Gerhard Minnebron
Not a town or village, not even a settlement, but its a place of interest thus I decided to include it in my collection. It is situated near the road between Potchefstroom and Carletonville, the R501, about half way in between. GPS coordinates: 26.4796S 27.1518E elevation: 1415m
The Fountain
Its not just a trickle coming out the mountain, its a stream that hardly changes with the seasons and is given as 61 Ml (mega litre = 1 million liter = 1000 m3) per day. That would be about 2500 m3/hr. Interesting that the water flow was measured for the first time in 1886, than it was found to be 1.3 million gallons per hour, which translates to 5900 m3/hr. Does that mean the flow has reduced over time? I don't think we can come to that conclusion from just two data points, we need more numbers. Its a lot of water, in a semi dry country like this an absolute asset.
What you see in the picture is not the actual fountain, its the lake formed by the dam wall built to divert the water into the irrigation channel. One has to swim out (in the picture, by the way, is me) to see the water coming in from the side and bubbling in from below.
The big question, of course, is where does the water come from? To the east is the mountainous Gatsrand with dolomite underlaying and I would think that this is the catchment area for this stream.
And why is it called Gerhard Minnebron? This is because of the first occupant of the farm: Gerhard Breytenbach.
History of the place
On the farm is a Voortrekker graveyard. The oldest grave is marked by a replica of the original gravestone and reads (translated): "Hendrik Lambert Bronkhorst born on the 27th February of the year 1768 died on the 6th January of the year 1841", the last digit could possibly be a 7. It stands to reason that the Voortrekkers would very quickly occupy a source of continuous fresh water like this one. The first trekkers arrived in the area to establish Potchefstroom in 1838.
The farm was first occupied by Gerhard Breytenbach in 1838. One of the gravestones is of Jacob Johannes Breytenbach who lived from 1832 to 1892, it is possible that he was a descendant of Gerhard.
And Emil Holub was here, in his book: 'Sieben Jahre in Süd Africa' printed 1881, he reports on his first trip in 1873 from the diamond fields (Kimberley) to Wonderfontein cave near Carletonville he passed through the area and describes the natural springs coming out of the rocks, as well as the funnel shaped holes dotted all over the area. Being a former caver (in my younger years) I know that some of these lead to our biggest caves. In fact there is one with an entrance like this on the Gerhard Minnebron farm.
The Farm House
What is now the main house of the property was built by Gerhard, it is said in 1840. The yellow wood beams holding up the ceiling were imported from the Cape and brought in by ox wagon. The beams survived the fire which destroyed the top structure of the house during the Boer War. This time it is said the house was set alight by the Boers, because it was used by the British to store animal feed.
The house belonged to a British subject and was thus given priority and was restored very soon after the end of hostilities in 1902. The corrugated iron sheeting of the roof came from England as can be seen from the stamp on the sheeting. But the weather side is hidden now by a new roof of Harvey tiles put on top of the old roof. What is amazing is that the sheeting has lasted for more than 100 years now, I could only inspect it from the underside and could see no place where it had corroded.
Whilst crawling around under the roof I could also see the at places exposed wall bricks. Those were sun burned mud bricks which is what was available to the early Voortrekkers.
Sammy Marks and the irrigation channel
And then came Sammy Marks, the pioneer of industrialisation of the Transvaal. Also check the Sammy Marks museum amongst these pages. He bought the farm in the 1890s and was responsible for the first irrigation channel that captured the water direct from the fountain and led it to the irrigation fields. Part of that channel can still be seen at the dam wall now under water.
Interesting is that he used a contractor, Pieter Bezuidenhout, to build the capture wall and the irrigation channel. This is the same Pieter Bezuidenhout that started the 1st Boer War when he had his wagon confiscated by the sheriff in lieu of unpaid taxes in Potchefstroom.
The picture on the left (dated Feb 2016) shows the Bezuidenhout channel on the right side of the picture. That was the channel build by Bezuidenhout in the 1890's. It is not in use, hardly visible and totally overgrown. From the eye for about 100m it was concrete and then earth. On the left side is the channel presently in use. It was constructed by water affairs in 1962, it's a concrete channel.
A delightful story around this new channel. On Google Earth one can see that the channel has a bid of an unnatural kink not far from the dam. This came about because the channel was supposed to have passed through an ancient (Voortrekker times) stand of Pear trees. Mrs Coulter didn't like this and put herself between the construction team and her Pear trees. It worked, the engineer in charge decided to deviate from the plan and constructed the channel around the trees. Certainly an example of early environmentalism. Unfortunately the trees eventually succumbed to a fire and are no more
Radioactive pollution
There was a big stink a while ago when Uranium was detected in the Wonderfonteinspruit, that is the stream into which Gerhard Minnebron (GMB) water discharges its water, that was in 2008. And, of course, at times when things like this happen there will be sensational reporting like in this
article. Fortunately one finds more balanced facts and figures in this report by Frank Winde. And also in here by the same author. There are lots more references to this problem on the internet
It is noted that the water coming from GMB also showed an increase in concentration from average 0.5 μg/l, that is micro gram per liter or in other terms ppb (parts per billion) to 2.3 ppb. At the same time concentrations of up to 79 ppb were measured in the Wonderfontein Spruit. The subject is very complex because it is not known whether there is a connection between the water from the Wonderfontein Spruit through to the GMB. A hypothesis is proposed in Frank Winde's reports but nothing is certain. My hypothesis is that the increase in concentration at GMB is due to diffusion from the Wonderfontein spruit. Still, I will keep on swimming in the lake.
References
Emil Holub "Sieben Jahre in Süd-Afrika", subtitle: "Erlebnisse, Forschungen und Jagden auf meinen Reisen von den Diamantenfeldern zum Zambesi (1872-1879)", printed Wien 1881.