Sophia’s Dam

Hendrik Jacobus Schoeman came to Hartbeespoort in 1868. He acquired a farm along the Crocodile River and called it Schoemansrust.

Construction of Sophia Dam – the first dam in Hartbeespoort

He built his house east of the river near the Poort next to the Rustenburg-Pretoria road. Near the house was a bridge over the river. Hendrik was an innovative farmer, keenly interested in new inventions. One of his schemes that never came to fruition was an ingenious system of light rail trains connecting all the important towns agricultural and industrial and mining areas in the Transvaal. This system would have been much cheaper and quicker to get into operation than the heavy rail trains that the government was trying to achieve. But Schoeman, with all his great ideas lacked the convincing powers or the patience to sell ideas to the “important” people.

When in 1898 he again lost patience with red tape, he commissioned a certain Emil Kunst to design and build a large dam in the Crocodile River near the Witwaterpoort. The site was about 8km up river from his house and lands. The dam would hold enough water for extensive and intensive irrigation, and for a town, which he intended to call Schoemansdal. 

Hendrik Schoeman was married twice. Amazingly, both wives were named Sophia Catharina Kok, although they were not related. He named this dam Sophia’s Dam in honour of his wife. We do not know whether it was the first or second Sophia. There was a Kok living on the farm just to the west of this dam. Schoeman reportedly had many quarrels with him over water rights. We assume then that this must have been his father-in-law!

The following news item appeared in “De Volkstem” in 1898: (Our translation to English)

The Sophia-dam

A GOOD EXAMPLE

 This is the largest dam in South Africa.  It was built in the Crocodile River for Hendrik J. Schoeman, Esquire, at Schoeman’s Rest, by Emil Kunst, Esquire. The dam was built of granite stones and Portland cement and has a height of 54 1/2 feet, a width of 120 feet at the base and 17 feet at the crest. The wall contains 16 122 cubic yards of stone, weighing 71 823 510 pounds or 30 912 tons.)

The water is dammed up for 3 000 yards. The dam holds 6 650 million liters or 831 250 000 English gallons. The dam has been built without a spillway, and superfluous water simply flows over the wall.)

The dam has been built to irrigate lands and supply water to the town “Schoeman’s Dale” which is to be built in the near future, as well as for an industrial installation using 1 000  horse power. The canal is 9 000 yards long, 8 1/2 feet wide and 4 1/2 feet deep. It delivers 346 million liters of  water a day, or 43 250 000 gallons. The delivery of water is regulated by rolling sluices patented in Germany. Enough is supplied to irrigate 8 000 morgen  once in ten days (5945,6 hectares). If you reckon that one morgen can yield 30 sacks of wheat per harvest,  this means that 240 000 sacks of wheat could be harvested. This would be enough to feed 2 000 poor families well, leaving about 100 000 sacks to be sent to the market. Normally there are two  harvests per year. This would increase the income considerably.

It is quite remarkable to note that the ZAR introduced the metric system into the railway system during the nineteenth century. What they called granite was in fact local quartzite. Cement was shipped from Britain.

Schoeman’s dam would have been the largest in southern Africa, or maybe even in the southern hemisphere. This ambitious undertaking, his plans for a new town, welfare schemes, industrial developments and large-scale farming reveal his character. Unfortunately his ideas were too advanced for his time. Few were interested in his farsighted plans. He had to borrow 10 000 pounds to build the dam. In today’s terms that would amount to R100 000 000. He attempted to sell the dam to the government, but before they could reach a decision the Anglo Boer War broke out and needed all their attention. Twenty years after his death Hendrik’s ideas bore fruit, when the  Union government built the Hartbeespoort Dam.

From 1905 the then Department of Water Affairs was already taking measurements of the flows of all rivers as preparation for the calculations to design the future Hartbeespoort dam. A graph of that date’s water flow shows that at 10h20 there was a peak in the flow resulting from the breaking of the “Schoeman dam”. Some are of the opinion that this refers to the Sophias dam, but both R. Mulder and Meiring Schoeman mention that the Sophias dam already broke before 1900. the breaking of both dams was due to the same flau in construction. Both were retaining walls based on the rock floor in the river. When floods were very high the dam walls had to withstand the onslaught of the Crocodile River in flood.  There was no cladding to protect the embankment or bottom. The waterfall behind the wall picked up the soil and swept it away, undermining the foundations of the wall.

When the Hartbeespoortdam is empty enough one can see the remains of Sophia’s Dam under the railway bridge at Meerhof, (see 049). Some of the canals are still there. In one place a bridge carried the canal over the Swartspruit. Elsewhere a deep cutting takes it through a koppie. Hendrik’s son Johan, later made use of these canals. He lengthened the upper end by one kilometre and built a weir up-river to divert water into the canal.