Mining and hydrological transformations in Upper Silesia from the fifteenth to the nineteenth century

This paper analyses the influence of mining on hydrological conditions in U pper Silesia from the fifteenth to the nineteenth centuries. The perturbati on of local hydrological conditions began in the fifteenth century as a res ult of wide-scale mining of iron, silver and lead ores. Further changes too k place during the sixteenth and seventeenth centuries, following the appli cation of gravitational mine drainage. As a result, a compact cone of depre ssion, covering an area of about three square kilometres was created. In th e eighteenth century, the activities of mills, sawmills and smelters caused considerable changes in the surface river network and created the so-calle d anthropogenic Upper Silesian Lakeland. At the end of the eighteenth centu ry, underground mining activity was renewed and as a result the area of the compact cone of depression increased to ten square kilometres and its dept h reached 50 metres.