Telford Tunnel
Due to the amount of traffic and the slow process of legging, the Harecastle Tunnel was becoming a major bottleneck on the canal. It was decided to commission a second tunnel to be built by Thomas Telford. Due to advances in engineering, it took just three years to build, and was completed in 1827. It had a towpath so that horses could pull the boats through the tunnel. After its construction it was used in conjunction with the Brindley tunnel, with each tunnel taking traffic in opposite directions.
Between 1914 and 1954 an electric tug was used to pull boats through the tunnel. In 1954 a large fan was constructed at the south portal. While all the boats are within the tunnel an airtight door is shut and all the air is pulled through the tunnel by the fan. This allows diesel boats to use the tunnel without suffocating the boaters. Today the journey takes about 30–40 minutes.
In the late 20th century, the Telford tunnel also began to suffer subsidence, and was closed between 1973 and 1977. The towpath, long disused, was removed, allowing boats to take advantage of the greater air draft in the centre of the tunnel.
A series of smaller canal tunnels are joined to the Telford tunnel. These tunnels connected to coal mines at Golden Hill and allowed both the drainage of the mines and the export of coal directly from the mines to the canal tunnel without the necessity of first hauling it to the surface. Small boats of ten tons' capacity were used in this endeavour.
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Famous quotes containing the word tunnel:
“The only way to find out anything about what kinds of lives people led in any given period is to tunnel into their records and to let them speak for themselves.”
—John Dos Passos (1896–1970)