Fishing district boundaries: Čiastkové povodie rieky Ondava od cestného mosta v obci Lomné po cestný most medzi obcami Duplín a Stročín a potoky Brusnička, Vojtovec a Chotčianka od ústia po pramene. The score, the best window of the day and what pushes it up or down Loading data… Water level, temperature, modelled flow and gradient Stropkov – Ondava · level stable The level is measured at an SHMÚ gauge; it is not the depth of the water in the fishing district. Loading data… Fast watercourse Podhorský potok: fast water, stony bottom, riffles and the pools below them. Typical trout waters. Hour by hour, pressure and the next few days Loading data… Where the sun and moon are right now and when the best windows of the day will come Drag along the axis to see where the sun and moon will be. The day lasts 9 h 26 min. Full moon around 24 Nov, new moon around 9 Nov. Solunar theory is not scientifically confirmed; we treat it as a supplement. The golden hour is the time around sunrise and sunset, when fish often bite. Course of the water, spots along the water, character and basic data The line shows the course of the fishing district according to the "Rybárske revíry" data 2026. Verify access points and exact boundaries on site. Fish have somewhere to retreat from both heat and cold. On still waters a temperature layer (thermocline) can form in summer. Well-oxygenated water and plentiful food (aquatic insect larvae). Typical of the grayling and barbel zones; gravel bars also serve many fish as spawning grounds. Shallower sections with fewer shelters. In lowland streams they alternate with muddy ones; fish keep to banks, roots and obstacles. Slow lowland waters and carp fishing districts. Mud hides food, but in summer there may be less oxygen near the bottom, and lures sink into it. Even depth and current. Fish stay near the bank, stones, roots and at the boundary of faster and slower current. In summer the water warms up quickly and aquatic plants and algae thrive here. At midday fish move to deeper places. Grows by the water; the roots stabilize the bank and create shelters beneath the surface. The branches hang over the water and provide shade and insects. A typical tree of stream and river banks. A dense root system creates undercut banks and shelters, and the leaves decompose quickly. Fish can move freely along the watercourse; the section is more continuous. The explanation is general and based on the fishing district description in the data and on common fishing practice. Actual conditions on site may differ; check them before you fish. Spots within 3 km of the watercourse are shown. Closed season, fishing hours, minimum sizes and daily limit. For guidance only: check them in the fishing regulations of the fishing district 15 Mar – 31 May fishing for all fish prohibitedoutside this period The ban does not apply 1 May – 31 May during fishing competitions (§ 13, para. 3). It also does not apply to carp waters that are watercourses (but not reservoirs, dead-end, dead and cut-off arms), or to other water bodies (§ 13, para. 5). Check in the fishing regulations of the district which case your district is. The protection periods by species (below) apply independently of this closed season. Applies only outside the closed season. Outside these hours fishing is prohibited (§ 14(b) of the Act). January to April, November, December6.00 – 21.00 h May4.00 – 24.00 h June to October0.00 – 24.00 h Months missing from the table fall within the closed season. The hours in November and December on trout and grayling waters relate to the exception for fishing huchen (§ 13, para. 4 of the Act); check in the fishing regulations what may be caught at that time. On border waters the hours in the permit or the fishing regulations apply (§ 11, para. 2 of the Decree). The Act regulates night fishing in two wordings that seem to contradict each other at first sight, so always ask about it in the fishing regulations of the district or the fishing guard. This is a summary. For baits, hooks and groundbait also read the fishing regulations of the district, because the user may tighten the conditions. The blue and green groups cannot be combined. The limit applies per day, also when fishing in several districts, and once it is reached, fishing for that day ends. The species groups follow the SRZ interpretation of January 2026, not the text of the section directly. The district user may set a lower limit in the permit, in which case the stricter one applies. During this period the species must not be caught, even if the water type otherwise allows fishing at that time. It applies independently of the closed season for all fish. Some species are protected all year round (for example zingel and streber, lampreys, gudgeons, spined loaches, maraena whitefish, Carpathian barbel, sabre carp) and fishing for them is always prohibited. The full list of species is in the guide The fishing law, rule by rule. The shortest length from which you may keep a fish. The district user may raise the size, so look for the valid value in the permit and the fishing regulations. Total length is measured from the front of the head to the end of the longest ray of the tail fin (§ 12, para. 4). No minimum size applies, for example, to sunbleak, Prussian carp, European perch, roach, stone loach and invasive species. As of 6 Nov 2026: Act no. 216/2018 Coll. on fisheries (wording effective 1 Jan 2022) and Decree no. 381/2018 Coll. (wording effective 1 Jan 2019); we found no newer wording. The law may change; you can find the current wording on Slov-Lex (Act) and Slov-Lex (Decree). On the same stream and nearest in the basin Loading the 3D terrain model… Water quality, river basin, bottom, fish, aquatic insects, wildlife and hazards from open databases. Except for wildlife and hazards, they are also included in the activity score. The water is in the bottom 6% of 897 carp fishing districts with data. Reliability medium: we used 5 water data points; the rest are missing and are not part of the assessment. gradient 13 ‰, 331 m a.s.l. → grayling zone Based on gradient and elevation, the stream lies in an area that corresponds to the grayling zone. This is not a natural zone for carp and cyprinids; the fish are here more thanks to stocking and local conditions. European streams are divided from source to mouth into zones with typical fish: trout, grayling, barbel and lowland; they are determined mainly by gradient and stream size (Huet 1959), and the zones can also be used to assess the condition of streams (Aarts and Nienhuis 2003). We estimate the zone from the gradient of the fishing district's line and its elevation; it is a simplification without stream width. A match between the zone and the fishing district type adds +1 to quality, a clear mismatch −1. Sources: Huet 1959; Aarts and Nienhuis 2003 ≈ 15.0 °dH (2.7 mmol/l of calcium and magnesium), ŠGÚDŠ atlas Harder water with enough calcium and magnesium is more productive, has a larger food supply and buffers acidity swings better. Water with calcium and magnesium is more productive and buffers acidity swings better: trout production was higher in calcareous hard waters (Almodóvar et al. 2006), and an index based on dissolved solids and depth predicts fish yield from lakes (Ryder et al. 1974). In Irish streams, however, geology did not change trout density (Lehane et al. 2004), and Downing et al. (1990) showed that production is related rather to primary production. Hence only ±1 point. Hardness comes from the ŠGÚDŠ atlas, not from a measurement in the fishing district; it replaces the separately assessed bedrock of the basin. Sources: Almodóvar et al. 2006; Lehane et al. 2004; Ryder et al. 1974 pH 8.2, ŠGÚDŠ atlas The pH is within the range in which fish commonly thrive. Below about pH 6 fish suffer, and trout and grayling are more sensitive than cyprinids (Alabaster and Lloyd 1982); in acidic soft water, aluminium is released from the soil and damages gills (Gensemer and Playle 1999). The pH from the atlas is a model estimate, so the reduction is only −1 or −2, and only where we have no pH measurement (which is assessed by a separate factor). Sources: Alabaster and Lloyd 1982; Gensemer and Playle 1999 ≈ 439 mg/l, ŠGÚDŠ atlas Medium mineralisation corresponds to productive streams and reservoirs. Dissolved solids (mineralisation) are related to the fertility of the water, which is why Ryder used them to estimate fish production in lakes (Ryder 1965, Ryder et al. 1974). Downing et al. (1990) showed, however, that primary production is a better predictor of production. It does not enter the score, only the suitability index. Sources: Ryder 1965; Ryder et al. 1974; Downing et al. 1990 1 elements among the highest 10 % in Slovakia (ŠGÚDŠ atlas 1999) Metals in sediment can accumulate in benthic animals and fish; high values are often natural in ore areas. In hard water metals are less toxic, because calcium competes for sites on the gills. The toxicity of metals to fish decreases with water hardness, because calcium competes with the metal for sites on the gills (Pagenkopf 1983). The ŠGÚDŠ atlas gives only the rank among streams, not a concentration comparable with a limit (MacDonald et al. 2000). In hard water we therefore rate metals more leniently, in soft water more strictly. Sources: Pagenkopf 1983; Gensemer and Playle 1999; MacDonald et al. 2000 The same water data evaluated against the requirements of trout, grayling and carp. The fishing district is registered as a carp district; its type is highlighted. The index 0 to 100 compares the properties of the water with the requirements of the species (60 is the neutral value, 100 the ideal). The verbal rating comes from comparison with other fishing districts of the same type, because most Slovak waters have good values for their species. The index does not affect whether fish really occur in the fishing district (that is decided by stocking and the manager). Hardness, pH and mineralisation from the atlases are historical and model estimates. Only a small part of this feeds into the conditions score and fishing district quality (hardness ±1, atlas acidity −2 to 0, stream zone match ±1 to quality). We assessed 17 factors; 5 of them change the score. The adjustments range from −14 to +12 points so that they do not outweigh the weather and water temperature. They are counted in the score, in the ranking and in the filters. ≈ 15.0 °dH, ŠGÚDŠ atlas Harder water is more productive, has more food and buffers acidity swings better. Water with calcium and magnesium is more productive and buffers acidity swings better: trout production was higher in calcareous hard waters (Almodóvar et al. 2006), and an index based on dissolved solids and depth predicts fish yield from lakes (Ryder et al. 1974). In Irish streams, however, geology did not change trout density (Lehane et al. 2004), and Downing et al. (1990) showed that production is related rather to primary production. Hence only ±1 point. Hardness comes from the ŠGÚDŠ atlas, not from a measurement in the fishing district; it replaces the separately assessed bedrock of the basin. Sources: Almodóvar et al. 2006; Lehane et al. 2004; Ryder et al. 1974 site Svidník, above on Ondava, 9.7 km from the fishing district, standard not met in 3 of 4 years (2022 to 2025) The nearest SHMÚ monitoring site on this watercourse does not meet water quality standards. Lack of oxygen and organic pollution weaken fish directly, ammonium ions and nitrites are toxic to them, and further nutrients promote algae. All four years are counted, and newer ones carry more weight. An unmet standard does not mean the fish do not bite; the reduction is at most 5 points. The nearest SHMÚ monitoring site on the same watercourse: unmet water quality standards for the years 2022 to 2025 (newer years carry more weight). Lack of oxygen and organic pollution directly weaken fish (Davis 1975), ammonium and nitrites are toxic, and nutrients feed algae. The exact amount by which an unmet standard lowers the bite is not verified, so this is angling practice and caution. The deterioration is at most 5 points and only lowers: what SHMÚ does not report is not proof of cleanliness. Benzo(a)pyrene and other PAHs are not counted in the score because most watercourses exceed their extremely low standard. Sources: SHMÚ, surface waters; Government Regulation of the SR no. 269/2010; Davis 1975 nitrates typically 1.6 mg/l (standard 50), ammonium above the standard at 1 of 7 stations Groundwater reaches streams as base flow and carries nitrogen from fields and waste. Nitrates feed algae and contribute to nighttime oxygen crashes; nitrites are toxic to fish. Nitrites and ammonium can also be natural in deep groundwater, so at most one point is deducted for them. The data reliability is 100% (7 stations within 10 km, nearest 0.1 km, data from 2025), and the adjustment was applied in full. Groundwater reaches streams as base flow. The typical nitrate value from stations within 10 km (moderate from 25 mg/l, significant from 50 mg/l, which is the drinking-water standard) indicates how much nitrogen the water brings: it feeds algae and contributes to night-time oxygen crashes (Camargo et al. 2005). Nitrites and ammonium above the standard at any station add one point, because nitrites are poisonous to fish (Lewis and Morris 1986); in deep groundwater they can also be natural, so only one point. The adjustment is multiplied by the reliability of the data. Sources: SHMÚ, groundwater; Camargo et al. 2005; Lewis and Morris 1986 metals and metalloids (above the standard at 1 of 7 stations), highest value 1.7 times the standard Metals, pesticides, PFAS and chlorinated solvents above the standard show the burden on the surroundings. The standards are set for drinking water and are stricter than the limits harmful to fish, so the reduction is small; metals can also come from rocks. PAHs are not counted in the score. Data reliability is 100% (7 stations within 10 km, the nearest 0.1 km, data from 2025); the adjustment was applied in full. Metals and metalloids, pesticides, PFAS and chlorinated solvents above the standard at stations within 10 km. The standards are drinking-water standards and stricter than the limits harmful to fish, so the reduction is small: one point for one or two groups of substances, two points for three groups or for a value at least five times above the standard. Metals are poisonous to fish, more so in soft water (Pagenkopf 1983), and PFAS accumulate in tissues (Giesy and Kannan 2001); metals can also come from rocks. PAHs are not counted. The adjustment is multiplied by the reliability of the data. Sources: SHMÚ, groundwater; Pagenkopf 1983; Giesy and Kannan 2001 0.0× the average month, 0 of 15 observations in the year, iNaturalist Aquatic insects are scarce this month; food near the bottom matters more. Anglers fish "by the insects" (dry and wet fly). A measured relationship between catches and insect hatches is not documented in our sources. Data for these factors is missing or within the normal range: The rules are indicative and based on fishing practice and scientific studies; for each factor you can see how well it is supported. Weather, air pressure and water temperature affect the score more than this data does. The data comes from the SHMÚ yearbooks (surface waters 2022 to 2025). The yearbook lists the sites that failed the standard; a site missing from the yearbook is not considered clean. We determine the distance and the match of the watercourse name ourselves, so the assignment is indicative. Exceeded in 2025: Exceeded in 2025: Last exceeded in 2020: Exceeded in 2025: Exceeded in 2025: Exceeded in 2025: Exceeded in 2025: Groundwater reaches streams as base flow, so the connection to the stream at the fishing district is only indirect. Natural substances (iron, manganese, sulfates, conductivity) are not counted in the yearbook-based assessment. The data comes from the SHMÚ yearbooks (groundwater 2017 to 2025). Treatment plants within 2 km of the fishing district. The treatment plant need not lie upstream of the fishing district; we do not assess the watercourse at the plant. Load is the ratio of the pollution produced to the capacity of the treatment plant (PE = population equivalent). Watercourse from the HydroRIVERS database matched with the fishing district, line deviation about 254 m The data come from a global database with a coarser resolution (tens of metres), so they are only approximate for small waters. Depth and volume are model averages. Rocky sills and stones provide hiding places, but rigs tend to snag here. According to the geological map: fluviálne sedimenty: resedimentované nivné piesčité štrky prikorytovej zóny, holocén | fluviálne sedimenty: litofaciálne nečlenené nivné hliny, alebo piesčité až štrkovité hliny dolinných nív a nív horských potokov, holo The fishing district description states the bottom: gravel, sand, fine-grained, muddy; the geological map shows something different, and the district description is more precise. The map shows the bedrock geology, not the exact bottom at the spot. The actual bottom material may differ, especially where sediment has been deposited. Few insects November: 0.0× the average month 0.0× the average month, 0 of 15 observations in the year, iNaturalist. The observations are added by people from the surrounding area; they are not measurements at the water. They show when aquatic insects usually appear and are useful mainly for fly fishing. A typical value from 7 groundwater stations within 10 km of the fishing district (nearest 0.1 km), measured in 2025. Closer stations carry more weight. This is groundwater near the district, not a measurement in the watercourse itself. The standard is the limit that SHMÚ gives for the indicator (for drinking water); a value equal to the standard counts as an exceedance, as it does at SHMÚ. The label "somewhere above the standard" means that the typical value is below the standard but at least one station exceeds it; which one is shown on the tile. Fish are more sensitive to some substances than people are. 0.005mg/l above the standard somewhere Standard 0.5 mg/l. Range 0.005 to 0.5 mg/l, 7 stations. Above the standard: 1 of 7 (Minovce, 0.5 km from the fishing district). 0.01mg/l far below the standard Standard 0.5 mg/l. Range 0.01 to 0.03 mg/l, 7 stations. 1.6mg/l far below the standard Standard 50 mg/l. Range 0.5 to 7.5 mg/l, 7 stations. 1.23mg/l low oxygen Mark on the dial: 9 mg/l, the guideline for salmonid waters. Range 0.47 to 8.97 mg/l, 7 stations. 11.2°C warmer Range 9.5 to 11.6 °C, 7 stations. 7.04 suitable for fish Range 6.81 to 7.23, 7 stations. 2.91mmol/l moderately hard Range 2.37 to 4.52 mmol/l, 7 stations. 0.086mg/l above the standard somewhere Standard 0.2 mg/l. Range 0.002 to 2.78 mg/l, 7 stations. Above the standard: 4 of 7 (highest: Vysne Cabiny – Krasny Brod, 8.1 km from the fishing district). 0.086mg/l above the standard Standard 0.05 mg/l. Range 0.001 to 2.49 mg/l, 7 stations. Above the standard: 5 of 7 (highest: Strocin, 2.3 km from the fishing district). 16.8mg/l far below the standard Standard 250 mg/l. Range 1.3 to 209 mg/l, 7 stations. 60.5mg/l below the standard Standard 250 mg/l. Range 21.7 to 84.7 mg/l, 7 stations. 58.3mS/m below the standard Standard 125 mS/m. Range 43.2 to 112 mS/m, 7 stations. 70% of standard close to the standard Highest: Aluminium 0.33 mg/l (165% of the standard, 2.3 km from the fishing district). 7 stations. Above the standard: 1 of 7. 0% of standard not detected Below the limit of quantification: substances from this group were not detected in the samples. 1 station. 0% of standard not detected Below the limit of quantification: substances from this group were not detected in the samples. 3 stations. 0% of standard above the standard somewhere Highest: benzo(a)pyrene 0.01 µg/l (100% of the standard, 0.1 km from the fishing district). 3 stations. Above the standard: 1 of 3. Sources Species that have been observed or recorded around the water. Wildlife, plants and hazards do not enter the fishing conditions score and are for information only. The name of a species leads to its page. An insect with aquatic larvae. Adults live only briefly and hatch all at once in swarms. Predatory insect. The larvae live underwater for several months to years; adult dragonflies hunt in the air above the water. The most common duck; it nests by almost every water with bankside vegetation. It stands in the shallows and lies in wait for small fish. It is easy to see along the banks of ponds and slow streams. A small bird that dives for little fish. It nests in steep banks of clean streams. A small bird that dives and runs along the bed of rapids after insect larvae. Nests by clean mountain streams. Black with yellow spots. Lives in deciduous forests by clean mountain streams; the larvae develop in the stream. A shy forest bird that nests in old forests and goes to streams and wetlands to hunt fish and frogs. The largest native toad. In spring it migrates to water, where it breeds. A herbivore that changes the stream and its banks with dams and burrows. It is protected. It creates shallows and pools where fish and insects thrive. A harmless snake with two yellow spots on the nape. It swims well and hunts frogs, fish and newts. It hunts fish, crayfish and frogs. It is strictly protected, and its presence is considered a sign of fairly clean water with plenty of fish. An invasive herb from East Asia that forms dense stands up to three metres tall. An invasive plant from the Himalayas, up to two metres tall, with pink flowers. It overgrows the banks of watercourses. A riparian tree whose roots reach below the water surface. A wetland plant with a brown cylindrical fruiting spike. Tall grass that forms extensive reed beds around ponds and on banks. A tiny floating plant that can cover the whole surface of standing water. Lives in the mountain forests of northern and central Slovakia. Near water it hunts fish and drinks. How to protect yourself: In mountain districts move noisily, do not leave fish, entrails or bait leftovers near your tent, and store food away from where you sleep. If you see a bear, do not run, talk calmly and back away slowly. Never approach the cubs. They breed in standing water, so they are worst around reservoirs, oxbow lakes and floodplain forests, especially at sunset. How to protect yourself: When fishing in the evening and at night wear long sleeves, repellent and a net. Warmth and humidity after rain speed up mosquito development. A venomous snake that basks on rocky slopes, in wetlands and at forest edges near water. How to protect yourself: It is shy and bites only when threatened. On rocky banks do not reach with your hand between the stones, and wear sturdy footwear. After a bite stay calm, do not move the affected limb and call 112. A shy predator of the forests. It comes to the water at night and at dusk. How to protect yourself: Attacks on people are very rare. Keep your camp tidy, do not feed wildlife and keep your dog on a leash. It comes to the water to wallow and drink, mainly at dusk and at night. How to protect yourself: A wild boar sow with piglets can be aggressive. Keep your distance, do not spend the night on a game trail and do not leave food scraps near the water. An invasive plant that grows along stream banks and on wet meadows. In sunlight its sap causes skin burns. How to protect yourself: Do not touch it and do not walk through the vegetation. If the sap gets on your skin, wash it off with water and soap and protect the area from the sun. See a doctor for larger burns. Large biting flies. They are most active on hot, windless days near water and on meadows. How to protect yourself: They sting painfully, especially in summer around midday. Light-colored clothing with long sleeves and repellent help. Wildlife, plants and hazards: records come from observations and also reflect where observers move around; they are not density measurements or a guarantee of an encounter. They apply to the surroundings of about 35 × 55 km. Bedrock, watercourse and springs on the map, values at the location of the water, geomagnetic activity and earthquakes. This is information about the environment; only small hypotheses marked with a confidence level (faults and rocks, geomagnetic storm) enter the score. The bedrock map needs JavaScript to be turned on. Geological map of Slovakia 1 : 50,000: rocks beneath the surface, from alluvial gravels and sands through clays to granites and limestones. Colors follow the ŠGÚDŠ legend; clicking the map shows a description of the rock at that spot. For anglers: Gravel bars and rocky riffles give a clean bottom and habitat for zander, perch and barbel. Clayey and muddy ground holds food for carp and bream. Limestone and dolomite give harder water that is richer in food than granite and quartzite. Radon risk of the bedrock (low, medium, high). It is based on the radioactivity of rocks and on fissures. The map shows the bedrock, not radon in water. For anglers: Radon is a natural tracer of groundwater. Bedrock with a higher radon risk (granite, gneiss, tectonic faults) tends to be where fissure water comes to the surface. Most of Slovakia is "medium", so mainly a high risk is of interest. Equivalent uranium in surface rocks from airborne gamma spectrometry (ppm). From 4 ppm the bedrock is usually classified as having an elevated radon risk. For anglers: A high uranium level is a sign of granite, gneiss and black shales, that is, rocks from which radon and dissolved substances get into the water. It has no direct meaning for bites, but it helps to read the geology of the area. Gamma radiation dose rate in air (nGy/h) from an airborne survey. It is the natural background of the bedrock, not pollution. For anglers: Higher values are found in rocks rich in uranium, thorium and potassium (granite, gneiss, flysch with shales). It complements the uranium map; for an angler it mainly shows where the bedrock changes. Anomalies of the Earth's magnetic field (ΔT, in nT) caused by rocks with magnetic minerals, such as volcanic rocks, basalts or amphibolites. For anglers: Fish (especially salmonids and eels) sense the magnetic field. Whether local anomalies affect their movement and bites has not been shown; it is treated as a hypothesis. Click or tap the map to find the value at that location. low Bedrock with a low radon share. 2.5ppm common Typical background of the rocks. 7.0ppm below the crustal average Natural background of the rocks. 1.20% below the crustal average Natural background of the rocks. 47nGy/h around the world average Natural background of the bedrock. -26nT below the average of the surroundings Deviation of the magnetic field from the average of the surroundings. The values apply to a single spot (marked with a dot on the map), not as an average of the whole watercourse or river basin. Radon is a natural tracer in groundwater; the map does not include radon in water, only the bedrock risk. Mark on the dial: the average of the upper continental crust (uranium 2.7 ppm, thorium 10.5 ppm, potassium 2.3%; Rudnick and Gao 2003) and the world average of the natural outdoor dose 59 nGy/h (UNSCEAR 2000). The needle does not swing towards “good” or “bad”; it only shows where the value lies. Elevated uranium or radon is only information about the rock. It has no proven significance for bites; it helps to read what bedrock the water comes from. up to 1 km fault nearby Tectonic fault on the geological map. 0 none marked None within 1 km. expected reverse fault or thrust Fissure groundwater flows out of the bedrock along faults and at springs. It tends to be cooler in summer and warmer in winter than the water in the stream, so according to anglers' experience fish stay near such places in extreme weather (summer and winter islands of a more suitable temperature). However, fresh fissure water can have little oxygen. This is anglers' experience, not a phenomenon measured at this fishing district. Faults are from the geological map at 1 : 50,000. Springs come from a hydrogeological map that covers only some regions, so zero does not mean there are no springs there. The line is the water of the fishing district, the light band is the 3 km zone in which boreholes, mine workings and burdens were searched for. The map shows the nearest objects (at most a few dozen from each register), not all of them. The points correspond to the position in the register; area objects are marked by their centre. River alluvium78% of the water line 9% flysch, 9% young sediments Gravelly and sandy bottom and floodplains; the water is replenished from groundwater in the alluvium. Geological Map of Slovakia 1:50,000. pH 8.2modelled estimate water type Ca–HCO₃ Mineralisation 439 mg/l, hard water (15.0 °dH). Interpolation of measurements from the Geochemical Atlas of Slovakia, not a measurement in the stream. 1 from 15elements in the top 10 % highest: Nickel 41.3 mg/kg Position of the highest-ranked element among the sample points on streams in Slovakia: percentile 90. Interpolation of the Geochemical Atlas of river sediments. 45°C at 1,000 m depth heat flow 75 mW/m² At a depth of 2,000 m about 75 °C (increase of 30 °C per kilometre). Atlas of Geothermal Energy of Slovakia. 10samples with gold 16 ore minerals in the sediment Up to 2 grains in one sample (50 m from the water). Panning prospecting counted gold grains in a concentrate from river sediment. 2 from 9indicators in the top 5 % highest: Lead 13.0 μg/l Position of the highest measured value in the distribution of all surface water samples in Slovakia: percentile 99 (Ondava). 822boreholes within 3 km 1446 water analyses nearby Of these, 822 have an archive report from Geofond. The boreholes are hydrogeological, geological, engineering-geological and other. – 31 geothermal and mineral water springs within 10 km. 69sites within 3 km 5 environmental burdens, 64 landfills Nearest burden: Stropkov – obaľovačka, 170 m from the water. Proximity does not mean that substances leak from the site into the water. 15records within 5 km 3 deposits, 12 ore occurrences Geofond registers, the metallogenetic map and the mineral resources map. 253areas within 3 km 39 active Documented landslides in the Geofond register. A landslide into a stream can cloud the water and change the bed. The data come from registers, maps and atlases of the State Geological Institute of Dionýz Štúr and describe the environment around the water. Proximity of a mine working or burden does not mean the water is polluted. The chemistry of water and sediments is a modelled estimate from interpolated maps of the Geochemical Atlas of Slovakia, not current monitoring or a measurement in the stream. Detailed geology and geochemistry of the whole stream: rock under the water, water composition, elements in sediments, radiation, geothermal potential, metals, gold in sediment, mine workings, boreholes with analyses. Highest forecast Kp in the next 24 hours: 4.7 (unsettled field). Kp (0 to 9) measures the fluctuation of the Earth's magnetic field caused by the solar wind. From 5 it counts as a geomagnetic storm. Fish, especially salmonids and eels, sense the magnetic field. That their bites depend on Kp has not been shown, though: these are anglers' observations and hypotheses. The value is the same for the whole of Slovakia. It enters the activity score only during a strong geomagnetic storm (a hypothesis, −1 to −2 points). According to angling lore, fish (especially catfish and eels) react restlessly to tremors beforehand or stop biting. This is not reliably proven, and with weak tremors it is coincidence. People mostly do not notice deeper tremors from the Carpathians (for example near Komárno and Dobrá Voda) at all. The GEOFON catalog is global; weak tremors near Slovakia may not all be in it. It is not counted in the activity score. Data: © ŠGÚDŠ (geological, geophysical and hydrogeological maps), NOAA SWPC (Kp index), GFZ GEOFON (earthquakes). A link between the geomagnetic field, tremors or radon and fish bites has not been reliably proven, so they are not counted in the activity score. The method is described in Methodology. Sentinel-2 (optical) and Sentinel-1 (radar), updated roughly every 6 days Satellite data for this fishing district is being prepared. It is usually ready within a few minutes; refresh the page later. Changes in the surroundings and nature from 2019 to 2025: how the banks, vegetation and landscape around the water change. The images switch automatically; you can also browse them by hand. Orthophoto mosaic of Slovakia © GKÚ Bratislava, NLC Zvolen. The year and day of imaging depend on the location, so individual years may differ in season and weather.
By the water now
Fishing conditionsFish activity indexOur calculation (0–100): the base is set by water temperature, adjusted by light, turbidity, oxygen, weather and other factors according to how well they are supported by studies. For each factor you can see the confidence and the source. A planning aid, not a bite forecast.
Fishing conditions
Fish activity indexOur calculation (0–100): the base is set by water temperature, adjusted by light, turbidity, oxygen, weather and other factors according to how well they are supported by studies. For each factor you can see the confidence and the source. A planning aid, not a bite forecast.Water
Water level
Water levelThe water level at the nearest SHMÚ gauge in centimetres above the gauge zero. It is the water level at the station, not the depth of the water at the fishing district.Modelled flow
Modeled flowAn estimate of the amount of water in the river (m³/s) from the GloFAS model, not a measurement. The resolution is about 5 km, so on small streams it may show a larger river nearby.Elevation profile of the watercourse
Elevation profileHow the altitude of the watercourse changes downstream. It is calculated from a digital relief model (tens of metres), not from a water-level measurement, so it is approximate, especially for narrow streams.Weather and forecast
Weather and forecast
Sky: sun, moon and solunar windowsSolunar periodsCalculated from the position of the Moon: major periods (about 2 h) around the Moon's passage above and below the horizon, minor periods (about 1 h) around moonrise and moonset. A scientifically unconfirmed theory: in a study of 361 fishing trips (Quigley et al. 2023) it did not predict bites. We treat it as a hypothesis with a weight of at most ±2 points.
Sky: sun and moon
Solunar periodsCalculated from the position of the Moon: major periods (about 2 h) around the Moon's passage above and below the horizon, minor periods (about 1 h) around moonrise and moonset. A scientifically unconfirmed theory: in a study of 361 fishing trips (Quigley et al. 2023) it did not predict bites. We treat it as a hypothesis with a weight of at most ±2 points.Sun
MoonMoon phaseAt full and new moon the gravitational effect is strongest. On a clear full-moon night predators and carp often feed at night, and the day after may be weaker.
Windows of the daySolunar periodsCalculated from the position of the Moon: major periods (about 2 h) around the Moon's passage above and below the horizon, minor periods (about 1 h) around moonrise and moonset. A scientifically unconfirmed theory: in a study of 361 fishing trips (Quigley et al. 2023) it did not predict bites. We treat it as a hypothesis with a weight of at most ±2 points.
Map and fishing district data
49.31412, 21.79617
OpenStreetMap
Fishing district details
Characteristics
What this means for anglersexplanation of the bottom, vegetation, watercourse line and other data of this fishing district
Confluences and risk spots
Details
Details
Law and fishing rules
Closed season for all fish
§ 13, paragraphs 3 and 5 of the ActDaily fishing hours
§ 11 of the DecreeRods, baits and fishing days
§ 18 of the ActHow many fish you may keep per day
§ 14 of the DecreeProtection periods by species§ 10 of the Decree
Minimum sizes§ 12 of the Decree
Before and after fishing
News from the organization and catches from the fishing district
Catches from the fishing district
Other fishing districts nearby
On the Ondava stream
4-1650-1-1CarpOndava č. 1
Trebišov, Košice Region
4-1660-1-1CarpOndava č. 2a
Vranov nad Topľou, Prešov Region
4-1661-1-4CarpOndava č.2 b
Vranov nad Topľou, Prešov Region
4-1670-5-1Salmonid (grayling)Ondava č. 3
Vranov nad Topľou, Prešov Region
4-1690-1-1CarpOndava č. 5
Svidník, Prešov Region
4-1700-4-1Salmonid (trout)Ondava č. 6
Svidník, Prešov RegionNearest in the basin
4-1160-4-1Salmonid (trout)Laborec č. 5
Medzilaborce, Prešov Region
4-1151-4-1Salmonid (trout)Sukovský potok
Medzilaborce, Prešov Region
4-3320-4-1Salmonid (trout)VN Danova
Prešov Region
4-1170-4-1Salmonid (trout)Ladomírka č. 1
Svidník, Prešov Region
4-4130-4-4Salmonid (trout)Vydraňka
Medzilaborce, Prešov Region
4-3840-1-1CarpVN Stropkov
Prešov RegionTerrain in 3D
Water according to public sources
Water suitability for the fishing district type
Water suitability for the district typeIndex 0 to 100: how well the properties of the water match the needs of trout, grayling or carp, depending on the district type. It is not a bite forecast or a statement about which fish live there.What we know about it
What we know about it
What we know about it
What we know about it
What we know about it
How this water would suit each type
What follows from this
Public sources in the conditions scoreData on oxygen, nutrients, reservoir depth, watercourse size, bottom, fish species and insect swarming slightly adjust the "Fishing conditions" score. Each adjustment is shown separately in the score breakdown.Water and oxygen+1
What we know about it
Pollution−3
What we know about it
What we know about it
What we know about it
Life by the water0
What we know about it
Do not change the score
Water pollution
Water pollution (SHMÚ)Water quality indicators that fail the standards at the nearest monitoring site on the same watercourse in the SHMÚ yearbooks for 2022 to 2025.Surface water: nearest monitoring site
Other sites on the same watercourse
Groundwater nearby
Groundwater nearby (SHMÚ)Measured groundwater values from stations within 10 km of the fishing district (nitrates, harmful substances, ammonium, iron, chlorides) and the SHMÚ yearbooks.Groundwater within 10 km (7 stations)
Measured values, year 2025, sampling 1 Oct 2025 (2 samplings, the highest value of the year for each substance)
Measured values, year 2025, sampling 25 Sep 2025 (2 samplings, the highest value of the year for each substance)
Measured values, year 2025, sampling 19 Mar 2025
Show 4 more
Measured values, year 2025, sampling 1 Oct 2025 (2 samplings, the highest value of the year for each substance)
Measured values, year 2025, sampling 25 Sep 2025 (2 samplings, the highest value of the year for each substance)
Measured values, year 2025, sampling 25 Sep 2025 (2 samplings, the highest value of the year for each substance)
Measured values, year 2025, sampling 18 Sep 2025 (2 samplings, the highest value of the year for each substance)
Wastewater treatment plants
Wastewater treatment plants near the fishing districtPlants within 2 km of the district: overload, compliance with EU requirements and discharged load (BOD₅, COD, nitrogen, phosphorus in tonnes per year).River basin and reservoir
Reservoir depth (HydroLAKES)Average depth, volume and water retention time in the reservoir from the HydroLAKES database (WWF). The depth is estimated by a model from the surrounding terrain, so it is approximate.Bottom and bedrock
Bottom and bedrock (ŠGÚDŠ)The bedrock under the water according to the hydrogeological map of Slovakia at 1 : 50,000 (ŠGÚDŠ). It tells whether the surroundings are gravelly, sandy, clayey, muddy or rocky.Aquatic insects
Aquatic insect swarming (iNaturalist)How many observations of mayflies, caddisflies and stoneflies people nearby recorded this month compared with the annual average. For fly anglers it hints at insect hatches.
Mayflies0Mayflies: dry fly on the surface, especially at dusk.
Caddisflies0Caddisflies: in the evening and at night by the bank; a nymph and a wet fly also work.
Stoneflies0Stoneflies: clean, cold streams, often already at the end of winter and in early spring.Photo credits
Groundwater: measured values
Groundwater nearby (SHMÚ)Measured groundwater values from stations within 10 km of the fishing district (nitrates, harmful substances, ammonium, iron, chlorides) and the SHMÚ yearbooks.Ammonium
Nitrites
Nitrates
Oxygen
Water temperature
pH
Water hardness
Iron
Manganese
Chlorides
Sulphates
Conductivity
Metals and metalloids
Pesticides
Solvents and benzene
PAHs (combustion, petroleum substances)
How it affects fish and the water
Fish, wildlife, plants and hazards around the waterWildlife and hazards by the water (GBIF)Game animals, birds, plants and hazards (bear, ticks, mosquitoes, giant hogweed) that people have recorded around the water. It is not part of the fishing conditions score and is for information only.
WildlifeMayflies
Most records: May.
About the species
WildlifeDragonflies
Most records: August.
About the species
BirdMallard
Most records: August.
About the species
BirdGrey heron
Most records: July.
About the species
BirdCommon kingfisher
Most records: July.
About the species
BirdWhite-throated dipper
Most records: September.
About the species
WildlifeFire salamander
Most records: May.
About the species
BirdBlack stork
Most records: May.
About the species
WildlifeCommon toad
Most records: April.
About the species
WildlifeEurasian beaver
Most records: July.
About the species
WildlifeGrass snake
Most records: October.
About the species
WildlifeEurasian otter
Most records: September.
About the species
Invasive plantJapanese knotweed
Most records: August.
About the species
Invasive plantHimalayan balsam
Most records: August.
About the species
PlantBlack alder
Most records: July.
About the species
PlantBroadleaf cattail
Most records: July.
About the species
PlantCommon reed
Most records: June.
About the species
PlantCommon duckweed
Most records: July.
About the species
RiskBrown bear
Most records: June.
How to protect yourself
RiskMosquitoes
Most records: September.
How to protect yourself
RiskCommon viper
Most records: October.
How to protect yourself
RiskGray wolf
Most records: February.
How to protect yourself
RiskWild boar
How to protect yourself
RiskGiant hogweed
Most records: May.
How to protect yourself
RiskHorseflies
Most records: June.
How to protect yourself
Photo credits
Ground under the water: geology, faults and radon
low 36.7%
medium 63.0%
high 0.3%
no data
0 – 1
1 – 2
2 – 3
3 – 4
4 – 5
5 – 7
7 – 35no data0 – 2020 – 40
40 – 6060 – 8080 – 100100 – 140
140 – 180
180 – 220
220 – 999
-1 217 – -1 000
-1 000 – -250
-250 – -200
-200 – -190
-190 – -180
-180 – -170
-170 – -160
-160 – -150
-150 – -140
-140 – -130
-130 – -120
-120 – -110
-110 – -100
-100 – -90
-90 – -80
-80 – -60
-60 – -40
-40 – -20
-20 – 0
0 – 10
10 – 20
20 – 30
30 – 40
40 – 50
50 – 70
70 – 100
100 – 150
150 – 200
200 – 250
250 – 300
300 – 400
400 – 500
500 – 600
600 – 700
700 – 800
800 – 900
900 – 1 000
1000 – 1 100
1100 – 1 130Values at the water spot
Values at the water spotBedrock radon risk, uranium, thorium, potassium, gamma radiation and magnetic anomaly at a single spot by the water (marked with a dot on the map).Radon risk of the bedrock
Uranium (eU)
Thorium (eTh)
Potassium (K)
Gamma radiation
Magnetic anomaly (ΔT)
Faults and springs
Faults and springsThe distance to the nearest tectonic fault on the geological map and the number of springs nearby. Fissure groundwater flows out along faults.Nearest fault
Springs and outflows
Geology nearby: rock, water, sediments, boreholes
Geology and geochemistry around the waterRock under the water, composition of water and sediments according to the atlases, radioactivity, geothermal potential, boreholes, old mine workings, deposits, burdens, landslides and gold in sediments, from ŠGÚDŠ maps and registers.Rock under the water
Water according to the atlas
Elements in river sediment
Heat underfoot
Gold in river sediment
Trace elements in the stream water
Boreholes and groundwater analyses
Geothermal energy
Environmental burdens and landfills
Deposits and ore occurrences
Landslides and slope deformations
Geomagnetic activity
Geomagnetic activity (Kp)The planetary Kp index (0 to 9) measures the fluctuation of the Earth's magnetic field. From 5 it counts as a geomagnetic storm. The last 48 hours and a forecast for 24 hours are shown.Earthquakes nearby
Earthquakes nearbyTremors recorded within 150 km of the water in the last 30 days (GFZ GEOFON catalog).From space: what the Copernicus satellites show
Historical images
Nov0% illuminated
Depth: Deeper, 3–6 m
Bottom: Gravel bottom
Bottom: Sandy bottom
Bottom: Muddy bottom
Watercourse line: Straight line
Shade: Sunny, up to 10% shade
Vegetation: Willow
Vegetation: Alder
Cross-channel structures: none
COV StropkovWastewater discharge point
0.0 kmCOV SvidnikWastewater discharge point
0.1 kmCOV StropkovWastewater treatment plant · capacity 12,910 PE
0.2 kmCOV SvidnikWastewater treatment plant · capacity 13,500 PE
0.4 kmNobody has recorded a catch in this fishing district yetBe the first: after approval it will also appear here in the ranking.
Water of below-average suitability for carp and cyprinids
Stream zoneLevel of evidence: Partly supported
Water hardnessLevel of evidence: Hypothesis
Water acidity (pH)Level of evidence: Partly supported
MineralizationLevel of evidence: Hypothesis
Metals in sedimentLevel of evidence: Partly supported
Public data about this water hardly change the activity score.
Water hardnessLevel of evidence: Hypothesis
+1
Surface water quality (SHMÚ)Level of evidence: Anglers' practice
−1
Nitrogen in groundwater (SHMÚ)Level of evidence: Partly supported
−1
Harmful substances in groundwater (SHMÚ)Level of evidence: Partly supported
−1
Aquatic insect hatchesLevel of evidence: Anglers' practice
0
Svidník, aboveOndava, river km 121.5 · 9.7 km from the fishing district
no unmet standard2022202320242025
Indicator2022202320242025
Nutrients and nitrogen
nitrites●standard not met●standard not met●standard not met·standard met
Harmful organic substances
AOX (adsorbable organic halogens)·standard met●standard not met·standard met·standard met
MinovceStropkov district · borehole or well · 0.1 km from the fishing district
substances from human activity2017 to 2025
DuplinStropkov district · borehole or well · 0.2 km from the fishing district
natural substances only2017 to 2025
Bukovce – pri KaplnkeStropkov district · spring · 0.2 km from the fishing district
no exceedance in 20252017 to 2025
MinovceStropkov district · borehole or well · 0.5 km from the fishing district
natural substances only2017 to 2025
Stropkov-sitnikStropkov district · borehole or well · 0.5 km from the fishing district
natural substances only2017 to 2025
StrocinSvidník district · borehole or well · 2.3 km from the fishing district
natural substances only2017 to 2025
Vysne Cabiny – Krasny BrodMedzilaborce district · borehole or well · 8.1 km from the fishing district
natural substances only2017 to 2025
COV Stropkov0.2 km from the fishing district · capacity 12,910 PE · mechanical, biological, nitrogen and phosphorus removal
within the standard35% of capacity
COV Svidnik0.4 km from the fishing district · capacity 13,500 PE · mechanical, biological, nitrogen and phosphorus removal
within the standard42% of capacity
Bedrock, stony
Geology
Radon risk
Uranium (eU)
Gamma radiation
Magnetics