Munich sewer system
The Munich sewer system is the sewage system in Munich.It comprises a 2,400 kilometer sewer network (in addition there are around 4,000 kilometers of connecting sewers for private households), has a possible storage volume of 700,000 cubic meters in 13 collecting basins and transports 560,000 cubic meters of sewage daily . In total, around 1.8 million people feed their wastewater into the network.
history
Before 1900
In 1811 the sewer was built from the Promenadeplatz to the Hofgraben. In the next few years approx. 21 km more canals were unsystematically built. However, the majority of faeces and rubbish was still simply disposed of on the street or in toilets.
In 1836, the doctor and hygienist Max von Pettenkofer recognized the cause of the recurring epidemics (especially cholera ) in the poor water supply and disposal of the citizens of Munich. His attempts to set up a systemic water supply and sewage disposal failed due to lack of money and disinterest in politics. It was not until the cholera epidemic of 1854, which cost the lives of 3,000 Munich citizens (including the Bavarian Queen Therese as the most prominent victim ), that people rethought. Until then, the city of Munich, which had grown to 130,000 residents within a short period of time, had been supplying its citizens with pump wells whose water quality was severely impaired by the sewage in the soil. Pettenkofer managed to get the government of Upper Bavaria to commission the Munich city council to expand the canal system.
The civil engineer and later town planner Arnold Zenetti planned the construction and was responsible for the implementation of the first sewer system in Schönfeld, Max and Ludwigsvorstadt (construction period 1862 to 1887). He was sent to Hamburg to study the sewer network that already existed there. Back in Munich, he first built 25 canals in downtown Munich. British engineer James Gordon was hired to create a total drainage plan for Munich. Since Solln is about 90 meters higher in the south than Freimann in the north, the more cost-effective alluvial sewer system was introduced in Munich, where rainwater simply washes away the dirt.
In 1885, the first department for urban drainage was established in the Munich city administration. In the beginning, sewer cleaning was particularly important, as residents kept complaining about the unpleasant smell. In 1899 the alluvial sewer system was introduced, which led to the establishment of the flush toilet in Munich.
From 1900
The Munich sewer network has been steadily and systematically expanded. At the turn of the century it had grown to 225 kilometers. Around 78 percent of the 480,000 inhabitants at the time were connected to the sewer system. As a result of the improvement in the hygienic situation, mortality fell significantly from 41.7 people per 1000 inhabitants in 1879 to 15.6 people per 1000 inhabitants in 1910.
All sewage from the city was directed north and ended up untreated in the Isar. All the dirt flowed past Freising and Landshut, which naturally provoked angry protests there. In 1926 the first Munich sewage treatment plant Gut Großlappen went into operation. In the decades that followed, the sewer network was systematically expanded and the amount of wastewater continued to increase. In 1989 the second Munich sewage treatment plant Gut Marienhof was put into operation. In 1998 a sewage sludge incineration plant went into operation at the Gut Großlappen sewage treatment plant .
Since 2006, practically all Munich citizens and businesses (99.9 percent) have been connected to the 2,400 km long wastewater disposal system.
description
Munich city drainage is responsible for the planning, construction and operation of the systems . This also offers tours through the canal system.
channels
The canal network runs from south to north, making use of the natural gradient. The ducts have dimensions from 25 cm for the smallest to 3.50 m wide × 5.20 m high for the largest. Sixty percent are accessible, the rest are pipes. There are 35,000 entries.
Rain retention systems
In Munich there is around 1000 mm of precipitation per year, which is the highest value of all major German cities. In the event of very heavy rainfall, the canals and the two sewage treatment plants are overloaded despite the double design. In order to ensure reliable drainage of the wastewater, which has been heavily diluted by the rain, there are currently 23 rain outlets in the urban area that lead from the sewer network directly into the Isar .
Since 1979 there has been a legal requirement that 90 percent of the degradable pollutants must be passed through a sewage treatment plant. In order to meet this requirement, large amounts of precipitation are temporarily stored in underground rain retention and rain overflow basins and, when the precipitation drops, fed to the sewage treatment works in a controlled manner. Even with very heavy rainfall, the discharge of mixed water into the Isar is largely avoided. When there is heavy rainfall, the mixed water from the sewer is channeled through a concrete partition wall into the underground structures, which consist of several sub-basins. If a partial basin is filled, the water continues to run into the next basin. In the case of the two-storey rain retention basin under the Hirschgarten , the lower basins are filled via fall shafts. The upper basins are emptied by opening a valve, the lower basins by pumping stations. The mixed water is fed back into the municipal sewer network through a drainage channel and is therefore returned to the sewage treatment plant.
Munich municipal drainage operates a total of 13 rain retention systems with a total volume of 706,000 cubic meters. To illustrate: this corresponds roughly to the amount of water with which the playing field of the Allianz Arena could be flooded 100 meters high.
Wastewater treatment
The waste water is in the two treatment plants Good Großlappen and Gut Marienhof purified and is used for secondary clarification of good Großlappen out in the fish ponds on Ismaninger reservoir and to a lesser extent in the reservoir itself and of good Marienhof from about the mid-Isar-channel in the Isar headed.
Others
Stadtentwässerung München has a training channel in its sewer operations station at Schleißheimer Straße 387A . Here employees can abseil and practice cleaning in a replica 1.50 meter high canal.
The Munich sewer system was, among other things, the location for Tatort , Schimanski and notes from the provinces .
See also
Individual evidence
- ↑ a b 17 steps into the Munich underground. In: sueddeutsche.de . March 23, 2018, accessed October 13, 2018 .
- ↑ Our leisure tip: One floor down - guided tour through the Munich sewer system | münchen.tv , October 12, 2017
- ↑ Guided tour through the sewer system - Munich from below - District of Munich - Süddeutsche.de , March 14, 2011
- ↑ Melanie Staudinger: This is how Munich's underground is kept in good shape. In: sueddeutsche.de . May 4, 2018, accessed October 13, 2018 .