Kemnader lake

Kemnader lake
	Kemnader See with a view to the east
Tributaries:	Ruhr , Oelbach
Major cities nearby:	Bochum , Hattingen and Witten
	North Rhine-Westphalia , Germany
Coordinates	51 ° 25 '23 " N , 7 ° 15' 59" E Coordinates: 51 ° 25 '23 " N , 7 ° 15' 59" E
	Data on the structure
Construction time:	- 1979
	Data on the reservoir
Altitude (at congestion destination )	72 m above sea level NN
Water surface	1.25 km²
Reservoir length	3 km
Reservoir width	420 m i. M.
Storage space	3 million m³
Particularities:	Fish ladder and boat lane next to the barrage
	View from the weir
	Gibraltar colliery Play media file Bochum - Kemnader Straße - Kemnader See - Weir - Bootsgasse (weir bridge)

The Kemnader See lies between Bochum , Hattingen and Witten . It is the youngest of six Ruhr reservoirs . The construction of the reservoir was part of the Ruhr University's planning . It was laid out by the Ruhr Association and completed in 1979. The content is around 3 million cubic meters of water at an average height of 2.4 meters. Hiking and cycling trails surround the lake. The circular route around the reservoir is about 8 kilometers long.

The Kemnader See belongs to the theme route 12 - Past and present of the Ruhr and to theme route 29 - Bochum - industrial culture in the heart of the area of the route of industrial culture .

History and construction

In the Gibraltar colliery on the western shore of the lake, hard coal was mined from 1786 to 1925 . A memorial plaque on a building of the colliery, today the boathouse of the Ruhr University Bochum , reminds that one of the first concentration camp outposts in Bochum and a torture room of the Witten NSDAP was located here during the National Socialism .

As early as 1929, for reasons of water management, plans were made to dam the Ruhr between Haus Herbede and Haus Kemnade . A local recreation was quickly discussed. However, the advocates of the project failed at that time. After the Ruhr University Bochum was founded in 1962 , plans for a local recreation area were in demand. In 1966, the state of North Rhine-Westphalia called for the development of congestion projects ; the groundbreaking ceremony did not take place until 1976.

First of all, the later shores of the lake were created by ramming sheet piling into the ground. Within three years, 3 million cubic meters of earth - the later damming area - were mined and a weir was built on the south bank. In mid-1980 the pool was full and the opening of the lake was celebrated on September 18, 1980 with a festival for water sports enthusiasts.

In October 2009 it became known that the Ruhrverband is building a hydropower plant on Lake Kemnader. Construction began in spring 2010. The power plant, which works with a Kaplan turbine , generates up to 3.5 million kilowatt hours of electricity annually. The circular route over the weir was closed during the 20-month work . The work was completed in October 2011 and the power plant was put into operation. It supplies energy for the equivalent of 1200 households.

Water management

The Oelbach also flows into the lake , which, coming from the south of Bochum , carries previously treated sewage from the districts of Langendreer , Werne, Querenburg and Steinkuhl. The lake was created to regulate the amount of water in the Ruhr and to improve the water quality - the suspended particles should sink in it.

In 2001, the Ruhr down wandering reached waterweed (Elodea canadensis and Elodea nuttallii) the lake. It needs light to the bottom of the lake and is therefore an indicator of good water quality, but thrives too well here. In order to combat them, temporary drainage over winter was even considered, which would only have had short-term success, but otherwise would have had too many ecological side effects. Many sea birds overwinter on the lake.

On the Ruhr in the vicinity of the lake, fish-eating birds such as cormorants , kingfisher and gray herons are no longer uncommon. On the banks of the river you can also find the shells of freshwater mussels up to 10 cm in size.

On the southern bank next to the weir there is a boat lane that allows canoes and rowing boats to pass through the barrage. When the power plant was built, a fish ladder was built on the northern bank next to the weir. A bypass pipe allows smaller fish to travel downstream through the turbine.

Recreation

Marina in Heveney

The Ruhr University is located high above the lake

Soon after its opening, the lake also became very popular as a local recreation area. However, the parallel A 43 (released in 1971) and power lines on the south-eastern bank impair the attraction of the circular route. In the past few years, the nearby parking spaces were often overcrowded on the weekends (the lake is not yet optimally connected to local public transport) and there have even been accidents between pedestrians, cyclists and inline skaters on the circular routes.

Due to the high number of visitors, consideration was given to creating another lake downstream near Hattingen . On the other hand, the river there, with its groynes and hiking trails, is still an attractive landscape.

The project of extending the of Castle Strünkede in Herne to just behind the Ruhr-University Bochum leading rail -line U35 of BOGESTRA has not been realized due to discussions about a nature-friendly route guidance and because of different track widths of the trams in Witten. Plans to extend line 310 from Heven to the Kemnade leisure center have been rejected as part of the integrated overall traffic planning. The Kemnader See is currently being accessed from Bochum and Hattingen by bus line 350. Bus line 320 runs from the Witten side and ensures direct connections to Herbede , Durchholz , Sprockhövel as well as to Witten city center, to Witten main train station and Witten-Annen Nord train station . On weekdays the 320 also connects the lake with the Ruhr University. Line 375 runs continuously from Witten through the Lottental to the university. In addition, this line is reinforced by the 376 every Sunday and public holiday from May to the beginning of October.

Freetime activities

The MS Schwalbe II is one of the passenger ships on the lake

A small part of the lake is also used for sailing boats, but the regatta channel is regularly clogged with sediments. When surfing, be careful not to swallow the Ruhr water, diarrhea and other illnesses are at risk. For this reason, swimming in water is not recommended. The sports institute of the Ruhr University offers its students a variety of rowing boats. A pedal boat rental for visitors looking for local recreation rounds off the offer.

There are numerous leisure facilities and sights in the immediate vicinity of the lake. The leisure pool Heveney , a kite and beach sailing school , the StrandDeck Kemnade, a beach volleyball hall , a golf course and a sailing harbor are located at the beginning of the lake. Close to the weir are the Haus Kemnade moated castle (with museums), the clubhouse of a fishing club and an unofficial meeting point for kite enthusiasts . A 12 km long skater circuit, separated from the bike and hiking path and illuminated in the evening, leads around the lake. Two clubs (SFV Witten and ASV Bochum Ruhr 1935 eV) use the lake for fishing and they also issue guest cards. The fish population ranges from eel to bream , carp , roach and pikeperch .

Passenger ships also operate on the lake and the Ruhr. In Witten, the passenger ship MS Schwalbe II docks at the following locations: Bommern Uferstraße, Nachtigall colliery , Hardenstein castle ruins , Herbede lock , Herbede lake bridge and Heveney leisure pool. At the Heveney leisure pool, you can continue your journey with the Kemnade excursion boat to the weir at the lower end of the lake.

On the circular route around the lake, the tunnel opening of the Gibraltar Erbstolln is located behind the main building of the Gibraltar colliery , today's boathouse on the western bank. The Stiepeler village church , Blankenstein Castle , the Katzenstein nature reserve and the Herbede district of the city of Witten are all within walking distance of the lake . Gastronomy, two boat rentals, playgrounds, the historic part of the Ruhr Valley Railway , a weekly children's flea market and regular open-air events complete the leisure offer.

Others

During a study of the biodiversity at Lake Kemnader in 2014, 839 species of plants, animals and fungi were identified over a period of 24 hours, 35 of which are on the Red List of Endangered Species in North Rhine-Westphalia.