Vierfontein Dam

Visitors entering the Klipriviersberg Nature Reserve from the Northern or Mondeor Gate, will notice the weir that has been built across the spruit. Surrounding the weir are massive granite blocks that have been firmly cemented into position. At first impression one would assume that the structure was an attempt to create a small dam across the spruit. However, as innocuous as this appear at first glance, the structure is of considerable historical significance because it was destined to be a massive dam that would solve the water supply problem of a burgeoning Johannesburg in the late 1800’s. Discovery of gold The discovery of gold on the Oosthuizen farm, Langlaagte in February 1886, triggered a world-wide reaction that would result in an unprecedented influx of people into a Republic that was practically unknown. People of all cultures, languages, colour and religions arrived in the burgeoning gold town, named Johannesburg. They arrived with only one purpose in mind – the prospect of making a fortune. The influx of people into the area was so great, that the original tent town quickly grew into a town with buildings, shops, bars, taverns, music halls, more taverns, houses of ill repute and even more taverns. Hardened prospectors, who had battled disease and the elements in the Lydenburg and Barberton gold mining areas, many with minimal success, deserted their claims and flocked to the Witwatersrand. Their counterparts from the Kimberley diamond fields also joined the rush. People arrived in their hundreds on a daily basis using every imaginable form of transport. So, it was not surprising, that the rapid population growth soon started having a detrimental affect on the make shift public amenities.

The entrance to Klipriviersberg today. To the right as you look at the pic is the cliff face which was already blasted to make way for the “left” wall of the proposed dam. To the left behind the tree was the opposite cliff face. Photo by Gary O'Bryan

Shortage of water supply

One of the more serious problems that the growing town experienced was a shortage of a regular and safe water supply. At the outset, the Transvaal Volksraad (Parliament), under the leadership of Paul Kruger, where unimpressed by the influx of “uitlanders”. Equally they soon realised, that there was very little that they could do to stem the tide of fortune hunters. While they grudgingly accepted their presence they also resolved to make the uitlanders’ stay as uncomfortable as possible. President Paul Kruger firmly believed that the discovery of gold, like Lydenburg and Barberton was a flash in the pan and that the prospectors would soon become disillusioned and leave. On that basis he was reluctant to persuade the Volksraad to commit funds to supply amenities that would make Johannesburg a permanent fixture.

However, when the government started seeing the positive financial benefits, that were accruing, from the taxes that were being levied on anything to do with gold, there was a marked shift in their attitude. As Johannesburg grew, water or the lack thereof soon became a major problem in the town. Organisations such as the Johannesburg Waterworks Company were hard pressed to cope with the demand for this precious commodity. At times the shortage was so acute that some residents were obliged to wash in “mineral water” that might have been better used in a glass of something stronger. By the late-eighteen hundreds water consumption in Johannesburg had rocketed to 5-million gallons a day and the need for some form of regular water supply was assuming critical proportions. While initial representation to the Volksraad to find a solution to the problem fell on deaf ears, Kruger eventually managed to persuaded the Volksraad to appoint a special committee “to provide a reliable water scheme for Johannesburg.” Vierfontein Farm selected as site for dam A well known engineer, by the name of Hamilton Smith, was given the task of finding a suitable site where a dam could be built. Of all the sites that he considered the one on the farm Vierfontein was the most suitable. It was close to Johannesburg, it had a strongly flowing, permanent stream and there was a gap in the surrounding hills where a wall could be erected. The perennial stream was fed by four tributaries that where, in turn, fed by strong natural springs. There was also an adequate deposit of granite that could be used to construct the massive wall of the dam.

Shows the progress that was made with extensive blasting to flatten the Cliff face to line up the Left wall. In the foreground are the blocks that were placed to create the diversion weir and coffer dam. Photo by Gary O'Bryan

The situation and the plans for constructing the dam was approved and the Vierfontein Syndicate was established. Five mining magnates, Sir Lionel Philips, C.S. Goldman, H. Crawford, C. Malcomess and E. Lippert, where elected to the board and the syndicate proceeded to buy the farm Vierfontein. The construction of the dam was delayed for several years but before the close of the century work on the dam begun in earnest. Huge slabs of Granite were quarried from deposits of that had been found in an area just north/east of the Anglican Church, in Mondeor. The slabs where transported by an overhead cable and pulley system and deposited in an area above the dam site, where they were “dressed” and lowered into position. (Dressed and undressed slabs of granite together with massive pitons that have been driven into the rocks can still be seen in an area above the dam.) As a matter of interest, this style of construction became known as “Cyclopean Masonry Construction.” A well known engineer by the name of E.J. Lashinger, was appointed to oversee the construction of the wall. The first set-back that the project suffered was that the bed-rock that was to support the foundations of the wall, was found to be very soft and because of this the builders had to excavate a further 50 ft below the surface of the veld. Having reached stable bed-rock the construction of the massive 30 foot wide wall got under way. The dam wall, which was designed to be 40 foot high, was successfully anchored to the hill on the western side of the spruit. However, when construction reached the Eastern side the rock structure was found to be too soft. Lashinger decided that the solution to the problem was to dig a hole to the same depth as the foundations, cast a pillar in the hole and anchor the wall onto the pillar. Workmen started digging the hole but struck water, at an unknown depth and the hole filled with water. Anglo/Boer War intervenes construction At this point in time providence played a part in the construction of the dam because the Anglo/Boer war started. The British workers on the site returned to Natal and the Cape, the Boer workers returned to their homes to joined their local Commando and the labourers returned to their homelands. After the war the new government reassessed the feasibility of continuing construction of the dam and they came to the conclusion that further work on the structure would be uneconomical. Having taken the decision to cease building the dam the new government decided to build the Barrage on the Vaal river and pump water to Johannesburg. Vierfontein dam project abandoned.

The farm Vierfontein was eventually sold to a Mr. Latten who renamed it Ormonde and it was not too long before the only evidence of the proposed dam was a deep quarry and a wall that was incomplete. Had the Vierfontein Dam been completed Johannesburg would have boasted a lake that stretched over 2 square miles and was 50 ft deep. The suburbs of Mondeor, Winchester Hills and Zuideroord would never have existed. The hole that was meant to anchor the wall became known as Silent Pool and it has been the focus of many urban legends. Rumour has it that it is bottomless, people who have braved the ice cold water have, reputedly suddenly disappeared without trace, a stolen motor car was said to have been driven into the pool. This too disappeared without a trace. Eyewitnesses have sworn that all manner of spirits emerge from the murky waters at full moon. There have been several reports of people committing suicide by throwing themselves into the water.

A front view showing the progress on the initial coffer dam weir. Photo by Gary O'Bryan

And there are probably many more stories. However, perhaps the real mystery of Silent Pool is that the level of the water never drops regardless of how dry the season is. Read Eric Rosenthal's article on the Vierfontein Dam published in the Sunday Times in about 1935.