Crofton Pumping Station
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Crofton Pumping Station is a pumping station, located near the village of Great Bedwyn in the English county of Wiltshire, which supplies the summit pound of the Kennet and Avon Canal with water.
The original steam powered pumping station is preserved and still operates on selected weekends; it contains one of the oldest operational Watt style beam engines in the world, dating from 1812.
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[edit] Description
When the canal was built, there were no reliable water sources available to fill the summit by normal gravitational means. However a set of usable springs were found adjacent to the canal route about one mile (2 km) east of the summit pound, and about 40 feet (12 m) below it. Arrangements were made for these springs to feed the pound below lock 60 at Crofton Locks. Some years later a reservoir (Wilton Water) was created to enhance the supply to this pound, and this can now be seen across the canal from the pumping station.
Water from below lock 60 was taken by a culvert to the foot of a well sunk from the location of the pumping station, which is situated on the hillside more than 40 feet (12 m) above the canal. The pumps then pump this water out of the well, and discharge it into a feeder channel adjacent to the pumping station. The water then flows along this channel under the force of gravity until it reaches the summit pound about one mile to the west.
For day to day operation, the pumping station now uses electric pumps, automatically controlled by the water level in the summit pound. However the original steam driven pumping equipment has been preserved and is still operational. A single Lancashire boiler provides steam to one or both of two beam engines.
Number 1 engine, built by Boulton and Watt in 1812, is a single acting, condensing engine with a bore of 42.25 inches (1073 mm), a stroke of 7 feet (2134 mm) and indicated power of 38.6 horsepower (28.8 kW). It drives a 30 inch (762 mm) lift pump that is capable of lifting 2274 lb (1031 kg) or approximately one ton of water per stroke, at a rate of 11 strokes per minute.
Number 2 engine, built by Harvey and Co. of Hayle in 1846 and rebuilt in 1903, is a single acting, condensing engine with a bore of 42 inches (1067 mm), a stroke of 7 feet 8 inches (2337 mm) and indicated power of 42 horsepower (31 kW). It drives a 30 inch (762 mm) force pump that is capable of lifting 2235 pounds (1014 kg) or approximately one ton of water per stroke, at a rate of 10.2 strokes per minute.
An interesting feature of the pumping station is that when the Great Western Railway built its railway line through the area, it passed very close to the station and between it and the canal. Access between the canal side and the pumping station is now via a very low roofed tunnel.
[edit] History
The pumping station was built between 1807 and 1809 in time for the opening of the canal in 1810. The station was built to accommodate two pumping engines, but only one, a 36 inch (914 mm) bore engine bought second hand from the West India Dock Company, was initially installed.
In 1810 a second engine was ordered from Boulton and Watt. This engine, which started work in 1812, is the current number 1 engine, and has been the main engine throughout the steam driven life of the station.
In 1846 the original 1809 engine was replaced with a new engine supplied by Harvey and Company and built as a double-acting Sims patent combined cylinder engine. However this engine proved troublesome and eventually fell into disuse.
In 1903 the 1846 engine was rebuilt as a simple single acting engine and thus became the current number 2 engine. Both engines then continued in regular use until the 1950s, when the state of the chimney forced the removal of the top 36 feet (11 m). The reduced height chimney was unable to provide sufficient draught, and it proved cheaper to retire the steam engines and install electric pumps.
In 1968 the pumping station was purchased by the Kennet and Avon Canal Trust with restoration in mind. The building and both engines were restored, and the unrepairable boiler replaced with another of the same type acquired second hand. Number 1 engine was first successfully steamed on April 4th, 1970 and the pumping station officially reopened on the August 21st of the same year by John Betjeman. Number 2 engine was first successfully steamed on November 15th, 1971.
Initially the problem of the shortened chimney was overcome by the use of an electric fan to improve draught, however between 1996 and 1997 the chimney was repaired and restored to its full original height of 82 feet (25 m).
[edit] Visiting
The pumping station is open to visitors every day in summer. The engines are steamed on selected weekends throughout that period, and can be viewed in operation. The 'Crofton Beam Engines' website (below) carries admission details.
[edit] Location
Position: grid reference SU262622
Nearby towns and cities: Hungerford, Marlborough, Newbury, Swindon
Nearby villages: Great Bedwyn, Wilton, East Grafton, Burbage
Nearby places of interest: Wilton Windmill
[edit] See also
- Claverton Pumping Station, another restored pumping station on the Kennet and Avon canal.
