ARTICLE: A SHORT HISTORY OF THE DESALINATION PLANT…
By Ken Denholm, published in the St Helena Herald 27th February 2004
During the Anglo – Boer war of 1899 -1902 in which some 6,000 Boer Prisoners of war were sent to the Island of St Helena, the decision was made to build a Desalination Plant at Rupert’s Bay for supplying fresh water to the largest prisoner of war camp on Deadwood Plain. By the time that the first Boer prisoner arrived on Deadwood Plain in April 1901, the construction of the Desalination Plant had already began at Rupert’s Bay.
The history of Desalination goes back a very long way in world history. In fact it was recorded that this very ancient notion was described by Aristotle as an evaporating method used by Greek sailors of the 4th century B.C for desalting sea water. During the 19th century steam-powered ships created a demand for non-corroding water in their boilers. The first patent for a Desalination process was granted in England in 1869 and in the same year the first Desalination plant was built by the British Government at Aden to supply ships calling at this Red Sea port.
The existing technology required a very large amount of energy and was very expensive, for which reason it was only used where sources of fresh water were not economically available. Certainly in 1900 when St Helena was selected as a holding centre for large numbers of Boer prisoners of war, it had limited reserves of fresh water to cater for the camps that were set up, and for this reason the decision was made to build a Desalination plant at Rupert’s Bay which, at that time, had very few residents.
There appears to have been very little if any publicity for the building of this plant, but the fact that it was a wartime project may account for that. The Eastern Telegraph Company were still active at Rupert’s Bay where they had brought the Submarine Cable ashore in 1899, but within a year or so, they shifted their Cable Base to new headquarters at the Briars. At Rupert’s Bay they had a miniature railway from the landing jetty to transport coal to a steam haulage engine which was used to haul cables to and from the cable ships.
The first construction of the Desalination plant probably began early in 1901 under the supervision of the Royal Engineers, and no doubt for the specialised equipment there were representatives from the companies who supplied it. As has been mentioned the first plant of this type had been built at Aden in 1868 and now this one on St Helena was a very adventurous project for the little island. Unfortunately as will later be shown, not all factors were apparently given enough consideration before the plant was built.
It appears that good progress was made in erecting the plant, and from the weekly newspaper ‘St Helena Guardian’ of 27th June 1901, there is a good account of the inauguration ceremony for what they termed the water condensing works:
There was an interesting gathering at Rupert’s Valley on Friday afternoon last on the occasion of the inauguration of the water condensing works at that place. In addition to the Royal Engineers and those connected with the work, Mr Miller, the construction engineer received as guests a number of our Townspeople including his Excellency the Governor [Governor Sterndale], Lieutenants Jack and Burgess of the Royal Engineers, staff of the Eastern Telegraph Company, etc.
The Chimney is a splendid piece of work constructed of bricks and erected under the direction of Mr Corfield who came out with Mr Miller to undertake the work. The platform on which the huge boilers for the condensing plant are to stand is in course of completion and in that short time the placing of the boilers and fitting up to the machinery will commence which will prove an interesting sight. During the afternoon some photos of the plant and guests were taken and everybody spent an enjoyable time.
One of the photos shows the guests near the chimney and other items of the plant. The chimney was built from imported cream Bricks and was nice looking structure with the Furnace built around its base and forming a platform for the two boilers serving the condensing plant. In this photo, the chimney and one of the boilers were both smoking but this was apparently done only as a feature for the inauguration ceremony, as the plant had not began operating.
From the St Helena Guardian of 29th August 1901 there is a good record of the equipment that was being installed at this Desalination plant, all of it having been designed, purchased and shipped here from the Cape. In addition to the chimney with its 50ft high smoke-stack having a 3ft 6in opening at the top, there are two boilers each 5ft 9in diameter by 20ft long, with an internal Flue Tube 3ft in diameter. Steam for the condensers is led over in suitable pipes fitted with controlling valves and the vaporised water finally led away in pipes to a shallow brick tank of capacity to hold a days run of the plant.
Two smaller boilers each 4ft 6in diameter by 10ft high provided steam for the running machinery which was manufactured by the well known firm of Tangyes Ltd, Birmingham, England, through their agents in Cape Town. From the storage tank at Rupert’s Bay, fresh water was pumped up to the prisoner of war camp at Deadwood Plain by a set of Duplex high pressure pumping engines, these being supplied in duplicate, through a 2½ diameter main pipe more than 2 miles long, the vertical height of the lift being about 1,600 feet. Mention has to be made of the fuel that was used to fire the furnace of the Desalination plant, and initially this was local firewood. St Helena has never been endowed with extensive Forests, and what had existed at the time of the East India Company occupation in 1659 was very much depleted by the time it became a British Crown Colony in 1834. Later in the 19th century a considerable area of Forest was planted, although at the time of the Boer War the Island was scarcely in a position to supply the massive amount of firewood that the large furnace at the Desalination plant would demand. There does not seem to have been any investigation as to whether there would be continuous supplies of Firewood on hand. A stockpile of coal in the coal yard at Jamestown Wharf was maintained but this had to be reserved for bunkering the steam ships that called. Anyway construction of the plant was carried on , with the skilled work performed by sappers of the Royal Engineers assisted by Boer Prisoners of war. Some references to the project named it the ‘Water Condensing Works’. On 24th August 1901 there took place an interesting function at which the fires were lit in the large boilers for the first time and the Machinery in general was submitted to a test run for the first time. This was obviously not a trial for pumping the Desalination water up to the camp on Deadwood Plain, but it appears from the Records that firewood was already being imported as evidenced by the ‘St Helena Guardian’ of 27th June 1901 in which it was reported that two ships have brought in a cargo of 200 tons of firewood and more was to follow.
Unfortunately as firewood was the main source of cooking fuel for the Island people, many poor families were unable to afford it. Nearly six months after the inauguration ceremony, the St Helena Diocesan magazine of November 1901 described the plant as still in the course of erection, but very soon it was to be given a trial, which although said to be satisfactory, its working was not prolonged and by the time peace was declared in June 1902, there was simply no reference to the plant by the local press.
Perhaps as it was a wartime project the Government declined to make any announcement. In April 1902 the St Helena Diocesan magazine described firewood as being somewhat scarce on the island and mentioned that Boer prisoners were carrying it back to their camps. In November 1902, after all the Boer prisoners of war had been repatriated home by August, a notice in the St Helena Guardian announced that all the effects at Deadwood camp were up for sale, so as the camp had closed, the Desalination plant had certainly long been closed down. Subsequently all that remained of the plant was the high brick chimney. The two smaller boilers apparently were on the site for a long time and it seems one of them was eventually buried there, but the other one has survived to this day.
F or a long time after being moved to a vacant site on Land where the Rupert’s Bay Anglican Church now exists, it lay for many years as a surviving relic of the desalination plant, but only a few years ago it was again moved and dumped on waste ground below Bunker’s Hill where a new quarantine Station has been built in upper Rupert’s valley. This very rusty old boiler of cylindrical shape and which has survived for well over 100 years is about eleven feet in length and five feet diameter. It is made of 3/8 of an inch thick steel plate, but there is no sign of who manufactured it. From some research on boilers it was found to be what is known as a fire tube boiler, meaning that it contains an arrangement of tubes which are heated directly from the furnace and pass through the main body of sea water that it is fed into boiler from storage tanks and heated by the fire tubes each of which has an escape opening in the boiler casing to prevent the rise of inaccessibly high temperatures. Welded to this boiler on a steel frame are two 9in diameter steel pipes running the full height of the boiler about 6ft apart, with the boiler in the upright position and standing on the furnace, these pipes may have been intended to allow the escape of excessive heat and smoke. Although the other smaller boiler has not survived it can only be assumed it was the same. Otherwise except for the large brick chimney, which still exists in very good order, there is virtually nothing else that can be said to have belonged to the desalination plant. No record exists of the two larger boilers. In 1984 when the decision was taken to move the fuel storage depot from Jamestown, what became known as the Fuel Storage Farm began being built at Rupert’s Bay. This involved a large number of Oil and Fuel storage tanks being built and unfortunately for the history of the desalination plant of 1901 the entire site together with a lot more land that was acquired for building the Fuel storage farm. As mentioned, Rupert’s Chimney was also acquired and then the entire area was fenced and strictly prohibited from entry by the public, so that entirely negates any more research on the Rupert’s Bay Desalination plant. Of the plant for the condensing works, it can only be imagined what that was in its position above the boilers and as nothing has survived it is all a matter of conjecture. Of the pipeline from Rupert’s Bay up Rupert’s hill to Deadwood Plain we know a little more. At some time after the Boer war from 1902 it was eventually taken up and used to distribute water to some areas including from Black Bridge to various garden allotments. The original route the pipe took to reach Deadwood Plain became known as the Pipe – Path after it was taken up, and was later shown on the Government Map of St Helena in 1983. Some old relics of the desalination plant lie buried under rubble on vacant land near Rupert’s Bay Anglican Church. Some relics in this rubble have come adrift from the heap and one has the following in raised letters on the Ironwork – vig- EX PRESSURE PUMP – this might have been the pump used to lift the water from the desalination plant up to the Boer Camp at Deadwood Plain. There is also another relic that appears to be part of a pump with raised letters on the Ironwork as follows: – TANOYES DUPL. However there must have been a lot of equipment that simply disappeared. Of several maps made of St Helena during the 20th century, a Government map of 1904 shows the condensing station at Rupert’s Bay and the pipe path. The Admiralty Map of St Helena in 1922 shows only the chimney and the pipe path.
The 1933 map of St Helena also shows only the Chimney at Rupert’s Bay and the pipe path. A map of St Helena in 1966 by Miss Irene Thomson shows the condensing station at Rupert’s and the Pipe Path. Finally the 1983 Government map of St Helena shows only the chimney at Rupert’s Bay and the pipe path. The 1966 map of the above was the last to show the condensing station as such.
Actually the St Helena Diocesan Magazine of April 1902 referred to the project as ‘Condensing Works’ but that was only part of the desalination plant.
The historical reference to ‘Condensing Station’ was used on two of the above-mentioned maps of St Helena. It was apparent that no 20th century works of history have given any account of the Rupert’s Bay desalination plant, but it is possible that one may yet surface. At present there does not appear to be any relics of this plant in the Jamestown Museum, apart from Rupert’s Chimney, which is inaccessible within the prohibited area of the Bulk Fuel Farm, the old boiler is the only other relic and which has been dumped at upper Rupert’s Valley under a high cliff of loose earth and stones that will probably result in it eventually being buried as apparently happened to the other boiler long ago. If funds could be found for the removal of this surviving boiler and its mounting in an annexed section of the museum it would surely be a very significant exhibit.
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