The plans of 1823, 1865 and 1893 show that there was a large pond near the centre of Katowice. But why was it there?
It appears that the pond was being used to supply water for Huta Marta - an iron works - from around 1852 coming from the Rawa River that runs through the centre of Katowice. But, the pond is actually a lot older as there are records showing that it also supplied a Blacksmith's Forge going back to 1397. It also appears on maps in the 17th and 18th century.
It would have served a dual purpose. It's likely to have been a fish pond supplying fresh fish for a Friday meal when Catholics don't eat meat. Water flowing out along the artificial canal or "leat" would have powered a waterwheel to drive bellows make the forge hotter for the Blacksmith whilst making iron tools for working on the land.
Later the waterwheel would have supplied power for the Huta Marta Iron works that operated from 1852 till 1928. Around 1858 the mill appeared to have employed 80 men, 92 women and a group of children. It was making rails. In 1892, the mill appeared to have thirty furnaces. In place of Iron works, "Marta" is now a block of flats Superjednostka (locally known as the Anthill) built in the 1960s.
The pond appears to be west of the present day Superjednostka (Anthill) block of flats and north of the Supersam shopping centre - but it has been gradually filled in since the 1823 map. Water would have flowed in from the west and out through two outlets back to the Rawa. Today, the Rawa has been canalised but can be seen to the west and east of Sokolska Street, before being covered to the north of Supersam. The line of the river has recently been exposed with the reconstruction of Rynek (Market Place) before it becomes fully opened again as a canalised route east of aleja Korfantego street.
Interestingly, an early 20th century photograph of the Rawa river shows it having a lot more water than it currently does. In fact in 1990 when a survey was done, it was found that the river has a "water deficit" - meaning that less water left the river than went into the river. It is likely to be due to "water leakage" - loss of water into the underground mines in the area.