Werre

from Wikipedia, the free encyclopedia
Werre
Course of the Werre

Course of the Werre

Data
Water code EN : 46
location North Rhine-Westphalia ( Germany )
River system Weser
Drain over Weser  → North Sea
source In Horn-Bad Meinberg / Wehren
51 ° 54 ′ 39 ″  N , 8 ° 59 ′ 31 ″  E
Source height 247  m above sea level NHN
muzzle Near Bad Oeynhausen - Rehme in the Weser Coordinates: 52 ° 13 ′ 16 ″  N , 8 ° 49 ′ 40 ″  E 52 ° 13 ′ 16 ″  N , 8 ° 49 ′ 40 ″  E
Mouth height 42  m above sea level NHN
Height difference 205 m
Bottom slope 2.9 ‰
length 71.9 km
Catchment area 1,485.398 km²
Discharge at the Löhne
A Eo gauge: 1,335.11 km²
Location: 10.29 km above the estuary
NNQ (01.09.2009)
MNQ 1983/2014
MQ 1983/2014
Mq 1983/2014
MHQ 1983/2014
HHQ (31.12.1986)
2.9 m³ / s
4.48 m³ / s
17.5 m³ / s
13.1 l / (s km²)
178 m³ / s
340 m³ / s
Left tributaries Bonebach , Rethlager Bach , Haferbach , Aa , Bentgraben , Heipker Bach , Siekbach , Düsedieksbach , Rehmerloh-Mennighüffer Mühlenbach , Else , Kaarbach
Right tributaries Bega , Bramschebach , Haubach , Mittelbach
Medium-sized cities Detmold , location , Bad Salzuflen , Herford , Löhne , Bad Oeynhausen ,
Small towns Horn-Bad Meinberg
Communities Leopoldshöhe , Hiddenhausen , Kirchlengern
Residents in the catchment area 870,000 inhabitants

The Werre ( Low German de Weern ) is a left tributary of the Weser in the northeast of the German state of North Rhine-Westphalia .

The Werre rises in the western Lipper Bergland near Horn-Bad Meinberg and drains large parts of the Ravensberger Mulde between the Wiehen Mountains and the Teutoburg Forest . At Bad Oeynhausen it flows into the Weser at the Great Weserbogen . The largest tributaries of the Werre are the Bega , Aa and Else .

The Werre, which flows exclusively in the Ostwestfalen-Lippe region, has a length of 71.9 km. Measured by its length and water flow , the Werre is the second largest tributary of the Upper Weser after the Diemel .

Surname

The Werre was first mentioned in a document in 784 in the Frankish imperial annals "ad locum ... in quo Wisura et Waharna confluunt" as Waharna in the context of Charlemagne's Saxon Wars . In the year 785 also "... ubi confluit Waharna". The documented Uuerna appears for the year 868 and a Warnae appears in the Poeta Saxo in the same century . In the 13th century the document Werna appears ("in utroque flumine tam in Hartna quam Werna"); End of the 14th century, that means for the year 1399 in Middle Low German form bi der Werne , finally for the year 1721 the Wehrde , Were .

The starting form for today's name is the old Saxon * Werina zu Varna . Etymologically is probably a Suffixableitung -ina of Germanic * was- from protogermanisch * uor- , deriving the Indo-European root * h 2 uer- meaning for "moist (to be)" back. The oldest document form Waharna is a copulative compound from * Warnahardna , especially for the lower reaches where the Aa flows into the Werre from Herford. In addition to the current name of the Aa, another medieval name for the water is known as the Hartna ; hence the declaration of the Varna-hardna . The compound * Warnahardna was then shortened to Waharna . According to the linguist and onomastic Albrecht Greule , copulative compositions are a seldom documented process in the body of water names.

General

location

Catchment area of ​​the Werre

As the left tributary of the Weser, the Werre is the collecting artery of a river system that drains the Ravensberger Hügelland and the Lipper Bergland east of the Teutoburg Forest . The river rises near Bad Meinberg on the eastern slope of the Teutoburg Forest and runs parallel to its main ridge in a northerly direction. It flows through the cities of Detmold , Lage , Bad Salzuflen , Herford and Löhne . Here the direction of flow turns east to the confluence with the Weser near Bad Oeynhausen .

The Bega flows through the city of Lemgo and flows into the Werre from the right at Bad Salzuflen. From the left at Herford the Aa flows into the Werre, which among other things drains part of Bielefeld . Further down, the Else flows into the Werre from the left to the west of Löhne.

Basic data

The Werre is a left tributary of the Weser and is one of the north German rivers north of the main European watershed . According to the classic river order , the Werre has the river order number two. The water code number of the Werre, which is assigned to the Weser river system, is the number 46 . The Werre catchment area covers 1,335 km².

With a river width of around five to 35 meters, the Werre has a total length of 71.9 km. This river is no longer developed for river navigation; according to the European Water Framework Directive , the Werre is being dismantled to become a near-natural body of water. The mean flow rate at the Löhne gauge in the 1983/93 annual series is 18.3 m³ / s. The highest flow rate ever measured there was 335 m³ / s, the lowest 1.64 m³ / s and are thus roughly in the same range as the values ​​given by the topographic information service today. Due to the location of the Werre in the low mountain range, the river in the upper reaches is a fine-material, carbonate low-mountain brook (type 6), in the middle as a coarse-material, carbonatic low-mountain brook (type 7) and in the lower course as a carbonatic, fine to coarse-material rich low-mountain river (type 9.1) of the flowing water type typed.

course

Upper Werre

The source of the Werre in weirs

The elongated, 606.142 km² large catchment area of ​​the Werre from the source to the mouth of the Aa about 7.4 km below the mouth of the Begam is referred to as the Upper Werre .

The source of the Werre is located in the Horn-Bad Meinberger district of Wehren in the Lipper Bergland at 245 m above sea ​​level (NHN). It is not about a contained source, such as that of the Fulda , but rather the confluence of a few small rivulets that arise almost invisibly in the swamp areas in the immediate vicinity of the source. Directly at its source, the Werre is not even half a meter wide, a few kilometers further, in the spa gardens of Bad Meinberg , it has grown into a stately stream. From its source, the Werre initially flows in a south-westerly direction, then turns to the west after about 100 meters and flows through the Silvaticum, a 40-hectare landscape park to the west of Bad Meinberg city center. The forest landscapes from 14 regions of the world are laid out in it. East of the Silvaticum, the creek in the spa area of ​​Bad Meinberg has been dammed up to form the spa park lake since the 1950s. After this first damming, the young Werre flows in a near-natural state, meandering further northwest. It crosses Wilberg , Schmedissen and Schönemark , reaches Detmold's urban area and passes the districts of Remmighausen and Spork-Eichholz before reaching the city center. To the west of it, the Bonebach , the lower reaches of the Wiembecke , flows into the Werre, doubling the amount of water . In the further course the Werre flows through the western districts of Detmold as well as Lage and Pottenhausen , crosses the Holzhausen belonging to Bad Salzuflen and touches Leopoldshöhe in the east. The water then turns briefly north to Schötmar and reaches Bad Salzuflen . There it takes its largest tributary, the 43.9 km long Bega . Due to the damming caused by three weirs , it flows slowly through Ahmsen and after crossing under the federal highway 2 to Herford, where the Aa flows into it.

Lower Werre

Mouth of the Werre (in front) into the Weser

In Herford , at the mouth of the Aa, the Werre originally divided into several arms, in particular the Bowerre and the Kleine Werre. Both Werre and Aa were included in the city fortifications as moats in the Middle Ages and were additionally divided in the process; while the Bowerre and Kleine Werre flowed across the New Town of Herford, the (canalized) Werre was diverted around the outside. The Kleine Werre and Bowerre were filled in after the Second World War, so that today only the artificial Werre Canal exists from the Bergertor to the Aa estuary. Here the Ravensberger Mulde is reached, where the river turns to the north after the tributary of the Aa and initially forms the border between Herford and Hiddenhausen , downstream between Löhne and Kirchlengern .

At Kirchlengern the Else flows into the Werre, which there turns to the east. In the lower Werre Valley, it flows leisurely through Löhne and reaches Bad Oeynhausen . It is there on average 25 meters wide and runs in a wide valley. It is an element in the Sielpark that was included in the Bad Oeynhausen / Löhne 2000 state horticultural show .

The federal motorway 30 crosses the Werre three times between Herford and Bad Oeynhausen : the first crossing is to the west, the second north of Löhne and the third east of Obernbeck . In the course of the northern bypass of Bad Oeynhausen, the motorway will be led over two new bridges over the Werre. The Hamm – Minden railway runs parallel to the Werre for a few kilometers and crosses it between Schweicheln-Bermbeck and Löhne. The catchment area of ​​the lower Werre has a size of 879.256 km². In Bad Oeynhausen- Rehme , the Werre flows into the Weser at kilometer 190 of the Weser. The mouth height is 42 m above sea level. NN.

Tributaries

The longest tributary of the Werre is the Bega . At the confluence with the Werre, it is 43.9 km longer than the Werre, which has covered 41.6 km of the river. The catchment area of ​​the Bega with 376.727 km² is significantly larger than that of the Werre with 202.935 km² above the mouth. After the catchment area, the Else is the most important tributary with 415.518 km². In the following the tributaries of the Werre are listed in the order from the source to the mouth. The orographic location, the mouth position with indication of the stationing kilometer, the length, the size of the catchment area, the mouth height and the river code number are mentioned (note: a space has been inserted for better sortability).

Surname page Stat.

( km )
Length

( km )
EZG

( km² )
Mouth
height
( m above sea  level )
GKZ
NN right 69.8 1.7 214 46-1112
Strangbach right 62.7 3.6 5.487 152 46-112
Wörbke right 62.0 4.0 4,771 147 46-114
Gildebach right 59.5 1.1 139 46-1152
Rötkersiekbach right 59.1 1.0 138 46-1154
Dolzerbach Left 58.5 1.5 135 46-116
Little Werre right 57.4 2.3 134 46-1192
Wiembecke
(lower course: Bone Bach)
Left 54.6 18.24 47.121 119 46-12
Heidenbach Left 53.4 6.6 8,752 118 46-132
Katzenbach Left 50.8 1.7 110 46-1392
Hasselbach Left 50.1 6.5 9.311 110 46-14
Bollerbach Left 49.3 2.4 108 46-153
Rethlager Bach Left 48.2 5.4 14.794 106 46-16
Rothenbach Left 47.9 3.9 3.458 105 46-172
Haferbach Left 40.1 9.8 27.796 88 46-18
Bentgraben Left 36.4 4.2 6.831 81 46-192
Siekbach Left 35.5 4.6 3.444 79 46-196
Bexter Left 33.9 5.2 8,455 76 46-198
Bega right 30.3 43.9 376.727 70 46-2
Knipkenbach Left 29.1 4.3 6.744 69 46-32
Siekbach Left 28.3 1.3 69 46-392
Steinsieksbach right 26.0 3.4 67 46-396
Ellersieker Bach right 25.1 2.8 67 46-398
Aa Left 22.7 26.1 255.191 62 46-4
Butterbach right 22.3 4.3 59 46-512
Uhenbach right 21.9 4.5 59 46-514
Düsedieksbach Left 21.0 4.8 12,384 57 46-52
Bramschebach right 17.0 5.9 13.308 56 46-54
NN Left 14.8 1.4 55 46-592
Else Left 12.7 31.5 415,518 53 46-6
Löhner Schulbach right 11.5 3.4 51 46-72
Mühlenbach right 9.0 2.3 50 46-74
Rehmerloh-Mennighüffer
Mühlenbach
Left 8.4 16.4 70.895 50 46-8
Börstelbach Left 7.5 1.2 49 46-9112
Haubach right 7.3 2.7 49 46-912
Ostscheider Bach Left 6.8 5.4 49 46-914
Sudbach right 6.3 3.7 4,270 49 46-92
NN Left 4.8 2.8 1,550 48 46-932
Mittelbach right 4.8 8.2 13,666 48 46-94
Kaarbach Left 4.0 10.8 47 46-992
Hamkebach right 2.5 2.9 46 46-994

history

Aquatic history

Confluence of the Weser and Werre rivers in an engraving from the 17th century

The confluence of the Werre into the Weser was not always where it is today. Up until the middle of the Elster Ice Age , the Weser flowed north from Hameln to Süntel and Deister through the Deisterpforte . The Ur-Werre flowed through the Porta Westfalica , turned north of the Wiehengebirge to the west and flowed towards the north-west or west of the North Sea.

Later the Weser flowed in what is now the Weser valley and further in the original Werre-Urtal to the Porta Westfalica. North of the Porta, it initially took over the old flow direction of the river to the west until it found its way north after the ice masses melted at the end of the Ice Ages.

Settlement and State History

Since the older Iron Age and the Roman Empire, the Werre catchment area has been continuously populated by Germanic peoples. During the Migration Period and in the early Middle Ages , the Saxon settlement expanded into the region and from then on belonged to the Engern sub-area (see Angrivarians ) as part of the tribal duchy of Saxony .

In the Franconian expansion by Charlemagne and his successors, the region was Christianized , for a long time it belonged to the diocese of Minden and the Cologne church province, after its dissolution to the diocese of Paderborn . In the course of the Reformation, the majority of the residents became Protestant. During the Napoleonic Wars, the Werre valley was conquered by the French. The river marked the border between France (northwest of the Aa) and the Kingdom of Westphalia between 1811 and 1815 .

In 1815 it became Prussian again and incorporated into the administrative district of Minden , which was transformed into the administrative district of Detmold after the Second World War ; In terms of water law, the Werre is subordinate to the upper water authority of the government in Detmold.

Around 390,000 inhabitants now live in the Bega and Werre area. With today's forms of housing and settlement, this also leads to a high degree of landscape sealing. This leads to rapid runoffs in the upper reaches of the waters when there is heavy rainfall.

Hydrology

Catchment area

The catchment area of ​​the Werre with Bega, Aa and Else

The Werre catchment area stretches across the western Lipper Bergland and almost the entire Ravensberger Mulde between the eastern wings of the Wiehengebirge and Teutoburg Forest . The total area of ​​the lively catchment area is 1485.4 km². 1289.0 km of this are in North Rhine-Westphalia and 191.0 km in Lower Saxony . The rainfall in the catchment area averages 800 millimeters per year. The total annual precipitation increases from north to south and amounts to 700-800 millimeters in the northern catchment area south of the Wiehengebirge, 800-900 millimeters in the central part and 900-1000 millimeters in the south of the catchment area. Peak values ​​of up to 1200 millimeters per year are measured on the ridge of the Teutoburg Forest ( Veldrom ). 59.2% of the area of ​​the Werre catchment area is used for agriculture, 15.6% is covered by forest. The proportion of open areas is 19.0% and the proportion of sealed areas 6.2%. The mean population density in the Werre catchment area is 460 inhabitants per square kilometer.

Large parts of the catchment area are covered by loess , which is transported into the valley by the waters. The bed substrate consists of mountain material such as sandstone , keuper and limestone . Above all, the Aa and the Else deliver large amounts of sand, which is deposited on the embankments after floods and is clearly visible on the foreland.

Monthly mean of the Werre discharge at the Löhne gauge (1982–2005)

The catchment area of ​​the Werre is connected to the catchment area of ​​the upper Hase via the bifurcation of the Else from the Hase . Usually this is not counted as part of the Werre catchment area, but to that of the hare. There is also a connection to the Ems catchment area via the Bielefeld Lutter . It was dug up in 1452 by the Gütersloher Lutter just behind the source (the Lutterkolk) and partly diverted to the northeast. The catchment area of ​​the Werre extends over the Else in the west to Lower Saxony.

The Teutoburg Forest, which borders the Werre catchment area in the west and south, represents a watershed . In the west of the Werre catchment area it forms a section of the Weser-Ems watershed and in the extreme south of the Werre catchment area a section of the Rhine-Weser watershed . The border point of these watersheds is marked with the three river stone . Creeks such as the Hasselbach or the Wiembecke that arise on the northern slope of the Teutoburg Forest are direct or indirect tributaries of the Werre, which flows into the Weser. In contrast, the Hessel or Strothe , which have their origin on the southern slope or in the foreland ( Senne ) of the Teutoburg Forest, flow into the Ems or over the Lippe into the Rhine.

Water flow

The discharge at the Löhne gauge, the last gauge before it flows into the Weser and thus taking into account 89.9% of the water flow in the catchment area, is 4.32 m³ / s at low water (MNQ) and 18 at average water level (MQ). 1 m³ / s and at high water (HQ) 191 m³ / s. The highest discharge ever measured was recorded at the Herford gauge in 1960 with 246 m³ / s and at the Löhne gauge in 1986 with 340 m³ / s. The Werre had the lowest amount of water at the Herford gauge with 1.21 m³ / s on October 11, 1959 and 2.15 m³ / s at the Löhne gauge on August 6, 1996. The highest runoffs are generally recorded in the winter months. Low water prevails in the summer months.

The mean flow velocity is around 0.3 m / s. The water needs about 57 hours from the source in Horn-Bad Meinberg / Wehren to the mouth in Bad Oeynhausen, i.e. 2 days and 9 hours.

Water quality

Water quality

The Werre as the receiving water of the central
sewage treatment plant in the city of Lage. At the time of admission, the discharge volume was increased due to heavy rainfall.

Around 1900 the Werre was still a biologically intact, clean and fish-rich river. It was only with the onset of industrialization at the end of the 19th or the beginning of the 20th century and the associated strong increase in population, settlement areas and infrastructure that the Werre began to be polluted by wastewater from industry, commerce, agriculture and private households. A further increase in the pollution of the Werre began after 1945, as population growth began after the Second World War and more wastewater from households ended up in the river due to the lack of sewage treatment plants. In addition, the amount of wastewater supplied to the Werre from the factories increased, because in the course of the creation of jobs, new factories with inadequate treatment technology were built or existing ones expanded. For many years the Werre was like a sewer. In 1969/1970 the Werre was so polluted that most of the sections were assigned to water quality classes III (heavily polluted) and III-IV (very heavily polluted). In some sections, especially below Herford, the Werre was so heavily polluted that it was rated as water quality class IV (excessively heavily polluted). Although the first cities and municipalities along the Werre had already started to build mechanical sewage treatment plants in the 1950s, there was no noticeable improvement in the desolate quality situation. This only changed gradually from the 1970s, when a rethinking of municipalities and cities became noticeable and more investments were made in wastewater treatment systems. The quality situation has been significantly improved, but the Werre is still exposed to numerous pollution: it is already exposed to pollution from household and agricultural wastewater just a few 100 meters after the source area and must be rated with water quality class II-III. In the further course, the water quality situation of the Werre improves again, so that the Werre section from Horn-Bad Meinberg to Detmold can be assigned to water quality class II (moderately polluted). In the local passage of Detmold up to the confluence of the Bonebach on the western outskirts, the Werre shows a higher degree of pollution and is rated with water quality class II-III. With the confluence of the Bonebach, which is also assigned to water quality class II in the lower reaches, the quality situation improves again to water quality class II. Between the confluence of the Bentgraben and the Bexterbach, the Werre has locally deteriorated water quality and is critically polluted (water quality class II-III) . After a local quality improvement to water quality class II, the local passages of Schötmars, Bad Salzuflens and Ahmsens must be assessed again with water quality class II-III. Overall, the Upper Werre can be assigned to water quality class II. According to LAWA, watercourses of water quality class II are sections of water with moderate pollution and a good oxygen supply. They are characterized by a very large biodiversity and individual density of algae, snails, small crustaceans and insect larvae. Aquatic plants can cover larger areas. In addition, waters belonging to water quality class II are species-rich fishing waters. From Herford, the Werre is classified as critically polluted and retains this water quality class until it flows into the Weser below Bad Oeynhausen.

The pollution of the Werre results from its tributaries and diffuse pollution from mixed wastewater and surface sewers as well as from substance inputs from agriculture such as nitrates (fertilizers) and pesticides . In addition, the Werre is polluted by one industrial and nine municipal wastewater treatment plants . In addition to the Horn-Bad Meinberg sewage treatment plant, the Detmold, Lage, Leopoldshöhe / Heipke, Bad Salzuflen, Herford , Hiddenhausen-Schweicheln-Bermbeck, Löhne and Bad Oeynhausen sewage treatment plants as well as the sugar factory in Lage discharge their wastewater into the Werre. Added to this are the discharges from 19 municipal sewage treatment plants into the tributaries of the Werre, which also pollute the Werre. Accordingly, in times of low rainfall, treated wastewater from the municipal sewage treatment plants makes up a large part of the water flow from the Werre, which is reflected in a deteriorated water quality. In addition, there are numerous direct discharging operations in the Werre catchment area that treat wastewater such as cooling water from the Kirchlengern power plant , production wastewater or rainwater, depending on the degree of pollution, or discharge it untreated directly into rivers. Furthermore, after the confluence of the Bega in Bad Salzuflen, the Werre shows a high level of chloride pollution, which results from the introduction of mostly unused brine from the state bath Salzuflen via the salts and the Bega. Another stress factor is the concentration of industry, trade and residential developments in the Werre catchment area.

Water structure quality

The water structure quality provides information about the ecological quality of the water structures and the dynamic processes indicated by them. After that, rivers are classified on a seven-point scale (1 = unchanged, 7 = completely changed).

The natural water structure of the Werre was largely damaged by the aforementioned corrective measures and hydraulic engineering interventions and the physiognomy of the river was fundamentally changed.

Only a few sections of the Upper Werre have remained in a near-natural state. This includes above all the section of water below Bad Meinberg. Structural quality class II was awarded there only once. Another route, which has only been slightly changed by construction work, is located between Detmold at the confluence of the Heidenbach and the city limits of Lage. This section received the structural quality class 3 to 4 (moderately or significantly changed). The same applies to the approximately 13 kilometer long Werre section between Lage and Schötmar, which is also rated alternately with structural quality classes 3 and 4. In the further course the Werre is much more changed. From the confluence of the Bega to the confluence of the Werre into the Weser, it is very much or completely changed (structural quality classes 6 and 7). The four-kilometer middle section of the stretch of water between Herford and the Else estuary is an exception. The water structure there is significantly to severely damaged. Especially in the local passages it has been changed significantly. The local passages of Horn-Bad Meinberg and Detmold belong to structural quality class 5 (outskirts) and 7 (city center). Within the Lagenser core city , the water structure is altered slightly less than in the local sections of the other cities on the Upper Werre. It is seen as greatly changed. Added to this is the large number of 52 transverse structures . This means that there is an average of 0.7 transverse structures per Werre kilometer or there is one transverse structure every 1.4 kilometers. Transverse structures are detrimental to an intact river ecosystem because, in the absence of a fish passage , they represent an obstacle to the migration of animals, especially fish.

In recent years, in connection with the European Water Framework Directive (WFD), there has been a noticeable rethinking of environmental and river protection. The aim of the guideline is to bring the running water into a good ecological status so that the water structure is upgraded. Measures to improve the water structure have already been carried out at the numerous small tributaries as well as directly at the Werre. In Detmold below the confluence of the Bonebach, for example, renaturation measures have been taken.

For the Werre area there is the “Water Development Plan Weser Werre Else”, which implements the goal of the Water Framework Directive, which prescribes a “good ecological status” for our water bodies by 2015, with many stakeholders.

The course of the Werre at Meschesee in Detmold is close to nature

Expansion and correction

Similar to many other rivers in Germany , hydraulic engineering measures were also carried out on the Werre with the intention of increasing agricultural production, creating settlement areas, protecting them from flooding and harnessing the river's hydropower.

The Werre was expanded in almost all local passages. In Detmold, the buildings reach right up to the Werre, which is lined with a rectangular profile with concrete walls on the banks and runs in a base made of armourstone. The same applies to the inner city of Bad Meinberg, as the buildings there directly reach the river. The influence on the structure and the change in the profile of the Werre is a consequence of the development and the associated increase in area of ​​the cities.

The local passage in Lage is expanded along its entire length, which went hand in hand with the development of the settlement and the use of hydropower at the Lage weir. In 1952 a flood ditch was completed at the Werreanger school and sports center , which significantly relieves the actual river bed during floods. Outside the local passage, to the west and east of the main town of Lagens, the Werre was relocated and expanded. This was related to the extraction of sand and gravel, which required partial relocation of the Werre. The Lagens upgraded line is seven kilometers long. From Alt-Holzhausen onwards, the water structure was changed in the entire municipal area of ​​Bad Salzuflen. The body of water was expanded and partially relocated for reasons of flood protection and the use of hydropower as well as for cultural reasons. While hydraulic engineering measures were only partially carried out on the Upper Werre, almost the entire Lower Werre was changed.

From Herford the course of the Untere Werre begins, which was expanded on the flow route between Herford and Hiddenhausen in order to enable better agricultural use of the valley area. Existing meanders were pierced and the barrel was shortened. The Werre is also regulated and developed in the further course up to the confluence with the Weser. The urban area of ​​Löhne has younger and older upgraded routes of the Werre. A special feature of the old extension from the end of the 19th century, which helped the Werre to maintain its unchanged appearance to this day, is the edge dike between Löhne and the Siel weir in Bad Oeynhausen. The new upgraded line, which ends upriver at the Kissler weir near Oberbehme , was built in 1982 as part of the construction of the Löhne flood retention basin.

The most developed stretch of water is the 5.7 kilometer long stretch of water below the Siel weir to the mouth of the Weser. Numerous hydraulic engineering measures were carried out there in order to protect Bad Oeynhausen and Löhne from flooding . Originally, numerous meanders, some of which ran in opposite directions, shaped the image of the Werre, which were pierced in the course of these measures. The resulting shortening of the course was accompanied by an increase in the bottom slope and thus an increase in the flow velocity, which was to be compensated for by basic thresholds. The expansion in the Bad Oeynhauser urban area happened in the 1970s. Testimony of the former course is an oxbow lake of Werre north of Sielparkes in Bad Oeynhausen. Today the Kaarbach runs 300 meters through the western part of the oxbow lake and thus in the original bed of the Werre. As early as 1900, a discontinuous dike line was built on both sides of the Werre between Löhne and Bad Oeynhausen - probably as a reaction to the November floods in 1897.

Similar interventions and measures were carried out on the large Werre tributaries, Bega, Aa and Else.

River straightening between Bad Salzuflen and Herford

View downstream of the straightened Werre near Ahmsen. You can also see the Ahmsen gauge and the crossing of federal motorway 2 .
Werreufer in Herford (Lübbertor, formerly the Herford small railway line )

Originally the Werre meandered very strongly between Bad Salzuflen and Herford. The Werre was around 100 km long at the time, around 30 kilometers longer than it is today. The reasons for the strong meander formation were the low bed gradient of the Werre in this section and the associated low flow velocity as well as the high sand content, which resulted mainly from the sand input from the Bega. The sand carried along sediments in low water phases, making the river bed higher. As a result, the river overflows faster when the water level rises, and floods are frequent. Therefore, after heavy rainfall, floods often occurred, which flooded the entire agricultural floodplain of the Werre, so that the stretch of water between Bad Salzuflen and Herford resembled a lake landscape. The recurring floods caused great damage to the Werre neighbors.

From 1770 onwards, thought was given to how the situation could be improved and in 1772 the so-called Werre Commission was founded . This should work out a final plan with a longer-term effect, since the excavations of the river bed in 1716, 1737 and 1755 only brought short-term success. The plan drawn up by the Werre Commission envisaged the piercing of all meanders so that a long straight canal should be created. A few weeks later, the building permit was granted and in the summer of the same year construction work began to transform the Werreaue into a large construction site. The expansion measure was carried out in three stages: The Bega was canalised between Lindemannsheide east of Bad Salzuflen and the confluence with the Werre. The Werre between Heerse and the Knonhof, which is now west of Schötmar, was straightened, creating the 1.7 kilometer long Werre Canal. Shortly before Schötmar, the water of the Bega Canal was channeled into the old Werre river bed, which meets the new Werre Canal near today's Bega estuary. In the third section, the meanders were pierced up to the then Lippe state border at Ahmsen, so that a total of 4 kilometers long canal was created, which was named Lippischer Canal . As a result of the corrective measures, the course of the Werre between Schötmar and the border with the Herford district was shortened from 12 to 6.8 kilometers. In 1774, the Herford residents of Werrea advised on a continuation of the canal to the Berger Tor southeast of the city center of Herford, but initially decided unanimously against this option, as the project would have caused enormous costs that they were not prepared to bear. In 1783, after another strong flood below the end of the Lippe Canal, opinion changed. On May 9, 1786, the Herford War and Domain Chamber granted building permission to pierce the remaining meanders between the border and the Berger Tor. Construction work on the border began that same month and was completed after a month. The straightening measures gave the Werre a wide trapezoidal profile and is accompanied on the right by an earth wall. In Herford, the Werre above the Berger Tor weir resembles a canal. The Werre below the Berger Tor was significantly influenced by the development of the city of Herford, relocated and expanded several times. In the 13th century, when the new town was founded, the water was moved behind the city wall and diverted around the city. This was intended to serve as a defense facility for the residents of the Neustadt. The former course of the Werre, the Bowerre , was filled in in 1972.

Utility waters and economic factor

The Werre was used in many ways early on. The most decisive role here is played by the milling industry, which made use of the water power of the Werre, which the river provides with its very high water flow and flow speed. As early as the 12th century, some water mills and dams were built along the Werre and its numerous tributaries, which made use of the water power. A total of four large water mills were built on the Upper Werre and one on the Lower Werre, as well as a hydroelectric power station .

Milling industry

The weir in position

A mill in Lage, first mentioned in 1370, is still in operation. There the Werre is dammed by two weirs and divided into three arms. Originally there was a river island there. The first arm is the main arm of the original river bed behind the large weir and is only water-bearing during floods. A canal branches off most of the water and directs it through the mill before it re-enters the actual river bed. The small weir regulates the outflow into the Mühlengraben, which serves as flood relief and flows back into the Werre after 250 meters. The animal feed company Altromin is located on the site.

The oldest mill was the Heerser mill near Bad Salzuflen, which was mentioned in 1358, a grain mill that was in operation until it was destroyed by fire in 1925. In 1927, the preparatory work for the construction of a hydropower plant began, which went into operation partially in February and fully in April 1928. The power plant already proved to be profitable in the first few months of operation. The Werre was dammed by means of a weir, so that there was a height difference of 3.90 m. A water volume of 2000 liters per second drove two Francis turbines , which started two three-phase synchronous generators . The plant was in operation until the 1970s, but was then shut down and dismantled due to inefficiency. The Heerser Mühle Environment Center is now located on the site . The weir system was torn down and the associated sill removed to restore the passage for fish and small organisms.

There are two more mills on the Upper Werre. The Düvelsmühle southwest of the Waddenhausen district of Lagens has long been out of service and houses an amusement arcade . In the Bad Salzufler district of Wülfer there was the former Wülfer mill and the associated mill weir, which had fallen into disrepair and was leveled. The resulting bottom slope was replaced by a rough bottom slide and the bank was paved with stones. On the Untere Werre, south of Löhne, the Oberbehmer mill was built with the Kissler weir . After operations ceased, the buildings were converted into a hotel.

Power generation

Werre weir in Herford at Bergertor

In Bad Oeynhausen, the Werre has been dammed by the sluice weir since 1753 and part of the water is directed into the Kokturkanal that branches off above the weir and flows through the sluice park. The water was initially used to generate energy to extract salt from brine . After the salt production was stopped, the power plant served as a supply facility for the spa in Bad Oeynhausen.

Another hydropower plant was to be built at Bergertor in Herford. In order to be able to install the turbine, the existing weir system had to be converted. The project was discontinued by Stadtwerke Herford in mid-2010 for cost reasons.

Timber transport

Raftsman monument at the mouth of the Werre in Bad Oeynhausen

The Werre was mainly used in the 18th and 19th centuries as a water transport route for wood from felled trees from the Lipper Bergland. They were rolled down into the river and tied up in rafts and shipped down to the valley. The rafting monument at the mouth of the Werre in Bad Oeynhausen is a reminder of this branch of industry, even if rafting was much more strongly represented on the Weser and its upper reaches.

Meadow rafting

Another use of the Werre was the meadow rafting, a method of fertilizing and irrigating the agricultural areas along the Werre. To do this, the river was dammed for a short period of time so that the meadows along the river were flooded. The aim of this method was to increase the agricultural yield . This method was mainly used in Lippe and on the Werre in the second half of the 18th century and was only discontinued in the 1930s with the advent of artificial fertilizers .

fishing

The Werre, which is rich in fish, has always been fished commercially . At the beginning of the 20th century there were trout, pike and salmon in the Werre, which were caught by professional fishermen and were sold regionally but also at the fish market in Minden.

nature

Nature reserves

The Werre in the Holzhauser Bruch nature reserve

The course of the Werre is part of several nature reserves . Together with its lowland, it is part of the 56-hectare nature reserve Werreniederung and Haferbachtal . In addition, the Werre flows in the area of the city Bad Salzuflen the Holzhauser break , a 40-hectare nature reserve, which includes a portion of the flood plain with wood fringes, forest areas and grassland. The 25.6 hectare Heipker See nature reserve connects directly to the northwest of this nature reserve . In the Bad Salzufler area there is also the In der Masch nature reserve , a 23.30 hectare grassland complex in the floodplain of the Werre. The nature reserve Bramschebach- Nagelsbachtal in Herford encompasses a widely branched and extensive sieve system on 105 hectares.

fauna

Kingfisher (Alcedo atthis) with a captured gudgeon

The upper reaches of the Werre, the stretch of water between the source and the mouth of the Rethlager brook, is classified as one of the fishing waters of the Upper Trout Type Medium Mountains and Lower Trout Type Medium Mountains . Mainly fish live in this section, which prefer sections with high currents (rheophilous). The main fish is the brown trout . The most important companion species are brook lampreys and poppies . The further course of the Werre belongs to the grayling type low mountain range . The grayling is the main fish there. All of the companion species typical of this river region occur, namely minnow , loach , chub , nose and gudgeon . In addition, other fish species, which belong to the barbel and Brass region where Werre home: pike , roach , rudd , eels , river gruff , sculpins , sticklebacks , barbel , loach , loach and moderlieschen .

The wolffish receives special attention, because in the Else and Werre river systems it occurs in abundance of individuals. As a result, the river system is included in the Natura 2000 classification with the primary goal of maintaining and optimizing the quality of the habitat.

The rare kingfisher , which is one of the endangered species, can be observed at the Werre . Interventions in the river systems, such as the flattening of the steep banks in which the kingfisher builds its nesting caves, have greatly reduced its habitat and the species has become increasingly endangered. The pollution of the Werre also caused the number of kingfishers to drop drastically, as the polluted water offered no habitat for fish species such as trout, minnows and sticklebacks.

In addition to the kingfisher, many other bird species can be found on the Werre, such as the dipper , another endangered species of bird, and the gray wagtail . In addition, water rails , various ducks , including above all the mallard duck and gray heron , which remain motionless on the riverbank and prey on fish and frogs, and coots can be observed. The water bat is native to the Werre. There are also a large number of other animal species, some of which are threatened, in and around the Werre.

Flood

history

Werre in Bad Oeynhausen

There is little evidence of the flood history on the Werre. At the Hansastraße gauge in Herford there are high water marks from around 100 years. The worst flood on the Werre occurred during the recording period in 1946, when the level on Hansastraße in Herford was 5.69 meters. It was a supra-regional flood with catastrophic phenomena on the Weser, Lippe , Ems and IJssel . It was caused by high precipitation in connection with frost. Further strong floods occurred in 1909, 1925, 1960 and 1970 and 1986 (4.10 m Herford gauge, 335 m³ / s at the Löhne gauge).

On 27./28. In October 1998, a flood, which mainly affected the area of ​​the Upper Werre and was caused by heavy precipitation of 40-50 millimeters per day after extraordinary rain, caused enormous damage in Detmold, Lage and the smaller towns. Parts of the West industrial area in Detmold were flooded and some of the companies located there suffered high damage due to massive flooding. In addition, the dike of the Meschesees between Detmold and Lage, which the Werre flows around, threatened to break. 160,000 cubic meters of water from the Werre poured into the lake on the northeast bank and caused the lake level to rise sharply. A breaking of the dam on the opposite bank would have caused a strong tidal wave and led to the most devastating flooding in Lage after the 1946 flood. The breaking of the Mescheseedamm was barely prevented thanks to the work of 160 THW members and the situation was spared.

Flood protection

The Werre Water Association, based in Herford, is responsible for supra-local flood protection in the Werre catchment area . It was founded in 1976 by the districts of Minden-Lübbecke, Lippe, Gütersloh, Herford and the city of Bielefeld and currently operates three flood retention basins (HRB) in the Werre catchment area. Together they have a retention area of ​​around 5.5 million m³.

The Löhne flood retention basin with a catchment area of ​​1,335 km² is located directly on the Werre. The retention volume is 2.5 million m³ (specific retention area 1,873 m³ / km²). The storage area in the event of a full jam is 135 ha. The standard or basic rate is 380 m³ / s. The destination is at 55.70 m above sea level.

The Bega flood retention basin is located on the tributary of the same name above Bad Salzuflen in the area of ​​Ostwestfalenstrasse.

The Bustedt flood retention basin is located on the Brandbach in Hiddenhausen in the area of ​​junction 28 of the BAB 30.

Two further flood retention basins and a polder are being planned. The Wiembecke flood retention basin is being built above Detmold, the Werre flood retention basin south of Bad Salzuflen and the Bünde polder above Bünde in the Else-Bruch.

In addition to the flood retention basins, retention areas play an important role in flood protection. Retention spaces are areas in the floodplain that lie to the side of the river. During floods, water can spread and collect on these areas. This reduces the flood discharge of the river and lowers the water level. In addition to the municipalities 'and municipalities' flood plains along the Werre, two large retention areas are planned. These extend along the Werre near Ahmsen between Bad Salzuflen and Herford and between Löhne and Bad Oeynhausen from the crossing of the federal motorway 30 east of Löhne and the Sielwehr in Bad Oeynhausen. Lake retention is also possible, in which lakes serve as retention areas. The Werre water association is planning two lake retention areas between Detmold and Lage and between Lage and Holzhausen . These lakes were created by gravel mining in the Werre Valley. In addition, there are floodplains in the catchment area near the cities of Blomberg, Detmold, Lage and Lemgo.

The Werre Water Association also operates 20 gauges and makes the water level data available online. Current flood warnings and water level data can also be found on the website of the State Office for Nature, Environment and Consumer Protection in North Rhine-Westphalia (LANUV NRW). It operates a total of 10 gauges in the Werre catchment area.

Flood behavior

The precipitation-runoff behavior of the Werre is characterized by the predominantly cohesive soils of the catchment area and the lively relief . The runoff concentration occurs quickly and depends on the fore-soil moisture . The higher the fore-soil moisture, the greater the proportion of precipitation that drains and fills the valleys right into the buildings. Due to the relatively large size of the catchment area, the Werre only rises exceptionally when there is extensive, long-lasting heavy rainfall . The overlapping of the flood waves of the Else, the Aa, the Bega and the Upper Werre does not always follow the same principle. The pulling of the rain fronts, which cause the loads to turn out differently for each event, can cause unfavorable but also favorable, time-shifted apex overlays in the course of the Werre.

Sights and buildings

The Werre flows through the cities of Detmold, Bad Salzuflen, Herford, Löhne and Bad Oeynhausen. The Werre-Weser-Kuss Bridge is located at the mouth of the Werre, the "Werre-Weser-Kuss". In Bad Oeynhausen, a large shopping center, the Werrepark, was built in 1998 directly on the Werre on the site of the abandoned Weserhütte .

tourism

The Else Werre cycle path between Löhne and Bad Oeynhausen

When the water levels are good, the Werre can be used by canoeists from Detmold or from Lage , although trips are regulated for nature conservation reasons and must be registered. The canoeing clubs in the area are the Herford Canoe Club e. V. (with slalom course and campsite), the canoe club Löhne e. V. and the canoe club Bad Oeynhausen e. V. Between Löhne and Bad Oeynhausen the Else-Werre-Radweg leads along the Werre. The 71 km long Werre cycle path leads from the source of the Werre near Bad Meinberg to the mouth of the river in the Weser near Bad Oeynhausen along the Werre.

literature

  • Rainer Pape: Charming Werretal. Between the Teutoburg Forest and Porta Westfalica . Heka Verlag, 1995, ISBN 3-928700-15-4 .
  • Altenhöfer-Westenhoff, Karsten and Wagner, Bernd Josef: History in the river. On the environmental history of Werre and Else in eastern Westphalia . Publishing house for regional history, Bielefeld 1997, ISBN 978-3-89534-203-5 .

See also

Web links

Commons : Werre  - collection of images

Footnotes

  1. a b c German basic map (DGK 5) in Topographical Information Management, Cologne District Government, Department GEObasis NRW ( information )
  2. a b c Topographical Information Management, Cologne District Government, Department GEObasis NRW ( information )
  3. ^ German Hydrological Yearbook Weser-Ems 2014. Lower Saxony State Agency for Water Management, Coastal Protection and Nature Conservation, p. 164, accessed on October 4, 2017 (PDF, German, 8805 kB).
  4. ^ Albrecht Greule: German water names book. Etymology of the water body names and the associated area, settlement and field names. de Gruyter, Berlin / Boston 2014, ISBN 978-3-11-019039-7 , p. 585.
  5. a b c Waters profile Werre - Part 1 ( Memento of the original from November 5, 2013 in the Internet Archive ) Info: The archive link was automatically inserted and not yet checked. Please check the original and archive link according to the instructions and then remove this notice. (PDF; 187 kB) @1@ 2Template: Webachiv / IABot / daten.flussgebiete.nrw.de
  6. Marc Schwientek: Diploma thesis: Tritium balance modeling by combining the TACD and TRIBIL models in the macroscale catchment area of ​​the Weser (PDF; 1.8 MB), Institute for Hydrology at the Albert Ludwig University of Freiburg i.Br. January 2004
  7. Stat. = Water stationing
  8. orifice layer (at / near) the tributaries according to the flowing water kilometrage of Werre
  9. Topographical Information Management, Cologne District Government, Department GEObasis NRW ( Notes )
  10. a b Water directory of the State Office for Nature, Environment and Consumer Protection NRW 2010 (XLS; 4.67 MB) ( Notes )
  11. For a better overview and sorting downstream, a hyphen has been inserted for each river in the water code number (GKZ) after the number "46", which stands for the Werre .
  12. Rainer Pape: Charming Werretal: between Teutoburg Forest and Porta Westfalica . Heka-Verlag, Leopoldshöhe 1995, ISBN 3-928700-15-4 , p. 10 .
  13. Explanatory report on the rivers in North Rhine-Westphalia: The second management plan for NRW  ( page no longer available , search in web archivesInfo: The link was automatically marked as defective. Please check the link according to the instructions and then remove this notice. , Ministry for the Environment and Nature Conservation, Agriculture and Consumer Protection of the State of North Rhine-Westphalia (MUNLV), September 2008, accessed on November 6, 2013, from wrrl.flussgebiete.nrw.de (PDF; 3.6 MB)@1@ 2Template: Toter Link / wrrl.flussgebiete.nrw.de  
  14. a b Waters profile of the Werre at www.flussgebiete.nrw.de ( Memento of the original from November 5, 2013 in the Internet Archive ) Info: The archive link was automatically inserted and not yet checked. Please check the original and archive link according to the instructions and then remove this notice. (PDF; 326 MB) @1@ 2Template: Webachiv / IABot / daten.flussgebiete.nrw.de
  15. a b c d ELWAS-WEB. Electronic water management network system for water management in NRW
  16. a b c d e f g h i Flood Action Plan Werre ( Memento from November 5, 2013 in the web archive archive.today ), from bezreg-detmold.nrw.de
  17. German Hydrological Yearbook Weser-Ems-Area 2005
  18. a b c Lydia Bünger: Waters and historical fishing in Lippe . Ed .: Rainer Springhorn . Natural science and Historischer Verein für das Land Lippe, Detmold 1996, ISBN 3-924481-07-5 , p. 7, 13 ff., 75 ff .
  19. Water quality map 1969/1970, Lippe district
  20. Water quality map 2003, Lippe district
  21. Water quality report 2001 ● State Environment Agency North Rhine-Westphalia - Weser. Archived from the original on September 25, 2011 ; accessed on November 2, 2016 . , State Office for Nature, Environment and Consumer Protection North Rhine-Westphalia (2001), on lanuv.nrw.de (PDF; 964 kB)
  22. Water structure quality map of the state of North Rhine-Westphalia, status: 2005
  23. Weser-Werre-Else water development project , accessed on October 28, 2013.
  24. a b Along the "Werre" in Hiddenhausen , hiking portal of the Herford district, accessed on November 5, 2013, on Kreis-herford.de
  25. a b Karsten Althöfer-Westenhoff; Bernd Josef Wagner: History in the river: on the environmental history of Werre and Else in eastern Westphalia . Publishing house for regional history, Bielefeld 1997, ISBN 3-89534-203-3 , p. 21-26 .
  26. History of the Heerser Mühle , on wasserkraft-heerser-muehle.de
  27. Water project "Water in the river" ( Memento of the original from March 5, 2016 in the Internet Archive ) Info: The archive link was automatically inserted and not yet checked. Please check the original and archive link according to the instructions and then remove this notice. , accessed on April 16, 2010, at lippe.de @1@ 2Template: Webachiv / IABot / www.lippe.de
  28. Sielwehr ( Memento of the original dated November 5, 2013 in the Internet Archive ) 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. , as a copy of the minutes of the 11th meeting of the Committee for Urban Development on October 26, 2006, Bad Oeynhausen, on badoeynhausen.de (PDF; 60 kB) @1@ 2Template: Webachiv / IABot / www.badoeynhausen.de
  29. ^ "In der Masch" nature reserve in the specialist information system of the State Office for Nature, Environment and Consumer Protection in North Rhine-Westphalia , accessed on February 24, 2017.
  30. ^ "Bramschebach-Nagelsbachtal" nature reserve in the specialist information system of the State Office for Nature, Environment and Consumer Protection in North Rhine-Westphalia , accessed on February 24, 2017.
  31. ^ System Else / Werre ( Natura 2000-Nr. DE-3817-301 ; Naturschutzinformationen Nordrhein-Westfalen), accessed on March 19, 2014
  32. ^ THL Hochwasser in Detmold , report by THW-Detmold, on thw-detmold.de
  33. Flood protection , in surface waters (homepage of the lower water authority of the Herford district), accessed on November 6, 2013, onkreis-herford.de
  34. Werre-Wasserverband (Internet presence of the Werre-Wasserverband), accessed on August 18, 2010, on werre-wasserverband.de
  35. Announcement of the Detmold district government of June 4, 2009 in the official gazette , on bezreg-detmold.nrw.de (PDF; 72 kB)
  36. "Ötternbach" floodplain map , on bezreg-detmold.nrw.de (PDF; 1.8 MB)
  37. Floodplain map "Passade" , on bezreg-detmold.nrw.de (PDF; 1.7 MB)
  38. Water levels (Werre-Wasserverband), accessed on October 28, 2013, from werre-wasserverband.de
  39. Level raw data: HYGON ( hydrological raw data online , at the State Office for Nature, Environment and Consumer Protection North Rhine-Westphalia; LANUV), u. a. der Werre, accessed on October 28, 2013, at luadb.it.nrw.de
  40. Canoeing on the Werre (from the Lippeservice of the Lippe district, accessed on October 28, 2013, from Kreis-lippe.de)
  41. Else-Werre-Radweg , in Cycling in and around Löhne , accessed on October 28, 2013, on loehne.de