Harecastle tunnel

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The Harecastle Tunnel is a ship tunnel on the Trent and Mersey Canal . It consists of two parallel tunnels, which are called the Brindley and Telford tunnels after their designers . Both tunnels only allowed one-way traffic with narrowboats . Nowadays only the Telford tunnel is passable.

Brindley tunnel

North portal of the Brindley Tunnel

The Brindley Tunnel is 2,633 meters (2,880 yards ) long , making it the longest traffic tunnel in  the world at the time. It is the older of the two tunnels and was designed by James Brindley and built between 1770 and 1777. Brindley himself did not live to see the opening, he died during construction.

The route of the canal over the hill was measured for the construction. In its course, a total of 15 vertical shafts were sunk , from which the tunnel was then driven in both directions. Steam-driven pumps were installed in order to remove the water that was constantly seeping into the excavation pits, which caused multiple flooding.

There was no towpath in the tunnel . Therefore, the boatmen had to move their boats through the tunnel by lying back on the boat roof and kicking off the tunnel walls. This technique is called legging in English . Meanwhile, the draft animals were being led over the hill on a path called Boathorse Road .

The tunnel had a clear height of 3.66 m and a maximum width of 2.74 m. In the early 20th century, the tunnel ceiling began to partially lower due to mountain damage . After partially collapsing, the Brindley Tunnel was finally closed in 1914.

Telford tunnel

North portal of the Telford Tunnel

The Telford Tunnel is 2,676 meters (2926 yards) long. Its construction became necessary when the Brindley Tunnel became more and more of a bottleneck in the late 18th and early 19th centuries due to the ever increasing boat traffic and extremely time-consuming legging . The engineer Thomas Telford was therefore commissioned to build a second, parallel tunnel. Thanks to advances in construction technology, the construction of the second tunnel took only three years and it opened in 1827. The new Telford tunnel also had a towpath so that the boats could be towed through the tunnel by the draft horses and the laborious and dangerous legging was no longer necessary. After the completion of the Telford tunnel, both tunnels were used simultaneously for opposite directions.

From the 20th century onwards, motorized boats that no longer needed draft animals were increasingly used. However, since running the engines in the poorly ventilated tunnel would have meant a risk of suffocation for boaters, an electric tug was put into service in 1914 to pull boats through the tunnel. This was in operation until 1954, from then on a large fan at the south portal ensured sufficient ventilation of the tunnel so that boats could pass it under motor power. Today's narrowboat takes about 30-40 minutes to drive through the tunnel.

At the end of the 20th century, the Telford Tunnel also suffered mining damage, which is why it had to be closed for several years. In the course of the renovation work, the towpath, which had not been used for a long time, was dismantled so that boats could use the remaining clearance in the middle of the tunnel.

Several smaller canal tunnels lead into the interior of the Telford tunnel. These connected it to the coal mine at Golden Hill and allowed both the drainage of the mine and the direct removal of coal via the canal. Small boats with a capacity of ten tons were used for this.

Web links

Commons : Harecastle Tunnel  - collection of images, videos and audio files

Individual evidence

  1. ^ AW Skempton: A Biographical Dictionary of Civil Engineers in Great Britain and Ireland . Thomas Telford, London 2002, ISBN 0-7277-2939-X .
  2. ↑ M. Salmon (Ed.): The Mechanics' Magazine, Museum, Register, Journal, and Gazette . 1841.
  3. ↑ Neil Cossons, British Petroleum Company: The BP Book of Industrial Archeology . 2nd Edition. David & Charles PLC, 1987, ISBN 0-7153-8931-9 .
  4. ^ LTC Rolt: Narrow Boat . 2nd Edition. Sutton Publishing, 1994, ISBN 0-7509-0806-8 .

Coordinates: 53 ° 4 ′ 27 "  N , 2 ° 14 ′ 11"  W