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‘…a most obnoxious place’

Robert Harris reveals Sherborne's somewhat unsavoury history before the Castleton Waterwheel and the steam engine which replaced it

Tucked away just off the A30, along Oborne Road, on the eastern side of the Dorset town of Sherborne is the Sherborne Steam and Waterwheel Centre. The pump house which contains a 26ft waterwheel and around which the museum is centred was originally built in 1869 to supply clean water to the town, a task it continued to do till 1959. Following removal of virtually all of the pumping equipment in 1969, the building was left semi derelict until 1980, but since that time has been restored and a visitor centre for the museum established.

The E S Hindley factory at Bourton, near Gillingham, from where the new engine for the Sherborne Steam and Waterwheel Centre came

In 1829 a gentleman from Salisbury visited Sherborne, and was not impressed. He wrote to his father ‘The lower part of Sherborne is a most obnoxious place. The stench in Half Moon Street is such as to cause ordinary gentlemen to vomit and ordinary ladies to be overcome by attacks of the vapours. Those persons living in this part of the town have become so used to this awful stanch that they go about their daily work as if living in the middle of a fragrant flower meadow’. At that time Half Moon Street had a very deep sewer in it – so deep in fact that the residents complained that their wells drained into it. The Town Council’s solution was to dig their wells deeper with the result that the sewer drained into their wells. The deep sewer drained untreated sewerage, including the output of several slaughterhouses, into the river Yeo.
Under the Public Health Act of 1848, every borough which had an annual death rate of 21 or more per thousand of the population, was ordered (amongst other things) to set up its own water works, in order to ensure a supply of fresh, clean water. Sherborne at the time had a death rate of about 22/23, which subsequently went up to about 62 – so over a period of five years without an adequate supply of clean water one third of the population would have died of water-borne diseases. Sherborne Local Board of Health held its first meeting in September 1851. Its first priority was to supply clean drinking water to the people of the town. Initially there were three possibilities. The first plan was to bring water from three large springs to the north of the town; this plan failed because the supply was inadequate. An attempt to pump water from boreholes at Castleton to the Golden Ball Turnpike Reservoir using turbines was also unsuccessful as the turbines used were not able to produce the head of water required to drive it 230 feet up to the top of the town. The next scheme was to use a steam engine at Castleton as a temporary measure, but that was rejected as being too costly at the time. Eventually the Board of Health employed an engineer named John Lawson to draw up a scheme to pump water from the Castleton boreholes to the reservoir. His first step was to carry out a full survey of the town, and the fascinating original of his plan, which measures some eight feet by thirteen feet, now hangs in the Council offices in Newland. Copies of parts of this can be seen at the Steam and Waterwheel Centre. Lawson put forward his proposals in January 1868; they involved using a waterwheel to pump water from two new boreholes at Castleton up to the top of the town.  His plans were accepted, and the system was installed with great speed, beginning to pump in December 1869. The total cost of the installation was £2,987.18s.6d, and was capable of delivering over 7800 gallons of water an hour to the reservoir.
As constructed the waterwheel was unusual in that it had three feeds, one at the top, one slightly lower (‘breastshot’) and the third lower still. This is almost unparalleled. The top feed came from a leat which had served Castleton Mill; Castleton Mill had been demolished to make way for the new railway from London in 1860. The central leat brought water underground from the lake at Sherborne Castle, but is no longer used. The wheel is now powered by the lowest leat fed by the Oborne stream. When the top leat was in use, there would have been about two tons of water in the wheel’s buckets at any given time, and this was sufficient to power the pumps. The wheel has a diameter of twenty six feet making it one of the largest in the south of England. Its design incorporated ‘ventilated buckets’ which had been invented by William Fairbairn. A common problem with unventilated buckets, especially when constructed of metal, was that with the wheel under load and water pouring into the buckets, the displaced air is compressed and the water blows back. The Fairbairn design has a vent at the rear of each bucket which allows air to escape, so that the buckets fill more efficiently.
The waterwheel was connected to lift pumps which pumped Sherborne’s water to the Golden Ball reservoir at the top of the town, from 1869 to 1959.  It was generally very reliable but was damaged on one occasion, in November 1897 when, after very heavy rain, the Oborne stream flooded the area around the pumphouse to a depth of three or four feet. The action of the floodwater in the wheel pit caused damage to both the pit itself and the water wheel, which had to be repaired. A back up gas engine was installed at the same time at a cost of £250.10s.6d although this appears to have been little used over the years.

Manhandling the new flywheel into position before installing it

Some seven years after the wheel was installed, a steam powered pumping station was set up at Castleton because the water wheel driven pumps could no longer cope with the increased demand of the whole of the town. The steam engine for this was built by E S Hindley of Bourton, near Gillingham and it drew water from new boreholes. However this engine was costly to run, especially before the railway interchange at Templecombe was constructed, because coal had to be brought in by horse and cart from South Wales or from the Somerset coalfields – a three day haul. Eventually with the construction of the Templecombe interchange the cost of coal dropped enormously. Even so the steam plant was very expensive to operate when compared with the water wheel. The secretary to the Sherborne Urban District Council reported in 1869 that ‘The waterwheel driven pumphouse costs us one and one quarter pounds of grease per month and the attendance of one man for one half hour per day. For this small cost it pumps water for 24 hours per day. The steam driven pumphouse costs us six and three quarter tons of coal per week and the attendance of two men at all times that the engine is under steam.’
In 1959, the wheel was taken out of service partly on account of government legislation, but also because its pumps were beyond economic repair. In 1969, they, with other items of machinery including the gas engine, were taken away by the scrap man, but the wheel remained in place – chiefly because the gentleman concerned could not be bothered to dismantle it. It gradually degenerated into a poor state.

The eleven-foot diameter flywheel in situ

In 1975, a group of volunteers saved the old pump house building from demolition by the simple expedient of obtaining listed building status. The pump house building has since been restored, and a new sluice gate installed. A visitor centre has been established, and the museum opens for ten Sundays each summer. In 2008 the Centre completely rebuilt the water wheel, which had become seriously rusted and was in a state of collapse. The new wheel can be seen running on open days.
The steam engine had been scrapped in 1928, but the Sherborne Steam and Waterwheel Centre managed to locate a similar Hindley engine, which had previously run the at the brickworks in Gillingham. This engine is a large single-cylinder, double-acting horizontal engine, which has an eleven foot flywheel that weighs in at about two tons. It was kindly donated to them and is now in full working order. A period engine house has been constructed to accommodate it and its boiler, and to provide a museum about E S Hindley. The engine will be running under its own steam on open days.
The Sherborne Steam and Waterwheel Centre is well worth a visit if you are in the Sherborne area. It occupies a pleasant site with picnic facilities. The museum has its own website, from which details of opening and membership of the support association can be obtained at www.sswc.org.uk

The period engine house built to house the new engine and its boiler

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