Characteristics and location
Roter Graben is an artificial ditch built in the 17th century. Running along the foot of the Davidschacht Tailing, Roter Graben drains the Freiberg mining area. It runs between Halsbach and Halsbrücke, largely parallel to the Freiberger Mulde River.
As a branch from the ditch of the middle Ratsmühle northern from Halsbach, the water from the Freiberger Mulde River supplies the Roter Graben. Running on the west side of the Freiberger Mulde River, it passes the mouth of the Königlich Verträglicher Gesellschaftsstolln to the north. From this tunnel, it takes in draining pit water. Roter Graben continues to pass through the mouth of the Thurmhof Hilfsstolln and the main break in the old Tiefen Fürstenstolln and in turn absorbs its pit water.
It runs to the Freiberger Mulde River through several surcharges. The name refers to red, iron-rich precipitates in the ditch. Roter Graben is currently heavily silted.
Roter Graben contains approx. 13,000 m3 of ferrous mud. Since the ditch is leaky, there is a risk of heavy metal pollution for the groundwater. The ditch also endangers surface water if it should overflow. If Freiberger Mulde River floods, there is a risk that ditch sediments will be mobilized and retaining walls will be torn away. Thus, Roter Graben endangers the soils on the banks of the Freiberger Mulde River during floods.
Objects of investigation
- Fe- and Al-rich, hydroxydic mud
- Mine waters
One of the best-known artificial ditches in the Freiberg district, the Roter Graben, leads from Halsbach to Halsbrücke and on to the Churprinz mine. The ditch was built between 1614 and 1615 and passes important tunnel mouth holes emerging in the valley of the Freiberger Mulde River. Roter Graben supplied the impact water for the artifacts and water gobs of the St. Johannes and St. Lorenz pits on the Halsbrücker Spat. Roter Graben later supplied some of the energy required for the smelter in Halsbrücke.
Nowadays, the water-bearing ditch has various cuts into the Freiberger Mulde River over a section of the route, some of which are stabilized by considerable slope retaining walls. In the area of Halsbrücke, Roter Graben has partially disappeared.
Since the route from the Roter Graben in Halsbrücke corresponds to the route from the Bergmannsweg, it is a popular hiking trail today.
The Roter Graben is a UNESCO World Heritage Site since 2019.
Current projects at Roter Graben
- Project ZauBer: "Future materials from mining sludge" as part of the funding measure "recomine - resource-oriented environmental technologies for the 21st century", project coordination: Institute for Technical Chemistry, TUBAF Freiberg, est. 2021-2023
Phone: +49 351 260 4417