Coal was the power source for steam engines, which drove the Industrial Revolution across Britain. The Denbighshire coalfield was a rich supply but suffered from poor transport links. The original route of the canal from Chester to Trevor would have connected the major mining areas of Ruabon, Brymbo, Gresford and Bersham to growing industries.
This plan was abandoned however, and instead, the canal travels through the southern edge of the coalfield and into Shropshire and Montgomeryshire.
The canal boats mainly supplied local industries – limekilns, brickworks and ironworks. In the towns and villages along the way, coal became important for domestic heating and cooking.
At the official opening of Pontcysyllte Aqueduct, two empty coal barges crossed to be filled at Trevor Basin. They symbolised how the canal could move an important economic resource. Although railway transport came to supersede canals all too quickly, trade on the canal continued to increase with industrialisation in Britain. Hundreds of thousands of tons of coal moved on the canal network kept prices low.
By the twentieth century however, trade was falling. The Shropshire Union Canal’s own coal boats ceased trading in 1921. The last recorded shipment of coal on the canal was from Black Park Colliery in 1933.
Modern footage of boats delivering coal
This film shows the coal boats Ilford and Aquarius, working a traditional ‘boat and butty’ system, used on larger canals in England. The ‘boat’ is powered and tows the ‘butty’ behind it. Using this system, a crew of four could run two boats at once and move a lot more cargo.
More Information About Coal
The earliest coal mines were small. They operated with only a few workers and they weren’t very deep. This engraving of a pithead in Acrefair shows the simple headgear, which lowered miners in and coal out. It was printed in 1794, just before work started on the canal.
Black Park, near Chirk, was the oldest colliery in Denbighshire. It was first mined in the early 1600s. Thomas Ward, who also owned mines at Cefn Mawr, leased it from 1805, specifically to take advantage of the canal connection. Closed in 1949, almost nothing remains of the pit above ground.
Black Park Colliery was over a mile from the canal. A horse-drawn tramroad took the coal to a dock near Chirk. Boats, like this one in 1910, entered the dock under a bridge on the towpath, seen on the right. The bridge has since been demolished and the dock filled in.
At Trevor Basin, the Plas Kynaston Canal (seen on the right) was expanded by Thomas Ward in the late 1820s, to reach his mines in Cefn Mawr. However, most local collieries were linked to the canal by the Ruabon Brook Railway. The railway terminated at the wharf seen here on the left.
At the canal wharves, staithes were used to load the boats. These are chutes or slides, down which the coal is tipped from wagons. The boat owner then had to ‘trim’ the coal. This meant levelling it evenly across the vessel so that it didn’t lean to one side.
Mining was a very dangerous occupation. Big accidents, like the one at Gresford that killed 266 accounted for only 17% of mining deaths. Individual incidents were far more common. This gravestone is one of several for miners killed at work to be seen at Chirk churchyard. Brynkinalt Colliery was in the village.
Until 1843, women and children as young as 5 years old were also employed in mines near the canal. In 1841 mine owner Thomas Ward said that he was averse to education amongst ‘the lower orders’ as he had never known any good come from teaching them writing and arithmetic.
Coal mines produce waste by-products, dug out of the pit. Clay was often reused in brickworks. Shale excavated at Plas Kynaston Colliery brought Robert F. Graesser, a German Industrial Chemist to Cefn Mawr in the 1860s. He extracted paraffin oil and wax from it, establishing Plaskynaston Chemical Works in 1867.
Coal mines spread much further underground than the work on top. Brynkinalt Colliery was in Chirk. In time, its mines became ventilation shafts for Ifton Colliery. They were nearly two miles apart above ground but interconnected beneath.
Colliery wharves were always busy and dirty areas. Mines operated twenty-four hours a day, and it took around four hours to fill a pair of boats. This is Hednesford Colliery, Staffordshire, around 1920.
Bersham Colliery, between Chirk and Wrexham, closed in 1986, the last deep mine in Denbighshire. Although too far away to take advantage of its transport links, Bersham represents the huge industry that provided the impetus for the building of the canal. The enormous waste tip is an unmissable local landmark.