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"The Anderton Boat Lift"
The Anderton Boat Lift was built in 1875, it was built to lift barges from the Trent and Mersey Canal down to the River Weaver and back. It was in use for over 100 years until it was closed in 1983 due to corrosion.
In 1734 the River Weaver Navigation was completed, this was a route for transporting the salt from Winsford to Frodsham, where the Weaver joins the Mersey.
The Trent and Mersey Canal opened in 1777 and this provided another route, the canal runs close to the Weaver Navigation for part of its length, but then goes further south to Stoke-on-Trent.
The owners of the two waterways decided rather than compete against each other it would be better to work together, and in 1793 a basin was dug on the bank of the Weaver at Anderton, 50' higher at the top of the bank ran the Trent and Mersey and facilities were built for trans-shipping goods between the two waterways.
There were cranes, salt chutes and an inclined plane, the facilities were further extended in 1801 when a second quay built,and in 1831 a second entrance to the basin. By 1870 the basin had become a major trans-shipment interchange, with extensive warehousing, three separate double inclined planes and four salt chutes.
However, trans-shipment was time-consuming and expensive, so the Trustees of the Weaver Navigation decided that a link must be made between the two waterways so that boats could go directly from one to the other. Locks were considered but a suitable site could not be found, plus the amount of water they would use made this impossible.
In 1870 the Trustees proposed that a boat lift should be built between the two waterways, so their chief Engineer, Edward Leader Williams, was asked to draw up plans for the lift.
Leader Williams finally settled on a design which involved two water-filled caissons, these would counter-balance one another, and so require very little power to lift boats up and down. He decided that if he used water-filled hydraulic rams to support the caissons, then the weight of the caissons would be borne by the rams and their cylinders, buried underground, so a fairly light superstructure could be used.
Leader Williams appointed Edwin Clark as principal designer. The two caissons were made out of wrought iron and each measured 75 ft long by 15 ft 6 inches wide and 9 ft 6 inches deep, each one could fit two full length narrowboats or a single barge of up to 13 ft wide. Each caisson weighed 90 tons when empty and 252 tons when full of water. Each caisson was supported by a single hydraulic ram consisting of a hollow 50 ft long cast iron piston which had a diameter of 3 ft, and travelled in a buried 50 ft long cast iron cylinder wich had a diameter of 5 ft 6 inches. The superstructure consisted of seven hollow cast iron columns which provided guide rails for the caissons and supported a working platform, and an access staircase.
At the upper level the boat lift was connected to the Trent and Mersey canal by a 165 ft long wrought iron aqueduct, with wrought iron gates at both end.
The contract for construction of the lift was awarded to Emmerson Murgatroyd & Co. Ltd. of Stockport and Liverpool. Work started before the end of 1872, and took 30 months. The Anderton boat lift was formally opened to traffic on July 26, 1875. The total cost of the work was £48,428.
In 1882 one of the cast iron hydraulic cylinders burst while the caisson that it supported was at canal level with a boat in it. The caisson descended rapidly, but fortunately the water escaping from the burst cylinder slowed the rate of descent, and the water-filled dock at river softened the impact. No-one was hurt and the superstructure of the lift was not damaged. During subsequent testing, the second cylinder failed too, and the boat lift was closed for six months while sections of both cylinders were replaced and the connecting pipework, which was thought to have contributed to the cylinders' failure, was redesigned.
Volumes of traffic through the lift grew steadily through the 1880s and 1890s, but the hydraulic cylinders continued to give problems. However the main cause for concern was corrosion of the pistons. The use of canal water as a working fluid in the hydraulic system, and the immersion of the pistons in the wet dock at river level led to corrosion and "grooving" of the pistons. Attempts to repair these grooves with copper made matters worse, as this reacted electrolytically with the acidic canal water and hastened the corrosion of the surrounding iron.
In 1897 the lift was converted to use distilled water as its working fluid. This slowed down the corrosion, but did not stop it completely. Over the next few years maintenance and repairs took place with increasing frequency, each occasion requiring either the complete closure of the lift for several weeks or a period of reduced and slower operation with a single caisson.
By 1904 the Trustees faced the prospect of a having to close the boat lift for a considerable period in order to replace the hydraulic rams. The chief Engineer at the time, Colonel J.A. Saner, was asked to investigate alternative solutions. He proposed an innovative solution in which the hydraulic rams would be replaced by electric motors and a system of counterweights and overhead pulleys, allowing the two caissons to operate independently of each other. Although this system involved many more moving parts than the hydraulic system, these would all be above ground and easily accessible, so it would be easier and cheaper to mainten.
The new superstructure consisted of ten steel A-frames, five on each side of the lift, which supported a machinery deck 60 ft above the river level. The electric motors, drive shafts and cast-iron headgear pulleys were mounted on the machinery deck. Wire ropes attached to each side of each caisson passed over the pulleys to 36 cast iron counterweights, 18 on each side. Each counterweight weighed 14 tons, so that 18 counterweights would exactly balance the 252 ton weight of a loaded caisson. The electric motor was required to overcome friction between the pulleys and their bearings. A 30 horse power motor was installed, but normal operation only required about half of this power.
In addition to new foundations and superstructure, the conversion also involved converting the wet dock at river level into a dry dock and strengthening the aqueduct between the lift and the canal. The original caissons were retained, but modified to take the wire ropes that now supported them on each side.
The conversion work was carried out between 1906 and 1908. As Saner had promised, the lift was only closed for three periods during these two years, for a total of 49 days. The converted lift was formally opened on July 29, 1908.
After conversion to electrical operation the boat lift was successfully operated for 75 years. Regular maintenance was still necessary. However, the maintenance was simpler than before because the mechanism of the electrical lift was all above ground. It was also less expensive because the caissons were now designed to be run independently, so most maintenance operations could be carried out while one caisson remained operational, thus avoiding the need to close the lift entirely.
During 1941 and 1942 the hydraulic rams of the original lift, which had been left in place in their shaft beneath the dry dock constructed during conversion, were finally removed in order to salvage the iron.
During the 1950s and 1960s the commercial traffic on British canals declined and by the 1970s the traffic was almost entirely recreational, and it was almost unused during winter months.
During repainting work in 1983 extensive corrosion was found in the lift's superstructure, and it was declared structurally unsound and closed.
Restoration work started in 2001 and the lift was re-opened in 2002 using a modified version of the original hydraulic system, with the 1906-1908 external frame and pulleys retained in a non-operational role.
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