Čierna voda

Geological structure beneath the water

Which rock lies beneath the water line (Geological Map of Slovakia 1:50,000), how old it is, how thick the Quaternary cover is and in which tectonic unit the water flows. The bedrock decides the hardness of the water, the bottom, the turbidity after rain and the abundance of springs.

The points follow the water line (for a stream and a basin, fishing district after fishing district). The strip is a cross-section by distance, not a map; the width of a section corresponds to the number of points.

• River alluvium100%SR 72 %

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River alluvium: Gravelly and sandy bottom and floodplains; the water is replenished from groundwater in the alluvium.

Geological age of the rocks

• Quaternary100%

Most common rock units

Quaternary cover

• fluvial sediments of floodplains100%SR 68 %

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• Typical thickness of the Quaternary cover30m

• 30 – 4050%SR 1.5 %
• 20 – 3050%SR 1.3 %

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Tectonic division

• NEOALPÍNSKE TEKTONICKÉ ŠTRUKTÚRY ZÁPADNÝCH KARPÁT100%SR 84 %

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Neotectonic units

• negative unit (lowland plains and basins, neotectonic depressions)56%SR 13 %
• positive unit (lowland hills)44%SR 14 %

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Direction of neotectonic movements

• small subsidence56%SR 8.8 %
• small uplift33%SR 7.7 %
• very small uplift11%SR 6.4 %

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Regional geological division

• intramontane basins100%SR 44 %

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Regional geological division (subunits)

• East Slovak Basin100%SR 7.6 %

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Engineering-geological districts

• region of alluvial-plain deposits100%SR 15 %

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Engineering-geological formations

• formation of Quaternary sediments100%SR 71 %

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Susceptibility of the area to slope deformations

• Region of stable areas100%SR 95 %

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The map covers 8 of 9 points on the water line.

Hydrogeology: aquifers and groundwater

Streams and rivers are fed by groundwater. Hydrogeological maps show in which rocks the water is stored, how permeable they are and what the water in them is like. The data come from ŠGÚDŠ maps, not from measurements at a particular water.

Aquifer rocks (hydrogeological map 1:200,000)

• Gravel88%SR 52 %
• Sand13%SR 3.9 %

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Aquifer type

• Menšie zvodnence s medzizrnovým alebo puklinovým typom priepustnosti alebo oblasti s takmer žiadnymi množstvami podzemnej vody (Gravel)88%SR 22 %
• Menšie zvodnence s medzizrnovým alebo puklinovým typom priepustnosti alebo oblasti s takmer žiadnymi množstvami podzemnej vody (Sand)13%SR 2.4 %

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Main hydrogeological region

• Neogene of the East Slovak Plain between Laborec and Čierna Voda89%SR 0.0 %
• Quaternary of the lower part of the streams Uh, Laborec, Ondava and the right side of Latorica11%SR 0.0 %

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Geothermal groundwater bodies

• Trebišov Basin50%SR 0.9 %
• Humenné Ridge50%SR 4.4 %

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Surface water chemistry according to the atlas

Modelled composition of the water in the area the fishing district line runs through. The rasters of the Geochemical Atlas of Slovakia (surface waters) are an interpolation of measurements in sampled streams, so they show the typical background of the area, not a measurement in a particular stream.

Ionic composition of the water

Water type by dominant ions: Ca–Mg–HCO₃

Shares are in equivalents, the usual way of comparing the composition of waters.

Major ions

• FluoridesF0.215 mg/lpercentile 83
• PotassiumK5.66 mg/lpercentile 78
• SodiumNa16.2 mg/lpercentile 73
• ChloridesCl20.9 mg/lpercentile 70
• MagnesiumMg17.3 mg/lpercentile 57
• BicarbonatesHCO3224 mg/lpercentile 54
• SulphatesSO439.6 mg/lpercentile 49
• CalciumCa59.3 mg/lpercentile 45

dot: average along the water line, line: from the lowest to the highest value, scale: position among sample points on streams in Slovakia (0 to 100th percentile)

Nutrients and organic pollution

• Chemical oxygen demandChSK6.63 mg/lpercentile 91
• PhosphatesPO40.590 mg/lpercentile 85
• AmmoniumNH40.154 mg/lpercentile 61
• NitratesNO35.81 mg/lpercentile 46

Metals

• IronFe0.720 mg/lpercentile 95
• ManganeseMn387 μg/lpercentile 95
• AluminiumAl537 μg/lpercentile 95
• ZincZn9.03 μg/lpercentile 61

Elements in river sediments

The Geochemical Atlas of Slovakia (river sediments) describes what the river carries in the fine material on its bed. Sediment collects metals from rocks, ore occurrences and past mining and industry. It is not a legal limit or a health risk assessment: it shows how an element on this stream ranks among streams in Slovakia.

Potentially toxic and trace elements

• ZincZn164 mg/kgpercentile 84
• MercuryHg0.212 mg/kgpercentile 76
• BismuthBi0.301 mg/kgpercentile 73
• VanadiumV79.2 mg/kgpercentile 71
• SeleniumSe0.326 mg/kgpercentile 67
• ChromiumCr83.4 mg/kgpercentile 66
• TinSn3.09 mg/kgpercentile 65
• AntimonySb0.798 mg/kgpercentile 62
• LeadPb17.8 mg/kgpercentile 61
• NickelNi25.9 mg/kgpercentile 56
• MolybdenumMo0.402 mg/kgpercentile 55
• CadmiumCd0.194 mg/kgpercentile 52
• CopperCu23.5 mg/kgpercentile 50
• CobaltCo8.10 mg/kgpercentile 44
• ArsenicAs4.98 mg/kgpercentile 25

dot: average along the water line, line: from the lowest to the highest value, scale: position among sample points on streams in Slovakia (0 to 100th percentile)

Natural radioactivity and radon

Airborne gamma-ray spectrometry by ŠGÚDŠ measures radiation from potassium, uranium and thorium in rocks and soil. Granites and some acidic volcanic rocks have the highest values, limestones and floodplains the lowest. Caesium-137 is a remnant of fallout from the Chernobyl accident and nuclear weapons tests.

• Equivalent thorium (eTh)eTh7.82 ppm64th percentile
• Potassium (K)K1.31 %percentile 55
• Equivalent uranium (eU)eU2.48 ppm38th percentile

dot: average along the water line, line: from the lowest to the highest value, scale: position among sample points on streams in Slovakia (0 to 100th percentile)

• Areal activity of 137CsCS137506 Bq/m²percentile 4

Radon risk by isopleths

• low100%SR 36 %

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Geophysical fields: magnetics and gravity

Maps of the magnetic field and gravity (ŠGÚDŠ) reveal what lies beneath the sediments and the surface: volcanic bodies, faults and crustal thickness. For an angler they are interesting indirectly: they show where the bedrock changes, and with it the water.

Geothermal potential

The Atlas of Geothermal Energy of Slovakia records rock temperature and heat flow from the Earth's interior. It is the potential of the area, not the actual warmth of the water in the stream. Specific geothermal boreholes and springs near this water are in the geothermal energy section below.

Geothermal groundwater bodies beneath the water line

• Trebišov Basin50%SR 0.9 %
• Humenné Ridge50%SR 4.4 %

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Relief, climate and soils

A basin is not just water: slope and elevation determine the speed of runoff, climate the temperature and amount of water, and soils what is washed into the stream. The data come from the geomorphological division, climatic-geographical types and soil maps of ŠGÚDŠ.

• Elevation of geomorphological units (from–to)97–183m a.s.l.
• Average elevation of the units105m a.s.l.
• Average slope0.4°
• Average January temperature-2.7°C
• Average July temperature19.1°C
• Annual precipitation666mm

Geomorphological units

• East Slovak Plain100%SR 3.8 %

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Geomorphological regions

• East Slovak Lowland100%SR 4.9 %

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Climatic-geographical types

• lowland climate100%SR 38 %

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Susceptibility of soils to acidification

• soils susceptible to acidification50%SR 31 %
• soils moderately susceptible to acidification50%SR 25 %

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Soil contamination (map 1:500,000)

• relatively clean soil56%SR 53 %
• uncontaminated soil, the geogenically determined content of some risk elements reaches limit values A44%SR 45 %

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Lithogeochemical types

• Neogene100%SR 48 %

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Map of the corridor

Where the nearest mine workings, deposits, burdens, geothermal boreholes and gold finds are. Groups can be switched off.

Trace elements in surface waters

Arsenic, antimony, cadmium, lead, copper, zinc and other elements in samples from rivers and streams (Geochemical Atlas of Slovakia, surface waters, 2015). The bar shows where the highest value lies among all samples in Slovakia; the light marker is the median of the samples at this water.

• ChromiumCrextreme (top 1 %)
  highest 17.2 μg/lmedian 1.83 μg/l14 samples14 % below the limit of quantification
  1. up to 50 %
  2. 50–75
  3. 75–90
  4. 90–99
  5. above 99

  Highest value: Čierna voda, kanál2000, 80 m from the water. Comparison: percentile 99 of all samples in Slovakia.

• CopperCuelevated (top 10 %)
  highest 7.80 μg/lmedian 1.70 μg/l14 samples29 % below the limit of quantification
  1. up to 50 %
  2. 50–75
  3. 75–90
  4. 90–99
  5. above 99

  Highest value: Stretávka, 900 m SV od K1041999, 570 m from the water. Comparison: percentile 95 of all samples in Slovakia.

• SeleniumSeelevated (top 10 %)
  highest 0.530 μg/lmedian 0.500 μg/l14 samples93 % below the limit of quantification
  1. up to 50 %
  2. 50–75
  3. 75–90
  4. 90–99
  5. above 99

  Highest value: Čierna voda, kanál2000, 30 m from the water. Comparison: percentile 92 of all samples in Slovakia.

• ArsenicAselevated (top 10 %)
  highest 4.27 μg/lmedian 1.50 μg/l14 samples
  1. up to 50 %
  2. 50–75
  3. 75–90
  4. 90–99
  5. above 99

  Highest value: Iňačovce, kanál, 2500 m V od k 1042000, 820 m from the water. Comparison: percentile 91 of all samples in Slovakia.

• LeadPbelevated (top 10 %)
  highest 4.00 μg/lmedian 2.50 μg/l14 samples93 % below the limit of quantification
  1. up to 50 %
  2. 50–75
  3. 75–90
  4. 90–99
  5. above 99

  Highest value: Stretávka, 900 m SV od K1041999, 570 m from the water. Comparison: percentile 90 of all samples in Slovakia.

• StrontiumSrslightly elevated
  highest 450 μg/lmedian 299 μg/l14 samples
  1. up to 50 %
  2. 50–75
  3. 75–90
  4. 90–99
  5. above 99

  Highest value: Stretávka, 900 m SV od K1041999, 570 m from the water. Comparison: percentile 87 of all samples in Slovakia.

• AntimonySbslightly elevated
  highest 0.900 μg/lmedian 0.500 μg/l14 samples86 % below the limit of quantification
  1. up to 50 %
  2. 50–75
  3. 75–90
  4. 90–99
  5. above 99

  Highest value: Blatné Revištia, kanál pri polnej ceste1998, 380 m from the water. Comparison: percentile 81 of all samples in Slovakia.

• LithiumLibelow half of Slovakia
  highest 5.00 μg/lmedian 5.00 μg/l14 samples100 % below the limit of quantification
  1. up to 50 %
  2. 50–75
  3. 75–90
  4. 90–99
  5. above 99

  Highest value: Stretávka, Uh, 1700 m ZJZ od k 1002000, 470 m from the water. Comparison: percentile 34 of all samples in Slovakia.

• CadmiumCdbelow half of Slovakia
  highest 0.150 μg/lmedian 0.150 μg/l14 samples100 % below the limit of quantification
  1. up to 50 %
  2. 50–75
  3. 75–90
  4. 90–99
  5. above 99

  Highest value: Stretávka, Uh, 1700 m ZJZ od k 100, 470 m from the water. Comparison: percentile 26 of all samples in Slovakia.

Major ions, mineralisation and pH

Basic water chemistry: which rocks the minerals in it come from.

• Silicon dioxideSiO2slightly elevated
  highest 25.3 mg/lmedian 19.1 mg/l12 samples
  1. up to 50 %
  2. 50–75
  3. 75–90
  4. 90–99
  5. above 99

  Highest value: Čierna voda, kanál1998, 40 m from the water. Comparison: percentile 83 of all samples in Slovakia.

Gold and ore minerals in river sediments

Regional panning prospecting: the heavy fraction was washed out of river gravel and the mineral grains in it were counted. The map of finds is positive: a sample without gold is not listed in the atlas, so the absence of a find is not proof that there is no gold.

• Ilmenit (FeTiO₃)7 samples, at most 4115 grains
• Limonite (FeO(OH)·nH₂O)7 samples, at most 55 grains
• Magnetite (Fe₃O₄)7 samples, at most 55 grains
• Rutil (TiO₂)5 samples, at most 55 grains
• Anatas (TiO₂)3 samples, at most 5 grains
• Pyrite (FeS₂)2 samples, at most 5 grains
• Cinabarit (HgS)1 sample, at most 1 grains
• Kasiterit (SnO₂)1 sample, at most 1 grains

Rock-forming and accessory minerals

• Pyroxény ((Mg,Fe,Ca)₂Si₂O₆)7 samples, at most 4115 grains
• Zirconium (ZrSiO₄)7 samples, at most 55 grains
• Granáty ((Fe,Mg,Ca,Mn)₃Al₂Si₃O₁₂)5 samples, at most 55 grains
• Korund (Al₂O₃)5 samples, at most 5 grains
• Amfiboly (Ca₂(Mg,Fe)₅Si₈O₂₂(OH)₂)1 sample, at most 5 grains
• Spinel (Cr-spinel) ((Mg,Fe)(Al,Cr)₂O₄)1 sample, at most 5 grains
• Apatit (Ca₅(PO₄)₃(F,Cl,OH))1 sample, at most 15 grains
• Epidot (Ca₂(Al,Fe)₃Si₃O₁₂(OH))1 sample, at most 5 grains

Groundwater: chemistry, water types and radioactivity

Hydrogeochemical objects (analyses of springs and boreholes), the geochemical atlas of groundwater (1996) and radiohydrochemical sampling. Groundwater feeds streams, so its composition also affects the water in the stream.

Metals in groundwater

• ChromiumCrextreme (top 1 %)
  highest 23.6 μg/lmedian 0.250 μg/l53 samples58 % below the limit of quantification
  1. up to 50 %
  2. 50–75
  3. 75–90
  4. 90–99
  5. above 99

  Highest value: studňa1993, 1.8 km from the water. Comparison: percentile 99 of all samples in Slovakia.

• LeadPbextreme (top 1 %)
  highest 18.0 μg/lmedian 1.00 μg/l53 samples42 % below the limit of quantification
  1. up to 50 %
  2. 50–75
  3. 75–90
  4. 90–99
  5. above 99

  Highest value: studňa1993, 1.2 km from the water. Comparison: percentile 99 of all samples in Slovakia.

• ZincZnextreme (top 1 %)
  highest 13,225 μg/lmedian 248 μg/l53 samples
  1. up to 50 %
  2. 50–75
  3. 75–90
  4. 90–99
  5. above 99

  Highest value: studňa1993, 530 m from the water. Comparison: percentile 99 of all samples in Slovakia.

• AluminiumAlextreme (top 1 %)
  highest 0.660 mg/lmedian 0.00500 mg/l53 samples51 % below the limit of quantification
  1. up to 50 %
  2. 50–75
  3. 75–90
  4. 90–99
  5. above 99

  Highest value: studňa1993, 2.5 km from the water. Comparison: percentile 99 of all samples in Slovakia.

• ArsenicAshigh (top 5 %)
  highest 13.3 μg/lmedian 0.500 μg/l53 samples70 % below the limit of quantification
  1. up to 50 %
  2. 50–75
  3. 75–90
  4. 90–99
  5. above 99

  Highest value: studňa1993, 2.5 km from the water. Comparison: percentile 98 of all samples in Slovakia.

• SeleniumSehigh (top 5 %)
  highest 5.50 μg/lmedian 0.500 μg/l53 samples62 % below the limit of quantification
  1. up to 50 %
  2. 50–75
  3. 75–90
  4. 90–99
  5. above 99

  Highest value: studňa1993, 220 m from the water. Comparison: percentile 98 of all samples in Slovakia.

• CopperCuhigh (top 5 %)
  highest 10.8 μg/lmedian 2.00 μg/l53 samples
  1. up to 50 %
  2. 50–75
  3. 75–90
  4. 90–99
  5. above 99

  Highest value: studňa1993, 1.5 km from the water. Comparison: percentile 97 of all samples in Slovakia.

• LithiumLihigh (top 5 %)
  highest 79.0 μg/lmedian 5.00 μg/l53 samples25 % below the limit of quantification
  1. up to 50 %
  2. 50–75
  3. 75–90
  4. 90–99
  5. above 99

  Highest value: studňa1993, 2.0 km from the water. Comparison: percentile 96 of all samples in Slovakia.

• CadmiumCdhigh (top 5 %)
  highest 0.900 μg/lmedian 0.250 μg/l53 samples75 % below the limit of quantification
  1. up to 50 %
  2. 50–75
  3. 75–90
  4. 90–99
  5. above 99

  Highest value: studňa1993, 390 m from the water. Comparison: percentile 96 of all samples in Slovakia.

• AntimonySbhigh (top 5 %)
  highest 0.900 μg/lmedian 0.100 μg/l53 samples81 % below the limit of quantification
  1. up to 50 %
  2. 50–75
  3. 75–90
  4. 90–99
  5. above 99

  Highest value: studňa1993, 390 m from the water. Comparison: percentile 95 of all samples in Slovakia.

• IronFetypical value
  highest 0.00500 mg/lmedian 0.00500 mg/l37 samples100 % below the limit of quantification
  1. up to 50 %
  2. 50–75
  3. 75–90
  4. 90–99
  5. above 99

  Highest value: studňa1993, 2.0 km from the water. Comparison: percentile 50 of all samples in Slovakia.

• MercuryHgbelow half of Slovakia
  highest 0.100 μg/lmedian 0.100 μg/l53 samples100 % below the limit of quantification
  1. up to 50 %
  2. 50–75
  3. 75–90
  4. 90–99
  5. above 99

  Highest value: studňa1993, 2.0 km from the water. Comparison: percentile 46 of all samples in Slovakia.

Radon in waters

Mine workings, deposits and ore occurrences

Old mine workings outside mining areas (Geofond register), deposits and mining areas, and the metallogenetic map. Gold, silver and other metals near streams can get into sediments and water.

Deposits and mining areas

Boreholes and Geofond archive reports

Register of hydrogeological boreholes, other boreholes and geothermal boreholes. Each borehole has a report in the Geofond archive (geological profiles, pumping tests, chemical analyses of the water); the report number is in the table.

372 boreholes in the 3 km zone, of which 75 hydrogeological and 297 other; with an archive report number 280.

Borehole depths

• up to 10 m10×
• 10–30 m31×
• 30–100 m47×
• 100–300 m37×
• over 300 m244×

Nearest boreholes

Geothermal energy and mineral waters

Geothermal boreholes (wellhead water temperature, yield, chemical type) and sources of geothermal and mineral waters within 10 km. Data on the use and existence of a borehole come from the Geofond register.

Sources of geothermal and mineral waters

Environmental burdens, landfills and anthropogenic sediments

Recorded environmental burdens (industrial sites, landfills, mining), the register of waste landfills and monitoring of anthropogenic sediments (industrial sludge). It is a list of places, not a measurement of water pollution.

Waste landfills