Ogosta reservoir
| Ogosta reservoir | |||||||||
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| Coordinates | 43 ° 22 '31 " N , 23 ° 10' 56" E | ||||||||
| Data on the structure | |||||||||
| Lock type: | Earthfill dam | ||||||||
| Construction time: | 1966-1986 | ||||||||
| Height of the barrier structure : | 60 m | ||||||||
| Height above valley floor: | 135 m | ||||||||
| Height above the river bed : | 186 m | ||||||||
| Height of the structure crown: | 195 m | ||||||||
| Crown length: | approx. 970 m | ||||||||
| Crown width: | approx. 50 m | ||||||||
| Data on the reservoir | |||||||||
| Altitude (at congestion destination ) | 1223 m | ||||||||
| Water surface | 23.6 km² | ||||||||
| Reservoir length | 6.26 km | ||||||||
| Reservoir width | approx. 2.6 km | ||||||||
| Storage space | 384 - 510 million m³ | ||||||||
| Catchment area | 948 km² | ||||||||
The Ogosta Reservoir ( Bulgarian: Язовир Огоста ) is the second largest lake and reservoir in Bulgaria after the Iskar Reservoir . The name comes from the river of the same name, which was dammed. According to the Cambridge Ancient History (CAH), the name Ogosta should be derived from the Latin Augusta .
location
The reservoir is located in northwestern Bulgaria in the Montana Oblast . At the end of the reservoir in the east, about 400 m from the dam, is the city of Montana (Bulgarian: Монтана ). That is why the reservoir is referred to in some sources as the Michajlovgrad reservoir (Bulgarian: Pезервоа Михайловград ), after an old name of the city of Montana. The reservoir is surrounded by the villages of Blagovo (Bulgarian: Благово ) in the east, Borowtsi (Bulgarian: Боровци ) in the south and Gorno Tscherowene (Bulgarian: Горно Церовене ) in the northwest. The capital Sofia is 109 km away in the south.
Hydrology
Inflow and outflow
The reservoir is fed by its main river, the Ogosta, which carries an average of 25.4 m³ of water per second. Other streams as tributaries are the Bŭrziya (Bulgarian: Бързия ), the Zlatitsa (Bulgarian: Златица ), the Turya bara (Bulgarian: Туря бара ) and the Barata (Bulgarian: Барата ), all of which flow into the lake from the south. The runoff is in front of Montana, here the Ogosta flows north to the Danube. The catchment area of the lake is 948 km².
Reservoir
The Ogosta Reservoir is the second largest lake and reservoir in Bulgaria with an area of almost 24 km². It was built for a volume of 510 million m³; due to static problems, the maximum filling volume since 1986 has been 400 million m³. The average filling volume is 384 million m³.
The dam is almost one kilometer long and about 50 meters wide at the top and is passable. However, the road on the dam is closed for safety reasons.
Water quality
Even the water of the Ogosta is heavily polluted with nitrate, so that the quality of the lake water suffers. However, swimming in the lake is possible and, according to the Bulgarian authorities, is harmless.
fauna
In 1999 the Ogosta reservoir was opened for general fishing. There are numerous species of fish in the lake. a. Carp ( Cyprinus carpio ), gables ( Carassius gibelio ), Rudd ( Scardinius erythrophthalmus ), bream ( Abramis brama ), perch ( Perca fluviatilis ), lugs ( Chondrostoma nasus ), flow barbs ( Barbus Barbus ), flow catfish ( silurus glanis ), pike ( Esox lucius ) and Mairenken ( Alburnus chalcoides ). In addition, the zebra mussel (also: Wandermuschel) ( Dreissena polymorpha ) has spread in the lake, the proliferation of which led to disturbances in the lake's ecosystem.
Building history
Planning for a reservoir off Montana began in the early 1960s. Construction began in 1966 and was completed in 1986. The dam was inaugurated on September 23, 1987 under Prime Minister Todor Schiwkow (Bulgarian: Тодор Живков ).
Two villages, Jiwowtsi (Bulgarian: Живовци ) and Kalimanitsa (Bulgarian: Калиманица ) had to be abandoned for the construction in 1979 . Depending on the water level, the church tower of the Church of the Assumption in Jiwowtsi is visible most of the time, it is on the north bank of the lake. Residents were to Montana and berkovitsa (Bulgarian: Берковица ) forcibly resettled.
The original plan was to use the water from the reservoir to irrigate large areas north of Montana between Montana and Zlatia near Lom (Bulgarian: Лом ) (180,000 hectares in total), but only half of the necessary construction work had been carried out by 1989. No further construction work has been carried out since the end of the communist era; since irrigation is no longer profitable.
Today only a tiny fraction of the planned area - in the immediate vicinity of Montana - is irrigated, but two hydropower plants located one behind the other, the Ogosta and Koscharnik plants , generate electrical energy.
Since its commissioning, the dam has been suspected of being unstable. Although the lake was designed for 510 million m³, it was never filled with more than 400 million m³ because it was feared that the dam wall would not be able to cope with the pressure. In the communist era, all opinions on this were suppressed; but since the 1990s there have been repeated indications of a lack of stability. There are also rumors of a tunnel under the dam that is contributing to the instability. In 2005 there was a further complaint due to the use of Ecoglasnost , but this was rejected as unfounded. Since then, however, entering the dam has been forbidden and there are constant police checks; allegedly out of fear of terrorist attacks. At the southern end of the dam there is a natural swimming pool with slides, pools, restaurants and a sandy beach.
Web links
Individual evidence
- ↑ Официален сайт на община Монтана - Диана, покровителка на Монтана. Retrieved April 3, 2019
- ^ John Bagnell Bury et al .: The Cambridge Ancient History: the Augustan Empire ; Cambridge University Press, 1934, reprinted 1952.
- ↑ Penin, Rumen: Природна география на България ( Natural Geography of Bulgaria ) Sofia, Bulvest 2007. ISBN 978-954-18-0546-6 . P. 263.
- ↑ Homepage of the City of Montana www.montana.bg
- ↑ Teodora Stoyanowa: "Ecological status of Ogosta" in "Acta Zoologica", 2014.
- ↑ Kaloyan Belopolsky in the newspaper "Standard Nachrichten" of August 10, 2001 (Калоян Белополски: Язовир "Огоста" бъка от риба, в-к "Стандарт", 10 август 2001)
- ↑ Teodora A. Trichkova: Journal of Natural History 42; February 2008.
- ↑ в. Септемврийско слово ( Speeches in September ) Issue 113, September 24, 1987.
- ↑ a b c ОБЩЕСТВО И ПОЛИТИКА. Retrieved April 3, 2019