Falkenhagener See
| Falkenhagener See | ||
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Aerial photo of Falkenhagen (view from northwest) You can see the Falkenhagener See, at the top right the Neue See and below the Vogelinsel |
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| Geographical location | in Falkenhagen , district of Falkensee ( Havelland , Brandenburg ) | |
| Tributaries | no natural influx | |
| Drain | no natural drainage | |
| Places on the shore | Falkensee | |
| Data | ||
| Coordinates | 52 ° 34 '24 " N , 13 ° 7' 19" E | |
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| Altitude above sea level | 30 m | |
| surface | 44 ha | |
| length | 2.2 km | |
| width | 250 m | |
| volume | 890,000 m³ | |
| scope | 4.97 km | |
| Maximum depth | 3.2 m | |
| Middle deep | 1.7 m | |
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particularities |
Source:, Depth indications: |
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The Falkenhagener See is a lake in Falkenhagen , a district of Falkensee near Berlin in Brandenburg . The smaller New Lake is right next door . While the Falkenhagener See dates from the last ice age, the Neue See is the remnant of a sand pit that was dug in 1934 for the construction of a railway line. They are connected to one another and form a closed inland body of water with no natural connection to other surface waters.
The two lakes are in a nature reserve . They have a certain economic importance due to the inn on the bank, but there is no direct commercial use of the waters. At the beginning of the 1990s, the Falkenhagener See was rehabilitated; the water level that tends to be too low is constantly being compensated for by water from the Havel Canal .
geography
The Falkenhagener See is the largest body of water in Falkensee. It lies with the New Lake on the northeastern edge of the city. To the north is the Spandau Forest .
The Falkenhagener See has an elongated bent shape, the Neue See is triangular. The smaller, artificially created New Lake is located south of the other; the two bodies of water are separated by a one-kilometer-long and ten-meter-wide dam. The dam runs from north-west to south-east. The two lakes are connected by a narrow channel.
In the south-east there is a part which is now separated from Falkenhagener See by a road (Humboldtallee), called "Fauler See". This part is increasingly silting up and can only be recognized as a swamp area.
Both the Faule See and the Falkenhagener See are referred to as "Alter See", depending on the work.
The lake is located in the Nauen - Brieselang - Krämer nature reserve . To protect the flora and fauna, many leisure activities are restricted.
The bird island in the west of the lake is only surrounded by a strip of water about three meters wide. This ditch was created artificially and is partly no longer passable for boats due to silting, fallen trees and dense reeds. Access to the island is closed to protect wildlife and because of the swampy subsoil.
| Falkenhagener See | New lake | total | |
|---|---|---|---|
| Water surface (in ha ) | 44.0 | 11.9 | 55.9 |
| Volume (in m³ ) | 890,000 | 250,000 | 1,140,000 |
| Shoreline (in m ) | 4,970 | 1,690 | 6,660 |
Origin and history
The area of the two lakes belongs to the Rhin and Havelländischen Luch, which belongs to the Warsaw- Berlin glacial valley . The Falkenhagener See was formed in the Frankfurt stage of the last ice age as an ice age glacier channel.
The Neue See is a former sand pit that was created between 1934 and 1935 when the Deutsche Reichsbahn expanded the S-Bahn route . After the completion of the route, the pit was filled with groundwater and later connected to Lake Falkenhagen.
Until 1919 the Falkenhagener See belonged to the Ribbeck family , who became known far beyond Brandenburg through the stories of Theodor Fontane . Falkenhagen is also mentioned in Fontane's stories. The community later bought the lake back.
In the 1920s, the settlement of the shore began. In order to be able to sell even more water plots, the ditch was built around today's Vogelinsel, but the settlement remained incomplete there as well as on the east bank. Many of the houses date from the early days, but there was renewed construction after the fall of the Wall , when many newcomers settled there.
Until the end of the 1950s there was a public bath on the south bank of the Falkenhagener See. After it was closed for hygienic reasons, the two lakes are no longer listed as bathing lakes.
In 1957 the Deutsche Reichsbahn handed over the Neuer See to the community of Falkensee (today the city of Falkensee). As can be seen from the aerial photographs, the breakthrough between the lakes - an approximately three-meter-wide connecting canal - was dug between 1953 and 1966.
In the area of the Faulen See there is peat that was cut until the 1970s.
The former fishing casino , which was located on the site of the old outdoor swimming pool, burned down completely on the night of January 6, 2007.
use
The use of motor and sailing boats is prohibited, but boats without a motor drive are allowed to sail on the lake for a fee. Pedal boats can be borrowed from the Quo Vadis restaurant . At the Falkenhagener See around 70 piers provide access to the water, at the Neuer See there are neither jetties nor piers.
Bathing is not officially allowed, as the limited visibility and difficult access to the bank make it very difficult to rescue drowning people. However, with the tacit approval of the city administration, there is still plenty of bathing. In Falkenhagener See, swimming is only possible from a boat, there is a small beach at Neuer See.
In winter, the lake often freezes over completely and is used for ice skating, skiing and ice hockey.
The lake is irrelevant as a traffic route and for commercial fishing; no drinking water is obtained.
The shore of the lake is not for sale and belongs to the city of Falkensee. Nevertheless, around half of the bank is only used by the direct neighbors like part of their property. The other part of the bank can be walked on: around the Neuer See and on the east bank of the Falkenhagener See.
Sights and buildings
At the western tip of the lake (to be more precise, to the west of the moat around Vogelinsel) is the “Red Villa”, an old brick villa that has been vacant for a long time. At that time it was a restaurant and bottled beer shop, also called the “Max and Moritz House” after the two “boys” on the gable. The Rote Villa is a well-known house locally, the bus stop there is also called “Falkensee, Rote Villa”.
The Madagascan embassy and the ambassador's residence are located in the Beuge on the west bank of the lake on a water plot in the promenade.
ecology
fauna
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There are many birds on the protected bird island, including gray herons and kingfishers .
In addition, the lake is swans , grebes , Stock- and Pochard , Moorhen , reed bunting , coots , throttle warblers and reed warblers settled that can nest in the broad reed belt.
Also, grass snakes belong to the shore and lake-dwellers.
The fish population is sufficiently high, especially pike , pikeperch and carp , but eels and catfish also populate the lake. The fish stocks are regularly replenished by the anglers' association.
flora
The bank is almost continuously surrounded by a dense belt of reeds that are around five meters wide . Water lilies can sometimes be found in vacant spots . On the bank there are mainly willows , alders and other trees that can cope well with very moist soil.
sediment
Under the water layer, which was once one meter and now three meters, there is a muddy sediment that is up to twelve meters deep (up to 15 meters before the remediation). The mean thickness of the sediment is 5.3 meters. The sediment can be divided into different zones according to the size and strength of the particles:
“The sediments are referred to as organogenic detritus muds with a fine to medium structure, [which] have a distinct [distinct] odor of hydrogen sulfide (H 2 S) (MLTU 1990, LUA, Dept. W). From a sediment depth of 3-5 m, brown leather appears in the form of mudden- like horizons. With increasing depth, gray clay, sand and lime muds are increasingly found. Despite the young age, organogenic detritus sludge containing H 2 S was also found in the course of this investigation in the New Lake . "
Water quality
The water quality has repeatedly been a problem in the lake, so a renovation was carried out in the 1990s. In 1930 - just a few years after the settlement - a fish death was reported for the first time. The bathing establishment was closed at the end of the 1950s for hygienic reasons. In 1976 fish and water birds died out due to botulism .
Today, the water quality allows bathing - as mentioned above - without hesitation. However, bathing is not allowed due to the low visibility. The maximum depth of vision is 80 centimeters, in summer it is sometimes less than 20 centimeters, and it is usually not possible to see the bottom. A goal of the renovation - a visual depth of at least one meter - was not (permanently) achieved. The water in the lake cannot be used as drinking water.
Phytoplankton is responsible for the increased turbidity of the water in summer.
The water quality was affected in the following ways:
- The low water levels (in 1972 at 29.42 meters, corresponding to less than 0.5 meters water depth) put a great strain on the lake's ecosystem,
- the water introduced from the Havel Canal for compensation was heavily contaminated with heavy metals and chemicals from industry and agriculture during the GDR era ,
- in the east of the lake there was a pig fattening, the soil pollution of which by manure also affected the lake,
- instead of sewer pipes, the residents had cesspools in the gardens, which were emptied regularly but were unfortunately not always tight enough
- Submerged plants (especially reeds) and leaves from the trees on the shore add new organic material to the lake every year.
In the meantime, the level has been maintained quite well, the water in the Havel Canal is significantly better, the pig fattening has been closed, Falkenhagen is completely connected to the sewage system and the lake has been rehabilitated (see next section). However, the exposure to organic material has increased due to the increased protection of the flora.
Redevelopment
The aforementioned pollution made it necessary to rehabilitate the lake. In 1991, the state of Brandenburg launched a funding program to restore water bodies in need of rehabilitation. From September 1991 to the end of April 1997, the Falkenhagener See was renovated with funds from the funding program. The mud was dredged with the help of a dredger. Around 553,000 cubic meters of wet sludge were pumped; a total of around one million cubic meters of filtrate was treated. After dredging, ferric chloride was added to the water to precipitate the phosphate and let it sink to the bottom (the phosphate is bound in the remaining sludge).
The sludge was examined, classified as safe and then taken to nearby fields. The mud was a welcome fertilizer for the sandy Brandenburg soil. The result of the renovation was a water depth of three meters instead of half a meter, a reduction in the phosphate concentration in the water by around 85% from 0.19 to 0.03 milligrams per liter and an increase in the visibility depth to over a meter (not permanent).
This means that the formerly hypertrophic Falkenhagener See is now considered mesotrophic. The costs amounted to 22,670,064.95 DM (adjusted for inflation around 16,260,000 euros) and were therefore around 6% below the estimated 24 million DM. Only the Falkenhagener See was dredged, not the Neue See. However, due to the mixing of the water and the second remediation step, the water quality in the two lakes is now quite similar.
Hydrology
| year | Additional water (in cubic meters) |
origin |
|---|---|---|
| Source: | ||
| 1991 | 100,000 | Havel Canal |
| 1992 | 980,000 | Havel Canal |
| 1993 | 340,000 | Havel Canal |
| 1994 | 130,000 | Havel Canal |
| 1995 | 190,000 | Havel Canal |
| 1996 | 570,000 | Havel Canal |
| 1997 | 440,000 | Havel Canal |
| 1998 | 1,100,000 | Havel Canal |
| 1999 | 920,000 | Havel Canal |
| 2000 | 1,060,000 | Havel Canal |
| 2001 | 870,000 | Havel Canal |
| 2002 | 160,000 | Havel Canal |
| 2003 | 1,090,000 | Havel Canal |
| 2004 | 830,000 | OWA: 440,000 Havel Canal: 390,000 |
| 2005 | 898,000 | OWA: 150,000 Havel Canal: 748,000 |
| 2006 | 1,431,000 | OWA: 150,000 Havel Canal: 1,281,000 |
| 2007 | 300,000 | Havel Canal |
| 2008 | 730,000 | Havel Canal |
| 2009 | 1,400,000 | Havel Canal |
| 2010 | 1,090,000 | Havel Canal |
| 2011 | 710,000 | Havel Canal |
| 2012 | 780,000 | Havel Canal |
| 2013 | 915,000 | Havel Canal |
| Average | 740,000 | |
There are three official staff levels in Falkenhagener See. One is in the northwest part of the trench around Vogelinsel near the Rote Villa , others can be found at the passage between the two lakes and on a publicly accessible footbridge behind Haydnallee 11.
An attempt is made to reach a water level of 30.60 meters above sea level . The minimum level should be 30.40 meters.
The bottom of the puncture between the two lakes is around 30.45 meters.
Apart from the connection with the groundwater, there are no natural inflows and outflows. Since the lake loses a lot of water every summer through evaporation and seepage, water is added accordingly every year.
The water comes from the Havel Canal near Schönwalde and is transported to the lake through an underground pipe. The line was built during the GDR in the 1970s. The water runs by itself, but the flow is increased by a pump at the point of extraction (Docklenz pump, type Umy 300).
The water is pumped out at kilometer 7.9 (the intake pipe could not be located exactly during dives and is probably under the stone packings) on the left bank of the Havel Canal and close to the north-western end of the lake via a four-kilometer steel pipeline (diameter: 600 mm) the level at the Rote Villa.
In the meantime, water from the "Osthavelländische Trinkwasserversorgung und Abwasserverarbeitung GmbH" (OWA) has also been used for feed-in, which has been discontinued for cost reasons.
Others
The 652 bus of the Havelbus Verkehrsgesellschaft goes around the lake and to the Falkensee train station .
There are nine fishing clubs on the shores of Falkenhagener See: seven in the lake promenade, one in Schubertallee and one at the Rote Villa.
A long-standing controversial topic of Falkensee local politics is the northern bypass, which is supposed to lead past the eastern end of the lakes. FDP , CDU , the SPD and the citizens' initiative Pro Northern bypass “Human-Traffic-Life” support the northern bypass. Greens and the citizens' initiative Schöne Falkensee e. V. criticize the draft as too expensive, as ineffective to counterproductive for traffic management and harmful to the environment, especially for the lakes.
See also
Web links
- bisf.eu - “Citizens' Initiative Schöne Falkensee e. V. “ - Critic of the northern bypass
Individual evidence
- ↑ a b c d Green Area Office Falkensee, 2007 and 2014.
- ↑ a b c d e f g h i Wilhelm Ripl, Michael Feibicke, Bernd Koppelmeyer: Management concept for the Falkenhagener See and for the Neuer See (Havelland district) - final report . Ed .: GFG Gesellschaft für Gewässerbewirtschaftung mbH [TU Berlin]. Report 47 G 96, October 1996 (on behalf of the City of Falkensee).
- ↑ a b City Council Assembly Falkensee (ed.): The new version of the user regulations for the Falkenhagener -, the Neuer See and their bank areas . Decision 107/45/03. Falkensee June 25, 2003 (adopted unanimously with 27 votes in favor).
- ↑ Rosenkranz 1991, Markstein et al. 1992, CGI 1993, quoted from Ripl, p. 3
- ↑ Dietmar Zielke: Sad end - angler's casino burned down. (PDF; 2.1 MB) In: Falkenseer Kurier. January 6, 2007, p. 2 , accessed October 6, 2011 .
- ↑ Engineering office Dr. Fechter GmbH (Hrsg.): Final report on the renovation measure Falkenhagener See . Report 97.310.041. Falkensee May 29, 1997.
- ^ To the interest group Ruhiges Falkensee. CDU Falkensee, September 18, 2008, accessed on October 6, 2011 .
- ↑ Heiko Müller: Northern bypass will come. SPD Falkensee, February 6, 2007, accessed October 6, 2011 .
- ↑ Northern bypass. (No longer available online.) Green Havelland, Havelland district association, Falkensee local association, formerly the original ; accessed on January 14, 2016 . ( 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.
