Karst Groundwater Use in the Carpathian-Balkan Region
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Sustainable development and regulation of karst aquifers Dr Zoran Stevanovic, Prof. University of Belgrade, Serbia FMG, Department of Hydrogeology [email protected] “Linking waste water management to ICZM and IWRM with emphasis on karstic coastal areas" Split, Croatia, 19-22 March 2012. Topics Importance of karst aquifers and their utilization in SEE Groundwater balance and resources assessment in karst Storativity as the main factor in regulation of karst aquifers Sustainable use and regulation of karst waters 1. Importance of karst aquifers and their utilization in SEE Karst phenomena and their distribution Margat et al. Alpine orogenesis geostructures The geology of the region is complex. For most of the Mesozoic period, the Thetis Ocean covered this area, whereas during Tertiary its central part was exposed to the Alpine orogenesis when the majority of today’s mountains were uplifted and folded. The homeland of “classical karst”. Mesozoic carbonates are spread out in the central part of the region arch and its terminal parts: In the western and southern adjacent areas – Apennines, Alpides, Dinardes, Pindes and Hellenides as well as Carpathian – Balkan region. Along with alluvial groundwater and surface water from the reservoirs, the water from the karstic springs is the main source of water supply in the region. Tapping large springs is the traditional method of water supply in the region but the main concern is their unstable discharge regime. SEE Europe • In the Alpine orogenic belt the karstified carbonate rocks are either dominant, as in the Dinarides, or widely distributed, as in the Carpathian-Balkans, Hellenides or Pindes. • Concerning karstic groundwater resources, this region is by far the richest in all of Europe. • Some areas, such as southern Montenegro where the average specific yield is over 40 l/s/km2, are characterized by a very intensive water balance. • In several countries in the region water supply from karstic aquifers prevails. Karst in Turkey Courtesy of G.Gunay There are several large cities in SEE with populations of over a half of million that depend on karst aquifers and their discharge regimes. Among them are the five capitals Vienna, Tirana, Skopje, Sarajevo, and Podgorica, whereas some other big cities such as Banska Bystrica, Niš, Craiova, Constanza, Thessaloniki use either only karstic waters or, in case of insufficient discharge, combine them with water from other sources. Main advantage and disadvantage of tapping karst aquifers (+) The exploration of karst groundwater is more costly and less predictable in terms of final outcomes, but the extraction is regularly much cheaper and environmentally friendly than surface water use. (-) Due to the unstable regime of the karstic sources, the main problem for most of the waterworks is to ensure water supply during recession periods. Tapping karstic springs - Traditional way of water supply since Roman time An ancient art in the area. We all learn from Roman time experiences 11 long aqueducts delivered more than 13 m3/s of water to Rome from distances ranging from 16-91 km. Several water supply systems from that time are completely reconstructed but still use the same springs and pipeline routes. Vienna water supply Water supply system is more than 130 years old. It consists of two major gravity pipelines 150 and 180 km long, and one reserve system of Ranney wells (shaft with horizontal drains) in alluvium. First Viennese mountain spring pipeline is tapping water from Schneeberg, Rax and Schneealpe mountains and second pipeline from Hochschwab Mt. The total catchment is around 600 km2. The long concrete tunnels and channels provides daily 400.000 m3 or 4,6 m3/s in average, for some 1,5 million of inhabitants. Total length of public pipelines: 3,263 km Total number of house mains: 100,832 Maximum daily consumption (June 12, 2003): 531,970 m3 Kaiserbrunn spring (Rax Mt, Vienna), the masterpiece of design and intake quality from the 19th Ct Sarajevo and Podgorica water supply Vrelo Bosne springs. The discharge of this group of springs that drain rich Triassic aquifer of the Igman Mt. is in the range of 1.4 – 24 m3/s Skadar basin is one of European’s largest GW reservoirs Mareza source: Q = 2 - 10 m3/s; Ascending springs at the contact of limestones and fluvial - glacial sediments At 25 m a.s.l. Only chlorination applied Tirana water supply Albanian capital Tirana gets its water in part from the source that drains karstic aquifer at a nearby Mali me Gropa highly karstified plateau (Upper Triassic - Lower Jurassic in age). The karst springs Selita (Q = 0.24 – 0.86 m3/s) and Shemria (Q = 0.45 – 1.50 m3/s) are in Selita use since Mid of XX Ct., while Spring the third spring Buvilla issues from the Upper Cretaceous dolomite formation of Dajti Mountain massif (and flow into downstream constructed reservoir). Groundwater is low mineralized and of good quality. Natural conditions and unpopulated catchments are in favor of Courtesy of R.Eftimi sanitary protection. Skopje water supply The capital Skopje gets most of its drinking water from karstic aquifer. Rasce spring is situated on the Vardar River bank upstream of the town. The spring appears from the Zeden massif consists of the marbles, but the tracing tests and isotopic analyses confirmed that only 30% of the water comes from those rocks. The majority of Rasce water is from porous aquifer that exists in the upper-positioned Polosko polje and from the percolated Vardar water lost in the upstream river sections. The discharge regime is relatively stable; the mean flow is 2.5 m3/s. Dumanli spring / Turkey The enormous Dumanlı spring in the Mediterranean region of Turkey already submerged by the year 1982 by about 120 m head produced by the Oymapınar Reservoir. The spring contributes one third to the annual discharge of the Manavgat River, that will be dammed at Oymapınar. The mean discharge of the spring is estimated at about 50 m3/s; Courtesy of G.Gunay Bulgarian karstic aquifers In Paleozoic marbles; in Triassic carbonate complex; In Upper Miocene limestones. Ex. Iskrets spring: 35 km from Sofia, Q=0.1-15 m3/s. Extreme max 56 m3/s 16000 14000 12000 10000 8000 6000 Discharge,l/s 4000 2000 0 1963-1997 year Romanian karstic aquifers 1.Carpathian Orogen karst type, 2. the North Dobrogea karst type, 3. the Platform karst type and the 4. Carpathians post-tectonic cover karst type (by Oraseanu) Despite non-extensive outcrops of the karst in comparison with the large territory (some 4%), the karstic aquifers are richest in water and most prospective Water supply of Constanza, Craiova… The largest springs: Izvarna (Q Min / Max = 1.0 / 2.5 m3/s, tapped for 115 km far Craiova); Cerna (F = 85km2; Q Min / Max = 0.5 / 10 m3/s) Courtesy of A.Iurkiewicz Serbian karstic aquifers Dinaric and Carpathian’s karst sources provide about 35% of the drinking water to the population in western and eastern part of the country. The largest springs: Mlava (Q Min / Max = 0.3 / 14 m3/s); Perucac (Q Min / Max = 1.3 / 6.2 m3/s) Karstic sources and water shortage problems along the coast Adriatic and Ionian coastal tourist areas strongly depend on groundwater from the karst. There, besides the problem of water shortage during the recession period (summer-autumn), water pollution or salty water intrusion often means that local water and economy sectors cannot be expanded and properly developed. Very important springs supplying Croatian coast such as Jadro (Split), Ombla (Dubrovnik), islands and smaller tourist resorts. Timavo, with an average discharge rate of 30 m3/s, has been tapped to supply water to Trieste. Rizana near Koper is the main source for supplying water to the Slovene 3 3 coastal zone. Its average discharge is 4.3 m /s (Qmin= 0.03 m /s). The Zvir group of springs were tapped at the end of the 19th century to supply water to Rijeka, the largest Croatian port. The discharge varies between 0.6 and 3.0 m3/s (Biondic and Goatti 1984). Jadro Spring is the main source for the water supply of Split. The average minimum discharges of Jadro during the recession period are 3– 5 m3/s, while maximum discharges are often over 50 m3/s (Bonacci 1987). Ombla Spring is the largest permanent karstic spring in the South Adriatic. It supplies the city of Dubrovnik. Qmin = 2.3 m3/s Montenegro coastal springs Q min:max 1:100.000 ?! Thessaloniki combine system of water supply The springs Aravissos are drain the karst aquifer of Paiko Mountain (some 50 km West from the city). During the period 1994 – 2007 annual amount of water distributed to the city varied from 27 x 106 m3 – 55 x 106 m3. Due to increased demands (240.000 m3/day) groundwater abstraction from the porous aquifer system of the Thessaloniki - Axios basin is intensified, while since 2003 the water of Aliakmon river also partly supply the city (Spachos et al. 2006) 2. Groundwater balance and resources assessment in karst Balancing GW is not an easy task ! Invisible, even had been declared as “misterious” resource! “…so secret, occult and concealed that an attempt to administer any set of legal rules in respect to it, would be involved in uncertainity” Supreme Court of Ohio (1861) (courtesy of T. Cincaid) Litospheric groundwater ~ 23 x 106 km3 Half of them are fresh water, the rest mineralized or hydrothermal dissolutions In active water cycle ~ 4 x 106 km3 27 Balancing GW quantity (reserves) Methodologies are variable, depend on aquifer Aquifers classification based on porosity: 1. Porous (Integranular) 2. Karst (Dissolution) 3. Fissured (Fractured) 4. Complex Aquifers classification based on HD condition: 1.