Am Staad waterworks
The Am Staad waterworks is the third of four waterworks in the Düsseldorf area. It is located in the north of Düsseldorf . It is operated by Stadtwerke Düsseldorf . At the Staad, 20,578,000 m³ of drinking water are treated every year (as of 1998).
history
The limits of water pumping in Düsseldorf were reached in 1925 at the Flehe waterworks (the first Düsseldorf waterworks): when the water levels were low, the plant could no longer supply enough water. This is how the Am Staad waterworks was built between the Schnellenburg and the old northern border between 1928 and 1931.
Extensive hydrological investigations had shown that Am Staad not only had excellent water - water-bearing layers are up to 24 meters thick here - but that the plant was also conveniently located for the delivery area. 25 filter tube wells were sunk on 500 m of the Rhine front - daily output 65,000 cubic meters of water. Two electric centrifugal pumps, each with 360 HP , delivered it. The cost was 5.3 million marks.
A new construction method - the chemical petrification process used for the first time in Germany - had the advantage that the productivity of the water catchment did not decrease even if the groundwater level fell deeper. This also explains the small number of wells. According to the old technology, 60 wells would have to be drilled for the same daily output. Whitsun 1931, the first liters of drinking water flowed from the peak demand system. In 1929 Kaiserswerth was incorporated, so that from 1933 the water was supplied from Am Staad via a 300 mm wide pipeline, the local waterworks became superfluous.
During the Second World War , the plants in Flehe and Am Staad were badly affected. Most of the pumping station building on the Staad collapsed, the machinery was unusable due to a direct hit and the switching station was almost completely destroyed. The drainage pumps had failed, the pump shaft filled with water. The access house and the ventilation house to the siphon canal were completely destroyed. The siphon pipe itself was torn apart by blast waves and was leaking in many places. The temporary electrical switching station of the emergency waterworks had also been hit. The plant had to stop operating. At the end of 1945 the machine house and switch house were completely renewed and operations resumed.
The pumping station 1 consists of 20 individual vertical wells which are connected to one another via a siphon pipe. In 1954 pumping station 2 was put into operation, followed by pumping station 3 and 4 in 1960 and 1969. These pumping stations are all built as horizontal filter wells. A total of five more wells were added by 1973. There are a total of 10 pumps on the site of the Am Staad waterworks.
From October 1958, for the first time, the entire delivery volume of the Staad works group was "treated" with chlorine dioxide , made from sodium chlorite and chlorine . Although the process was not sufficient to improve the smell and taste, it proved to be more useful for the safety chlorination, which is necessary to keep the water in the pipe network sterile.
When the “economic miracle” began, the obligation to always supply impeccable drinking water posed problems for Stadtwerke Düsseldorf after a short time. Due to the water seeping into the gravel and sands of the floodplain, the quality of the water in the wells deteriorated rapidly with the increasing pollution of the Rhine from 1949/50. However, as analyzes from 1961 show, the well water always differed greatly from the Rhine water - thanks to the excellent natural filtering in the soil. As early as the twenties and thirties, increasing wastewater pollution of the Rhine and a gradually rising chloride content had been ascertained. Nevertheless, the well water remained drinkable without any treatment. Then the smell and taste of the water increasingly deteriorated. Industrial plants and cities led more and more wastewater into the Rhine. Of all the water treatment methods tested, the one with activated carbon and ozone worked best. Since the Am Staad waterworks pumped the poorest quality well water in Düsseldorf, the Stadtwerke there, after many years of testing, laid the foundation stone for the first treatment plant based on the Düsseldorf method. It was put into operation in 1961 and delivered 6000 m³ of drinking water "treated" with ozone and activated carbon every hour .
In November 1986, after the fire in the Basel chemical company Sandoz , the Flehe and Am Staad waterworks were temporarily shut down to protect the groundwater due to the population's fear of poisoned Rhine water. Strict checks of the groundwater and well water over several weeks by several scientific institutes finally showed that neither groundwater nor well water was damaged.
In 1993, extensive construction and renovation work was carried out at the Am Staad waterworks. New water rights of 15 million cubic meters per year until 2027 for Flehe and of 22.5 million cubic meters per year until 2028 for the Am Staad waterworks have been granted. In 2003 the new control room in the Am Staad waterworks was put into operation. All extraction and processing processes are controlled with a click of the mouse.
processing
The first stage is bank filtration. The second stage is oxidation by ozone : 0.5 g / m³, ozone generation from oxygen. Step three: pre-activation by means of activated carbon filtration in a closed construction, grain size: 1.5 - 2.5 mm, area: 20 m², height: 1.5 m, throughput: 200 m³ / h. Stage four is activated carbon filtration in a closed construction, grain size: 0.8 - 2.4 mm, area: 20 m², height: 2.5 m, throughput: 200 m³ / h. (Formerly level 5: disinfection with chlorine dioxide : 0.05 g / m³.) And finally, level five: Inhibitors with phosphate : 1 g / m³ (previously also with silicate: 1 g / m³.) (As of 2016).
Coverage area
The drinking water supply area of the Düsseldorf waterworks comprises 600,000 people, trade and industry in Düsseldorf, Erkrath and Mettmann . In total, around 50 million cubic meters (m³) of drinking water are distributed in one year, which is an average of 140,000 cubic meters - 140 million liters per day. The daily charge varies between 120,000 cubic meters in winter and up to 250,000 cubic meters on a hot summer day.
biodiversity
The waterworks site ( water protection zone I + II) has always been used extensively ; it is not fertilized or treated with pesticides.
Area limitation: The biodiversity relevant areas extend as:
| Meadow area Vordeich left (fountain gallery) | 0.81 ha |
| Meadow area Vordeich right (fountain gallery) | 3.30 ha |
| Meadow area pumping station 3 and 4 | 3.21 ha |
| Meadow area inside | 4.00 hectares |
The dike is exposed to the southwest (areas 4 and 5 in the picture on the right). It is flat in the lower section towards the Rhine, the location is relatively nutrient-rich and fresh. The partial area 4 is steeply inclined and dry in the middle section of the dike. The upper section is flatter again. The surface 5 is slightly inclined in the middle section and strongly inclined in the upper section.
70 plant species, including 18 characteristic species of the Stromtal semi- arid grassland, were recorded on these areas . With 50 species in area 4 and 55 species in area 5, this dike is also very species-rich. The partially dominant occurrence of the shaggy rattle pot (Rhinanthus alectorolophus) is significant . This species is endangered in NRW ( Red List 2 ) and threatened with extinction in the Lower Rhine Bay (Red List 1). The western section of the dike is built up in several stages. In the upper slope area, plants of the semi-arid grassland can often be found, e.g. B. Erect brome (Bromus erectus). In the upper level grows Holcus mollis (Holcus lanataus), Small burnet (Sanguisorba minor), Common Rumex obtusifolius (Rumex obtusifolia), Marsh knapweed (Centaurea scabiosa) and daisy (Chrysanthemum leucanthemum). The intermediate level is characterized by the small meadow button (Sanguisorba minor) and the shaggy rattle pot (Rhinanthus alectorolophus). Smooth oats and golden oats grow in the lower area .
The meadow at the pumping station (area 6 in the picture on the right) has high, but in many places gaps in vegetation. This poor oat meadow is rich in species with 39 species. Here, too, the shaggy rattlespot (Rhinanthus alectorolophus) occurs regularly. Other conspicuous species of the lean meadows are the scabious knapweed (Centaurea scabiosa) and the field scabious (Knautia arvensis). The frequent occurrence of the comb grass (Cynosurus cristatus) is remarkable . Jacob's ragwort (Senecio jacobaea) spreads particularly in the northern section , which is a great danger to livestock, as the hay is used as animal feed.
A total of 107 plant species were recorded on all investigated areas. These include 13 species on the red list and 5 on the warning list.
On the dyke areas of the waterworks, the Stromtal semi-arid grassland, the relics of the sage meadows, could be preserved due to the extensive use over many years. Only a few of the species characteristic of this plant community were not found. The meadow areas are very species-rich and worth protecting.
Stromtal semi-arid grasslands are severely endangered according to the Red List of Plant Societies in North Rhine-Westphalia. They are also an FFH habitat type and a legally protected biotope type according to Section 62 of the North Rhine-Westphalia Landscape Act. This meadow community needs full tanning and two-tier mowing without fertilization. Through the drying of the mowing and the omission of the seeds in the meadows, as well as the subsequent removal of the hay, nutrients are removed. The species-rich Flehe site was able to develop over a period of 50 to 60 years.
Since a cooperation contract with the Biological Station Haus Bürgel in 2010, the meadows have been scientifically monitored. A floristic survey took place in 2010, a locust survey in 2012.
There is also a transfer of cuttings and thus seeds for the new planting of grassland.
literature
- The city of Düsseldorf's new waterworks “am Staad” / by A. Lang. - from: "Das Gas- und Wasserfach", 1930, booklets 2,3,4
Web links
- From raindrops to the tap
- Drinking water treatment & supply
- Current drinking water analysis by Stadtwerke Düsseldorf
- Formation and disappearance of the sage meadows on the Lower Rhine. By Karl-Heinz Knörzer
- Dealing with the Jacob's ragwort, avoiding, tolerating, fighting. From Dr. H. Neumann et al.
- Water management companies - active for biodiversity, options for action and good examples
Individual evidence
- ↑ a b Rüdiger Furrer, Michael Fleig and Heinz-Jürgen Brauch: Water pumping and treatment in the Rhine catchment area - IAWR. (PDF; 2.7 MB) (No longer available online.) Archived from the original on March 11, 2014 ; accessed on March 11, 2014 . Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice.
- ^ Stadtwerke Düsseldorf: Düsseldorf drinking water treatment and supply. Retrieved September 26, 2016 .
- ↑ Stadtwerke Düsseldorf: Clearly drinking water - basic material of life. (PDF) Retrieved September 26, 2016 .
- ↑ Biological station Haus Bürgel: Floristic study of the meadows in the waterworks Flehe and Am Staad with care instructions. (PDF; 3 MB) Retrieved October 12, 2015 .
- ↑ Biological station Haus Bürgel: Spread of locusts on the meadows in the Am Staad and Flehe waterworks with care instructions. (PDF; 1 MB) Retrieved October 12, 2015 .
Coordinates: 51 ° 15 '36 " N , 6 ° 43' 36" E