and enabled the Industrial Revolution.

Britain's first canals were built by the Romans, and were for irrigation rather than transport. The Foss Dyke, or Fossdyke, connects the River Witham at Lincoln to the Trent, and was probably built around 120 AD. This has a good claim to being the oldest canal in Britain that's still in use today.

During the Middle Ages, a number of rivers were improved to enable the transport of building materials. In 1425 Parliament passed an act for the improvement of the River Lea, which rises in the Chilterns, in what is now the oustkirts of Luton, and joins the Thames in East London.

The Exeter Canal, built in 1566, had Britain's first pound locks – recognisable as the type of lock that we see today, with a gate at either end. The first mitred lock in Britain (with V–shaped gates held closed by water pressure – invented by Leonardo da Vinci) was built on the Lee Navigation (the River Lea) at Waltham Abbey, Essex, in 1577.

By the early 18th century, river navigations were becoming quite sophisticated, with longer and longer 'cuts' (some with intermediate locks) to avoid circuitous or difficult stretches of rivers. A typical example of the canals built in this era is the Aire and Calder Navigation, opened in 1704.

The first true canal in the United Kingdom (designed on the basis of where goods needed to go, not where a river happened to be) was the Newry Canal, in Northern Ireland, constructed by Thomas Steers in 1741. In Great Britain, two waterways in the North West of England have rival claims to have been the first "pure" canal: the Sankey Brook Navigation, opened in 1757, and the Bridgewater Canal, opened four years later. The Sankey connects the town of St. Helens to the River Mersey, and (as its name implies) was originally a scheme to make the Sankey Brook navigable. It included an entirely new artificial channel that was effectively a canal along the valley of the brook, but the Bridgewater was a more "pure" canal in that it had no obvious association with any river. The Bridgewater was also, incidentally, the longest canal constructed in Britain to that date.

The Bridgewater Canal originally connected Worsley, now on the outskirts of Manchester, to the city centre. It was later extended to Leigh, on the Manchester side of Wigan, and Runcorn, on the south bank of the Mersey at the point where it becomes an estuary.

The period between the 1770s and the 1830s is often referred to as the "Golden Age" of British canals. Brindley was the leading canal engineer of his time, and he and his assistants surveyed the so–called "Grand Cross" of canals, linking the four great river basins of Britain: the Severn, the Mersey, the Humber, and the Thames. But Brindley didn't live to see this work completed; the Thames became the last of the four to be reached, via the Oxford Canal, in 1790 – eighteen years after his death.

The Forth and Clyde canal, linking those two rivers, also opened in 1790. But by the end of the eighteenth century the boom was over – about forty years after it had begun. Most British canals were completed by 1815; within ten years the smart money had moved into the railways.

© Haydn Thompson 2017