Waterworks at the Hochablass
The waterworks on the Hochablass , also known as the drinking waterworks on the Neubach , is the first waterworks built in Augsburg for the conveyance and treatment of drinking water . At that time it formed the cornerstone for a modern, hygienic central drinking water supply in the Augsburg city area. After it was closed in 2007, it is used by the Augsburg public utilities as a hydropower station for generating electricity, a technology museum and an information center for Augsburg's drinking water supply.
The waterworks at Hochablass is part of Augsburg's historical water management . On January 15, 2015, it was nominated for the UNESCO World Heritage List .
history
In his function, the waterworks at Hochablass replaced the waterworks at Red Gate . Before 1871, most households supplied themselves with drinking water from public wells, only a few households were connected to the urban pipe network, which, however, was also fed by wells in the built-up urban area.
The poor drinking water quality and cholera epidemics drew attention to the forest areas close to cities for the production of clean drinking water. In 1876 the magistrate decided to build a waterworks at the Hochablass weir and to build collecting wells in the neighboring Siebentischwald . The proximity to the Lech and the high drainage weir was chosen to be able to drive the pumps required for conveying by means of water power. In the same year the construction of the plant began, at the same time the pipe network in the city area was renewed and expanded for a comprehensive water supply. In the spring of 1878, the construction work for the headrace channel , the so-called Neubach , was finished. The building above the Neubach could now be erected. Built in the late classicist style, the machine hall spans the Neubach like a yoke, two towers adorn the west facade, the technical equipment was supplied by the Augsburg machine works , the predecessor of today's MAN. In addition, service apartments were built for the shift staff.
The waterworks officially went into operation on October 1st. Three Henschel-Johnval turbines drove three double piston pumps via a common shaft , the so-called " vertical shaft". The power transmission between the turbine, vertical shaft and the pumps was realized with wooden gears . Overall, the technical equipment of the waterworks was considered a sensation at the time and caused a sensation across Europe. Each of the three installed pumps was designed as a double piston pump with small pressure air tanks. The pistons worked in opposite directions, while one piston was pushing the water into the line, the other piston was already sucking in fresh water. This, together with the small pressure air vessels, prevented pulsating line pressure. An elevated tank could even be dispensed with entirely. The extracted drinking water was pumped into four large, 10-meter high pressure air vessels before it was fed into the pipe network. In them, the air was compressed by the water until a constant line pressure of 5 bar was reached.
The four large air pressure vessels in the north tower
Bottom view
The waterworks soon got the nickname "Temple of Technology" because of its architecture and technical performance. The colorful wall paintings and the terrazzo floor inside the machine hall still bear witness to the vital importance of water. In 1885, just a few months after commissioning, the waterworks was expanded to include a boiler house with a steam engine as an emergency unit, in order to maintain the drinking water supply even when the water level was low and the turbine output decreased. Because of the fire hazard posed by the steam engine, the boiler house was not attached to the pump house, but was built at a distance behind it. Soon after the flood disaster in 1910 , the waterworks had to prove its technical capabilities. A tidal wave as a result of heavy snowmelt, triggered by heavy rainfall in the summer in the Alps, destroyed the high drain weir and the neighboring restaurant. As a result of the destruction, the inflow of the Neubach was almost drained, causing the turbines to fail and the pumps could no longer be powered by water power. For several months the steam engine took over the drive of the pumps and kept the city water supply up. After the weir systems had been rebuilt, it was decided to replace the Henschel-Jonval turbines with more powerful Francis shaft turbines . The new weir system and the rebuilt high drain restaurant also brought some innovations, such as electrical lighting and lock control. For this purpose, a generator to generate electricity was installed in the waterworks in 1911 and connected to the vertical shaft by means of transmissions and leather straps.
From 1912 the Hochablass waterworks grew, followed by the construction of the waterworks on Lochbach and further systems followed. The flood disaster had shown how vulnerable a single waterworks directly to the river can be. From then on, people no longer wanted to be dependent on a single waterworks in an emergency or a crisis. In 1935 the steam engine emergency unit was replaced by a MAN diesel engine, the chimney was torn down, the boiler was dismantled and the gap between the building and the machine shop was closed. The diesel engine found its place in the superstructure and was coupled to the vertical shaft there. Constant expansion of the pipe network and the expansion of wells resulted in higher production rates. Technical progress did not stop at the waterworks either, new technology moved in and a new era began. In 1942 the first two electric centrifugal pumps for pumping drinking water were installed in the cellar under the machine hall . From now on, water was pumped electrically and with hydropower. Around 1948 the piston pumps finally reached their capacity limits. Due to the expansion of the water supply in the Meringerau, the waterworks is getting an additional supply line to its suction basins. The three piston pumps can no longer cope with these additional capacities, another three electric centrifugal pumps are installed and do their job from 1950. With the construction of a new waterworks in Meringerau in 1961, the situation changes. Capacities were lost, the more powerful centrifugal pumps now almost entirely took over the task of pumping drinking water. The water-powered piston pumps no longer play the main role.
Outer facade, the former control center was housed in the front tower.
Entrance portal
Entrance portal detail
Back of the building with inlet of the new brook
Shutdown
After 94 years of operation, the turbines and piston pumps were shut down on December 3, 1973, and the water supply from the Neubach to the turbines was sealed off and filled in. Since then, the water supply has only been electrical, and the centrifugal pumps also generate the line pressure directly. In 1975, the waterworks monitoring and control was switched to remote operation, and the company apartments that were no longer needed were demolished. Until the conversion to remote operation, a control center was housed in the right tower , the function of which has now been taken over by the Stadtwerke headquarters in the Stadtwerkehaus. Since then, all other municipal waterworks have also been monitored and controlled from there. The neighboring Hochablass restaurant was demolished in 1979 because of a feared danger to drinking water . Your former roof tower now stands as a pavilion at the weir entrance.
Restoration and technology museum
By 1980 the waterworks was no longer showing its best side. The several decades of operation and the effects of the weather took a toll on the building. Restoration and renovation began in 1986 . The first steps were a roof renewal and the renovation of the outer facade in the original color of 1879. In the following years, an information center for drinking water production was set up in the former control center and officially opened to visitors in 1989. The interior of the machine shop was still in a desolate condition. Parts of the terrazzo floor were missing, the walls were a faded gray-green paint. In 1990 restorers procured replacement material for the floor and began restoring it. During the subsequent painting work, the old and once colorful decorative paintings were rediscovered by chance among the later paintings. Apparently they had been forgotten a few decades ago and were carelessly painted over. The murals were uncovered between 1991 and 1993, and restoration work began in the summer of 1993. A short time later in 1994, the pump house was presented to the public again in its old glory on the day of the open monument .
Recommissioning to generate electricity
As early as 1981, the proposal was made to use the old turbines to generate electricity as before. In 1991, Stadtwerke Augsburg began to expand and overhaul the turbines as part of the building renovation. The water inlet of the new brook was restored and new automatic weir systems were installed to regulate the water inlet. In 1993 the Francis shaft turbines built in 1910 were put back into operation. A modern three-phase generator with transmission gearbox and 250 kilowatts of power was coupled to the vertical shaft to generate electricity . The transmission gear provided the necessary higher speed that the generator needed to generate electricity. The generator was set up between the emergency diesel engine and the pump house. In 1999 the Augsburg water supply celebrated its 120th anniversary, and drinking water continued to be supplied electrically with the centrifugal pumps installed in the basement from 1942.
Final decommissioning and conversion to a hydropower plant
In the following years from 2000 it became increasingly clear that the three Francis turbines had soon completed their service life. The ravages of time had affected them, which resulted in a shortening of the maintenance intervals and thus increased the number of necessary maintenance work. Therefore, it was decided in winter 2005 to replace the Francis shaft turbines with more modern and more powerful Kaplan S turbines , each with a connected generator . In total, they deliver a fifth more power than the old turbines, which means that even the water works' own electrical energy requirements for drinking water generation can be covered. From then on, the excess electricity generated was fed into the public grid . The high drainage weir had to prove its stability again during the floods in summer 2005 . Fortunately, there was no destruction like in 1910.
New well technology soon heralded the end of drinking water pumping in the waterworks built in 1878. Modern submersible pumps in the filter wells already provide the necessary line pressure, which means there is no need for a pumping station. Therefore, from 2006 a new waterworks (a so-called water transfer point) with filter systems, an emergency UV disinfection system and a measuring point for drinking water quality control was built opposite the old waterworks and put into operation in 2007. From now on it replaced the old waterworks, the drinking water supply was stopped and the electric centrifugal pumps finally shut down. In contrast, the Kaplan S turbines installed two years ago have remained in operation and have been generating electricity for 2,300 private individuals since then. The transition from the waterworks to the hydropower plant was completed.
A model of one of the Kaplan S turbines installed in 2005, front view
Rear view, view of the impeller and the mechanism for adjusting the guide vanes
Technology museum and drinking water information center
Regular guided tours are offered by the Augsburg public utilities. Interested parties can choose a given date and register on the Stadtwerke Augsburg website. In addition, the waterworks is open to the public at certain events, such as the open house or water day, etc. and can be visited without registration. To give an impression of the drinking water pumping with the old double piston pumps, one pump is set in motion by an electric motor together with the emergency diesel engine and the vertical shaft . Display boards explain the overall function of the old waterworks, the centrifugal pumps set up in the basement can also be viewed along with other utensils for pumping drinking water. In the former boiler house there is a permanent photo exhibition with historical photos of the waterworks and the high drain weir . A Francis shaft turbine preserved in a museum is exhibited on the open-air site.
Individual evidence
- ^ Hydraulic Engineering and Hydropower, Drinking Water and Decorative Fountains in Augsburg. In: whc.unesco.org. UNESCO World Heritage Center, accessed May 22, 2018 .
- ^ Stadtwerke Augsburg: private customers
- ^ Augsburger Allgemeine: Visit to the historic waterworks on April 9, 2013
literature
- Franz Häußler: Augsburg's historic waterworks. A unique technology museum. context Verlag Augsburg, Augsburg 2010, ISBN 978-3-939645-33-7
- Martin Kluger : Augsburg's historical water management. The way to the UNESCO World Heritage. 1st edition, context Verlag, Augsburg 2015, ISBN 978-3-939645-81-8
Web links
- Article on the flood disaster of 1910 in the Aichacher Zeitung
- Water transfer point at the Hochablass
- Item Description: Augsburgs historisches Wasserwerk
- Virtual tour
Coordinates: 48 ° 20 ′ 50.9 ″ N , 10 ° 56 ′ 6 ″ E