Finding water
Where water gathers
Summary
Shows the valley floors, hollows and flat plain floors around your village where rainwater gathers because of the shape of the land. Computed from Copernicus elevation data (~90 m). Shows where water tends to gather; it is not proof of groundwater.
Around your village
What do the colours on the map say?
- Dark blue: lines and hollows where water gathers. Valley floors, stream beds and closed hollows where rainwater gathers because of the shape of the land.
- Blue: moderate tendency to gather. Valley sides and slightly hollow ground.
- Hatched: flat plain floor. Flat ground with a slope under 0.5%; water spreads out here, and the shape of the land cannot tell where it gathers.
- Blank and dotted: blank is sloping ground with a low tendency; dotted means no data (sea or outside the border).
It shows the first places to look when searching for a pond or cistern site and when researching a well site. Shows where water tends to gather; it is not proof of groundwater. Only an on-site geological survey gives a firm answer.
Method: topographic wetnessCopernicus DEM GLO-90 · ~90 m
Measure: topographic wetness index (TWI) = ln(a / tan β); a is the area draining into a cell divided by the contour width, β is the slope. The larger the value, the more the land tends to gather water at that point.
Computation: multiple-direction flow (Freeman 1991, p = 1.1), slope by the Horn method (at least 0.001). Sinks are filled; closed hollows larger than 1 km² and 2 m drain to their own lowest point (closed basins). Sea and no-data cells count as outlets.
Classes: dark blue = value ≥ 11.98 (top 10% of sloping land cells); blue = 9.83 to 11.98 (the next 15%); hatched = slope under 0.5%, flat plain floor, where the value does not discriminate. Percentiles come from all sloping land cells in Türkiye. The village row gives the shares of cells within 1 km of the village.
Resolution: 3 arc-seconds (~90 m). One square is about 90 m × 90 m; small hollows at field scale do not show.
Limits: flow from outside Türkiye is not included; along the border the value may stay low in large river beds. The measure is only the shape of the surface; it does not know the rock, the soil, irrigation or the depth of groundwater. The "Will I find water on my land?" likelihood does not use it and has not changed.
Source and attribution: Copernicus DEM GLO-90 (ESA, Airbus). produced using Copernicus WorldDEM™-90 © DLR e.V. 2010-2014 and © Airbus Defence and Space GmbH 2014-2018 provided under COPERNICUS by the European Union and ESA; all rights reserved. The organisations in charge of the Copernicus programme by law or by delegation do not incur any liability for any use of the Copernicus WorldDEM™-90. Values and classes computed by the site.
Related: Water sources nearby · Will I find water on my land? (Turkish)