Schwalm (Maas)

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Schwalm
The Schwalm between Hariksee and Borner See

The Schwalm between Hariksee and Borner See

Data
Water code EN : 284
location Germany

Netherlands

River system Rhine
Drain over Meuse  → Hollands Diep  → North Sea
River basin district Meuse
source in Erkelenz-Geneiken
51 ° 5 '52 "  N , 6 ° 15' 31"  E
Source height 85  m above sea level NHN
muzzle at Swalmen in the Meuse coordinates: 51 ° 14 ′ 56 "  N , 6 ° 0 ′ 35"  E 51 ° 14 ′ 56 "  N , 6 ° 0 ′ 35"  E
Mouth height approx.  12  m NAP
Height difference approx. 73 m
Bottom slope approx. 1.6 ‰
length 45.3 km
Catchment area 268.665 km²
Discharge at the national border level MQ
 1.6 m³ / s
Reservoirs flowed through Hariksee

The Schwalm ( Dutch Swalm ) is a 45.3 km long, southeastern and right tributary of the Maas in North Rhine-Westphalia ( Germany ) and in the Netherlands .

geography

course

The Schwalm spring

The Schwalm rises in the urban area of Erkelenz in the district of Geneiken . A few kilometers below its source, it flows through a wetland south of the Wegberger district of Tüschenbroich at about 85  m above sea level. NHN . From there, its water flows mainly through the Maas-Schwalm-Nette Nature Park , with its river bed running between Rur , Nette and Niers . It also flows through Wegberg, Lüttelforst , past Waldniel and Niederkrüchten , through the Hariksee , through Brüggen-Born , Brüggen and Swalmen . From the total length of the Schwalm to the confluence with the Meuse , near the town of Swalmen at about 12  m NAP , 13 kilometers run on Dutch territory.

Parts of the river course have a natural meander course .

Catchment area and tributaries

The catchment area of the Schwalm is around 268.665 km², of which around 27 km² are in the Netherlands. Its tributaries include:

nature and environment

Water quality

The water quality of the Schwalm could be improved by structural measures on sewage treatment plants . In 2001, the water in the Schwalm was mainly of biological quality class II or II-III.

Then the system of water quality description was changed within the framework of the Water Framework Directive .

Headwaters

The original source area has now become a swamp forest area and has become ailing : the water of the Schwalm comes mainly from the swamps (pumping out areas) of Rheinbraun .

The lignite mine is obliged Sümpfungswasser that otherwise the up to 230 m deep pits filled, feed it into the surface water. This is done with the help of slot shafts through which the water flows back to the groundwater. If these slot shafts did not exist, the Niers and Schwalm would have long since dried up. The alder-ash wet forests typical of the landscape would then also perish.

Flora and fauna

The moor forest and heather moor areas along the course of the Schwalm provide a diverse habitat for fauna and flora . Frogs , dragonflies , bluethroats , kingfisher and oriole can be found as well as water crowfoot , hail bush and other rare plants. In the water are brown trout , barbel and chub at home, in the shore area also various representatives of the family of coypus .

history

The Schwalm in front of Brüggen

The Schwalm's hydropower has been an important economic factor in the region since the 13th century. In the 20th century, the course of the Schwalm river was straightened in order to be able to better drain the adjacent meadows and fields. The lakes along the Schwalm were created through peat extraction, sand extraction or gravel extraction. The Schwalm's water pollution increased until the 1980s .

The region was a large flax-growing area for the textile industry . The flax seeds were ground in the numerous oil mills along the Schwalm. There were once over 20 mills along the 21 kilometers of the Schwalm from the source to Overhetfeld. Some of these mills still exist today as architectural monuments and / or are used as tourist restaurants . The oldest watermill along the Schwalm is the Mühlrath mill on the north bank of the Hariksee .

Since 1976 attempts have been made to restore the Schwalm and its lakes to a more pristine state ( the original state does not exist). People have been settling at the Schwalm for at least 1200 years and changing it permanently. The town of Brüggen was a border fortress between the duchies of Jülich and Geldern, the Schwalm formed the border, and its water was used to flood the moats and fortifications. No one knows what condition the river and river valley were in around 1200 when Brüggen Castle was completed; neither the climatic nor the hydrological conditions can be reconstructed even approximately reliably.

On an approximately three-kilometer stretch between Born and Brüggen , river loops with Werdern (= river islands) were created and polluted willows were planted.

At the Hariksee , through which the Schwalm flows, there are weekend houses in places. Along the banks of the Schwalm there are looped systems of the Siegfried Line , for example at Hariksee and near Born. Debris from the Siegfried Line bunkers that were blown up after the war are secondary biotopes for bats, for example.

Mills

Mühlrath mill

Mills on the Schwalm, there were a total of 25, are or were; other mills were located at tributaries:

Present and Future

The changes in the course of the river in the 1920s and 1930s, the so-called "amelioration" ("improvements" in the sense of amelioration ) have proven to be pointless, harmful and expensive. During this time, they wanted to turn the last piece of wet meadow into arable land. The Nazi regime did this excessively (in many places in Germany); also to increase Germany's self-sufficiency . The work was at the same time a job creation measure ; the Nazis wanted to get unemployed people into employment; the work could have been done cheaper with construction machinery.
When the Rhineland Regional Council presented a concept for the Maas-Schwalm-Nette nature park in 1976 , a lot changed, including for the Schwalm. The Schwalm low river, which flowed through over-fertilized cow meadows and also had to absorb the sewage from Waldniel and Wegberg , was to become a natural body of water again. This became the task of the Schwalm Association .

Cycle tourism has increased; the cycle path network has been expanded and better signposted.

The last sections of the Dülken – Brüggen railway (“Schwalmtal Railway”) - from Brüggen via Amern, Waldniel, Dülken (to Viersen and thus to the main Rheydt – Cologne-Ehrenfeld line ) were dismantled after 2004.

The changes made by humans in the past are partially reversed. In some sections, the formerly canalised river bed was converted into a meander course. The renaturation between Lake Borner near Brüggen-Born and about 1500 meters further west near Borner Mühle is worth seeing. Fish ladders have been built at the Mühlen dams .

In 2012 the first German-Dutch level measuring station was put into operation in the Schwalm between Brüggen and Swalmen . Your data should help water associations on the German side and in Venlo with water management.

literature

  • Horst Jungbluth, Helmuth Elsner: The Schwalm - valley of the mills . Schwalmtal, 1989
  • Helmuth Elsner: The Schwalm - history and stories of a 'hardworking' river - mill-rich river landscape in transition. Schwalmtal, 2016
  • Furnishing plan for the Maas-Schwalm-Nette Nature Park. Rheinland Verlag, Cologne, updated until 1994
  • Herbert Feilke: To Niers-Schwalm-Nette . Ziethen-Verlag, Cologne, 1984, ISBN 978-3929932485

Web links

Commons : Schwalm  - collection of images, videos and audio files

Individual evidence

  1. ^ German basic map 1: 5000
  2. ↑ a b c d Topographical Information Management, Cologne District Government, Department GEObasis NRW ( information )
  3. ↑ Maas river basin district / Schwalm sub-catchment area  ( page no longer available , search in web archives )  Info: The link was automatically marked as defective. Please check the link according to the instructions and then remove this notice.@1@ 2Template: Toter Link / daten.flussgebiete.nrw.de  
  4. ↑ LANUV : Water quality report ( Memento from August 8, 2014 in the Internet Archive )
  5. ↑ www.niers-schwalm.nrw.de
  6. ↑ Monitoring Garzweiler II - Annual Report 2018 (pdf), p. 6.
  7. ↑ LANUV (State Office for Nature, Environment and Consumer Protection North Rhine-Westphalia)
  8. ↑ Friedrich Wilhelm Dahmen was involved, see z. B. Contributions to regional development. 41 Schwalm-Nette Nature Park, balance sheet 1983 (Rheinland-Verlag; Bonn: Habelt, 1984)
  9. ↑ Niederrheinrad.de  ; www.niederrhein-tourismus.de
  10. ^ Rheinische Post online April 2, 2012