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Slovak reservoirs in 3D

Waters with a bottom model: 477
Maximum depth: 51m
Largest area: 3,351ha
Total volume: 1,784million m³

Reservoirs in brief

The portal has a 3D bottom model for 477 still waters, 214 of them reservoirs. VN Orava has the largest area (3,351 ha). The deepest is VN Ružín (51 m). You can switch the model between reservoirs; for each you can lower the water level and look at the bottom, the original river channels and the rocks beneath.

3D model of the bottom: VN Nová Bystrica

Rotate, zoom, lower the water level and see the original river channels under the waterMaximum depth51 mArea183 ha

Reservoir bed

Map from before flooding

Loading the 3D model of the bed…

Maximum depth51 mfrom a map made before flooding

Average depth16 m

Water volume29.9million m³

Water surface area1.83km²

Water level at full level598.5m a.s.l.

Dominant bedMud and organic sediments80 % of the bed area

How the model was made

Water outlineOpenStreetMap (water body boundary). The water surface ends at the outline. Where the terrain behind it is lower than the water level (the plain behind a dam), the model adds the dam body, which the coarse terrain grid does not capture.
Surrounding terrainDigital terrain models DMR 5.0 a DMR 6.0 (two airborne laser scans, GKÚ). At the water the lower of the two applies, so the bed exposed at a lower water level is captured too. The slope of the banks above the water sets the slope below it.
DepthsThe original terrain under the reservoir from 87 spot heights on maps made before flooding: Topographic mapping 1 : 10,000 (1957 – 1971). The slopes below the surface continue at the gradient of the banks.
Original channelsThe axes and widths of the watercourses from before flooding are taken automatically from the 1 : 25,000 map (blue water on the map). The channel is cut into the bed, and when the water level drops, water flows through it again; pools remain in the hollows.
Under the waterPlaces from the pre-flooding map appear in the model as labels above the water. After a click the model flies to the place and tells you how much water is above it. Riečnica, Harvelka
Bed and bedrockGeological map of Slovakia 1 : 50,000 (ŠGÚDŠ); bed type by zones of erosion, transport and deposition of sediments.
Water colourSentinel-2 satellite: turbidity and chlorophyll from the latest image.

Model reliability

Literature
Fishing regulations
Estimate

The bed is the original terrain from spot heights on old topographic maps.

Cross-section of the reservoir

Height is measured from the full level. The thicknesses of the bedrock layers are illustrative; the map shows the surface only.

Hypsographic curve

How the area and volume of water change as the level drops.

Bed and bedrock

Bed by zones of erosion and sediment deposition, bedrock from the geological map.

The bed is the original terrain under the reservoir according to spot heights on topographic maps from the time before flooding. Mud has settled on it since the reservoir was filled, so actual depths tend to be 1 to 2 m smaller. It is not suitable for navigation or diving.

The bed is the original terrain under the reservoir according to spot heights on topographic maps made before flooding. Mud has settled on it over the decades; actual depths may be 1 to 2 m smaller.
The map gives elevations mainly in the original river channel. The shape of the bed from the channel to the banks is tuned so that the volume matches the published volume of the reservoir.
The water level was lowered at the time of the airborne scan and exposed the reservoir bed; in this zone the depth is measured.

Sources

Knowledge & Management of Aquatic Ecosystems (2016), kmae160036, Table 1 (Slovak reservoirs: water level, area and volume at maximum level)
Topographic mapping 1 : 10,000 (1957 – 1971), Ministry of Environment of the Slovak Republic / National Geoportal, CC0 (spot heights of the original terrain before flooding (87 points))
Topographic mapping 1 : 25,000 (1952 – 1957), Ministry of Environment of the Slovak Republic / National Geoportal, CC0 (axes and widths of the original channels (automatic vectorization of blue water on the map))
Hollister, J., Milstead, W. B. (2011): Using GIS to estimate lake volume from limited data. Lake and Reservoir Management 26(3)
Håkanson, L. (1981): A Manual of Lake Morphometry. Springer (wave base, zones of erosion, transport and accumulation)
Surrounding terrain: DMR 5.0, GKÚ Bratislava, CC BY 4.0
Surrounding terrain and exposed bed: DMR 6.0, ÚGKK SR, CC BY 4.0
Water outline: © OpenStreetMap contributors (ODbL)
Geology: © ŠGÚDŠ, geological map of Slovakia 1 : 50,000

Reliability A: pre-flooding map or a published figure.

Open the fishing district VN Nová Bystrica

The largest and deepest reservoirs

Rankings by volume, area and depth. Click a name to switch the model.

Largest water volume

1.VN Liptovská Mara334 mil. m³
2.VN Zemplínska Šírava316 mil. m³
3.VN Orava295 mil. m³
4.VN Domaša174 mil. m³
5.Dunaj č. 3 – zdrž VD (Hrušov – Čunovo)89,7 mil. m³
6.VN Kráľová65,5 mil. m³
7.VN Starina64,6 mil. m³
8.VN Ružín55,5 mil. m³

Largest surface area

1.VN Orava3 351 ha
2.VN Zemplínska Šírava3 265 ha
3.Dunaj č. 3 – zdrž VD (Hrušov – Čunovo)2 681 ha
4.VN Liptovská Mara2 063 ha
5.VN Domaša1 432 ha
6.VN Kráľová1 110 ha
7.VN Nosice570 ha
8.VN Ružín360 ha

Deepest reservoirs

The area comes from the water outline. The volume and depth rankings include only reservoirs where these are known from a pre-flooding map, the literature or the district rules; estimates from the shape of the water are left out.

Vanished villages and hamlets under the water

What the pre-flooding maps show. In the model they appear as labels; after a click you see how much water is above them.Places28

VN Liptovská Mara38 m
- Liptovská Mara
- Paludza
- Parížovce
- Sokolče
- Ráztoky
- Čemice
- Nežitovce
- Sestrč
- Nižné Dechtáre
- Vyšné Dechtáre
Original channels under the water: Váh
VN Orava28 m
- Slanica
VN Domaša25 m
- Veľká Domaša
- Dobrá nad Ondavou
- Trepec
- Kelča
- Valkov
- Petejovce
Original channels under the water: Ondava
VN Starina44 m
- Starina
Original channels under the water: Cirocha, Stružnica
VN Ružín51 m
- Košické Hámre
Original channels under the water: Hornád, Hnilec, Belá, Opátka
VN Nová Bystrica51 m
- Riečnica
- Harvelka
Original channels under the water: Bystrica, Riečnica, Stanov potok
VN Málinec45 m
- Hámor
- Štavica
- Chmelná
Original channels under the water: Ipeľ, Smolná, Prierazka, Zlatno
VN Ružiná19 m
- Ružiná pond
Original channels under the water: Budinský potok
VVN Bešeňová12 m
- Vrbie
- Demčín
Original channels under the water: Váh
VVN Ružín12 m
- Ružín
Original channels under the water: Hornád

The positions come from topographic maps 1 : 25,000 and 1 : 10,000 (National Geoportal, historical maps) and are verified against airborne laser scanning: today the reservoir surface lies where the village stood. Click a reservoir to switch the model.

All reservoirs with a bottom model

From the largest by volume. Each with its area, maximum depth and volume.Reservoirs214

Gravel pits, lakes and ponds with a bottom model

Other still waters whose bottom we can show in 3DWaters263

The 60 largest of 263 are shown. You will find the bottom model of the others on their fishing district page.

How the bottom model is made and how far to trust it

Three reliability levels and the sources the model is built from

No public bottom surveys exist for most Slovak reservoirs. We therefore build the model from several sources and say for each reservoir how far it can be trusted.

Spoľahlivosť A. The bottom is the original terrain from topographic maps made before flooding, or the maximum depth and volume are known from the literature.
Spoľahlivosť B. The maximum depth comes from the fishing district rules; the bottom shape is computed.
Spoľahlivosť C. Depths are an estimate from the slope of the banks and the shape of the water body.

The surrounding terrain comes from airborne laser scanning (DMR 5.0); the Sentinel-2 satellite tracks the colour of the surface and the extent of the water.

Water reservoirs of Slovakia