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Wikipedia / Drava

The Drava or Drave (, ; ; ; ; ), historically known as the Dravis or Dravus, is a river in southern Central Europe. With a length of (441 miles), or (450 miles), if the length of its Sextner Bach source is added, it is the fifth or sixth longest tributary of the Danube, after the Tisza, Sava, Prut, Mureș and likely Siret. The Drava drains an area of about 40,154 square kilometers (15,504 sq. mi.). Its mean annual discharge is seasonally (650 cu. yd.) per second to (880 cu. yd.) per second. Its source is near the market town of Innichen, in the Puster Valley of South Tyrol, Italy. The river flows eastward through East Tyrol and Carinthia in Austria into the Styria region of Slovenia. It then turns southeast, passing through northern Croatia and, after merging with its main tributary the Mur, forms most of the border between Croatia and Hungary, before it joins the Danube near Osijek, in Croatia.

Name

In ancient times the river was known as Dravus or Draus in Latin, and in Greek as Δράος and Δράβος. Medieval attestations of the name include Dravis ( AD 670), Drauva (in 799), Drauus (in 811), Trauum (in 1091), and Trah (in 1136). The name is pre-Roman and pre-Celtic, but probably of Indo-European origin, from the root *dreu̯- 'flow'. The river gives its name to the dravite species of tourmaline.

Carpis

The Carpis (Greek: Κάρπίς) was a river which, according to Herodotus, flowed from the upper country of the Ombricans northward into the Ister (Danube), whence it has been supposed that this river is the same as the Dravus.

Geography

The Drava (along with one of its tributaries, the Slizza) and the Spöl are the only two rivers originating in Italy that belong to the Danube drainage basin. Its main left tributaries (from the north) are the Isel (contributes 39 m3/s), the Möll (25 m3/s), the (22 m3/s), the Gurk (30 m3/s) and the Lavant (12 m3/s) in Austria, and the Mur (166 m3/s) near Legrad at the Croatian–Hungarian border. Its main right tributaries (from the south) are the Gail (45 m3/s) in Austria, the Meža (12 m3/s) and Dravinja (11 m3/s) in Slovenia, and the Bednja (? m3/s) in Croatia.

Country

Length (km)

Catchment area (km2)

Mean flow (m3/s)

Italy

10.6

354 (0.9%)

4

Austria

254.7

(55.2%)

280

Austria–Slovenia

4.2

border

Slovenia

117.7

4662 (11.6%)

292

Slovenia–Croatia

23.3

border

Croatia

166.4

6822 (17.0%)

544

Croatia–Hungary

133.0

border

Hungary

0

6154 (15.3%)

544

Total

709.8

(100%)

544

Mean discharge is for the last station in the country mentioned in the source.

Course

The sources of the Drava are located at the drainage divide between the market town of Innichen/San Candido and neighbouring Toblach/Dobbiaco in the west, where the Rienz River rises, a tributary of the Adige/Etsch. At Innichen itself the 16+ km (10 mile) , originating near the Sextener Rotwand, joins the ~2km (1¼ mile) long source creek. The river then flows eastwards and after 8 kilometres (5 miles) crosses into East Tyrol in Austria. At Lienz it flows into the Isel, sourced from the glaciers of the Venediger and Glockner Groups. The Isel (average discharge 39m3/s) is almost three times larger than the Drava (14m3/s) where they meet and, starting from the source of its tributary under the Rötspitze, the Isel (ca. 64km; 40 miles) is also longer than the combined Drava and Sextner Bach (ca. 60km; 35 miles) to that point.

The river then flows east into Carinthia at Oberdrauburg. The river separates the Kreuzeck range of the High Tauern in the north and the Gailtal Alps in the south, passes the Sachsenburg narrows and the site of the ancient city of Teurnia, before it reaches the town of Spittal an der Drau. Downstream of Villach, it runs along the northern slopes of the Karawanks to Ferlach and Lavamünd.

The Drava passes into Slovenia at Gorče near Dravograd, from where it runs for via Vuzenica, Muta, Ruše, and Maribor to Ptuj and the border with Croatia at Ormož.

The river then passes north of Varaždin, after which it receives the Plitvica and Bednja from the right, and then Mura at the border with Hungary. It continues as a largely border river towards the southeast, receiving and from the right. It passes the city of Barcs in Hungary from the south. It starts to be navigable, for about in Croatia, from the confluence of the Čađavica to its mouth. It passes Belišće from the north, receives the Karašica from the right, and then passes the city of Osijek from the north. Afterwards, it enters the Kopački Rit wetland and merges into the Danube from its right.

The hydrological parameters of Drava are regularly monitored in Croatia at Botovo, Terezino Polje, Donji Miholjac and Osijek.

Discharge

The Drava's mean annual discharge (Q – m³/s) at Drávaszabolcs (Hungary, 77.7 rkm). Period from 1995 to 2025.

Year

Q

Year

Q

1995

479

2011

442.4

1996

598

2012

528.3

1997

437

2013

638.5

1998

513

2014

714.9

1999

588

2015

459.2

2000

549

2016

269.7

2001

464

2017

359.7

2002

410.6

2018

446.4

2003

348.8

2019

259.8

2004

501.6

2020

535.5

2005

474.1

2021

478.4

2006

326.7

2022

319.1

2007

338

2023

636

2008

483.5

2024

628.2

2009

627.9

2025

369.8

2010

633.4

2026

Hydroelectric power plants

Currently, there are 22 hydroelectric power plants on the Drava. The power plants are listed beginning at the headwaters:

Dam

Nameplate capacity (MW)

Annual generation (Mio. kwh)

Amlach power station

60

219

Paternion

24

95

Kellerberg

25

96

Villach

25

100

Rosegg-St. Jakob

80

338

Feistritz-Ludmannsdorf

88

354

Ferlach-Maria Rain

75

318

Annabrücke

90

390

Edling

87

407

Schwabeck

79

378

Lavamünd

28

156

Dravograd

26.2

142

Vuzenica

55.6

247

Vuhred

72.3

297

Ožbalt

73.2

305

Fala

58

260

Mariborski Otok

60

270

Zlatoličje

126

577

Formin

116

548

Varaždin

86

476

Čakovec

75.9

400

Dubrava

84

The Drava is one of the most exploited rivers in the world in terms of hydropower, with almost 100% of its water potential energy being exploited. As the region of the river is a place of exceptional biodiversity, this raises several ecological concerns, together with other forms of exploitation such as use of river deposits.

References

Bibliography

  • DrauDrava - old river and new sounds

  • Condition of Drava in various locations in Slovenia:

  • Črneče - graphs, in the following order, of water level, flow and temperature data for the past 30 days (taken in Črneče by ARSO)

  • Ptuj - graphs, in the following order, of water level, flow and temperature data for the past 30 days (taken in Ptuj by ARSO)

  • Borl - graphs, in the following order, of water level, flow and temperature data for the past 30 days (taken in Borl by ARSO)