Most towns augment their water supply from wells, and in South Africa, where the rivers are said to run underground, Johannesburg is no exception.

Its chief supply is from deep wells in the dolomite some 20 miles to the south-west of the town, but one of the suburbs—Parktown—is not connected to the main supply, but at present draws its water from two wells (the property of the Rand Water Board) which will be subsequently referred to as No. 1 and No. 2, sunk in the shales of the upper Witwatersrand beds. From here the water is pumped to two Water Towers situated at the highest point of the suburb from whence it is distributed by gravitation. For various reasons, the Rand Water Board had decided on replacing the pumping machinery at these wells by electrically driven gear, and advantage was to be taken of the change to properly line and deepen the wells by a steel bore-hole.