Ombla River Basin problem

- The river rises as akarst spring fed by groundwater replenished by Trebišnjica, which is an influent stream flowing in Popovo Polje in the immediate hinterland of the Ombla.. O Popula

Ombla River

Name: Tr n Ng c Huy n ầ ọ ề

ID student: 1253091360

1 Introduction:

O Country: Croatia

O Region: Dalmatia

O District: Dubrovnik – Neretva Country.

O Length: 0.03 km

O Basin: 600km2 (232 sq mi)

- Get information about Ombla River.

- Try to understand the problems about economy of Ombla River.

- Find out solutions to overcome these problems

2 OVERVIEW:

O General topographic feature:

- The Ombla is a short river in Croatia, northeast of Dubrovnik Its course is

approximately 30 metres (98 feet) long, and it empties into the Rijeka Dubrovačka embayment of the Adriatic Sea near Komolac in Dubrovnik-Neretva County.

- The river rises as akarst spring fed by groundwater replenished by Trebišnjica,

which is an influent stream flowing in Popovo Polje in the immediate hinterland of the Ombla The elevation difference between the river's source and its mouth is just over

2 metres (6 feet 7 inches). 

O Climate:

- The average annual air temperature is 16.5*C.

- The average annual rainfall exceeds 1500mm.

O Vegetation and soil types:

- About 90% of the whole Ombla Spring catchment is covered by

limestone

O Water use:

- More than 95% groundwater is stored in small karst fissures

- The HEPP Ombla Underground dam will be constructerd about 200m behind the existing spring outflow in the karst missif

O Population, economic and recreation:

- As of 2012, the Ombla is used as a source of drinking water for the city of Dubrovnik The water intake plant at Komolac has

a water supply capacity of 560 litres (120 imperial gallons; 150

US gallons) per second

- The Ombla has been used as a part of Dubrovnik's water

supply network since 1897, when the first contract to supply

960 cubic metres (34,000 cubic feet) of water per day was

made with an owner of watermills operating on the river

3 Econnomy of Ombla River:

- The river water becomes opaque, containing increased proportion of suspended particulate matter, three to five times a year for periods of four to five days after increased rainfall The situation is proposed to be addressed through moving of the intake plant to a higher elevation during construction of a proposed

Ombla Hydroelectric Power Plant (HPP)

- The new water intake is planned to be constructed at 55 metres (180 feet) a.s.l

[24] These changes are expected to improve the quality of the drinking water,

and to increase the water supply capacity to 1,500 litres (330 imperial gallons;

400 US gallons) per second

- Average volume of water diverted to the water supply network varies

considerably by month, peaking during summer tourist seasons In August

2008, daily volume of water taken from Ombla for the water supply network averaged at 23,419 cubic metres (827,000 cubic feet)

-  In 2008, the annual daily volume of the water diverted averaged 17,750 cubic metres (627,000 cubic feet)

4 Conclusion remarks:

O Solutions:

- The possibilities for overcoming karst system complexity can be found in close co-operation between hydrology and hydrogeology

- Understanding of the deep and long-lasting mutual relationship between human activities and natural processes in karst

- In order to achieve their real sustainable development, it’s necessary to fill in the gaps which remain in the understanding of hydrological and ecological behavior

O  "Rijeka Dubrovačka" City of Dubrovnik Tourist Board Retrieved 21 June 2012

O  Dražen Lovrić; Darko Alfirev (March–April 2012). "HE Ombla" [Ombla

Hydroelectric Power Plant] (PDF). HEP Vjesnik (in

Croatian) 25 (254-255/294-295): 3. ISSN 1332-5310 Retrieved 22 June 2012

O  Božena Tušar (2008). "Vodoopskrba u Dubrovniku

" [Water supply in Dubrovnik](PDF). EGE (in Croatian) (Energetika marketing

d.o.o.) (4). ISSN 1330-0628 Retrieved 22 June 2012

O Dinarida

" [Geology (and hydrogeology) of karst – Examples of development of karst in t

he

Dinarides] (PDF) (in Croatian). University of Zagreb, Faculty of Science,

Geology Department Retrieved 28 January 2012. (Croatian)

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