Hydrography
The hydrographic basin
The total area of the basin is 17,048 km2 and its perimeter is 1,156 km. at its top (Miño Alto)occupies an area of 27% of the total basin. The most relevant tributaries in this area are the Ladra River and the Neira River. In Os Peares there is the confluence of the Miño with its most important tributary: the Sil river, with 7,983 km2 of hydrographic basin (47% of the total basin del Miño) and whose tributaries include: Bibei River, Cúa River, Río Boeza and Cabe River . Downstream of Os Peares(Low Minho), the Miño receives water from the rivers Arnoia, Avia, Tea, Coura and Mouro, among others.
The Spanish part is managed by theMiño-Sil Hydrographic Confederation(CHMS), which also manages the Spanish part of the Limia River hydrographic basin. The Portuguese part is managed by thePortuguese Environmental Agency, inside ofHydrographic Region of Minho and Lima (RH1).
sub-basins
The hydrographic basin of the Miño River has301 sub-basins, in addition to the springs that drain directly into the main canal. 271 belong to Spanish territory, 29 to Portugal and one is shared between both countries,Troncoso or Barxas River.
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Miño Alto area: 88 sub-basins. In this area, the sub-basins with the largest surface area areriver barks(887 km2) andriver Neira(830 km2).
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Silent Zone:120 sub-basins. In itself, the Sil River is the largest sub-basin of the Miño River. Discarding this as a sub-basin, here we find the two largest sub-basins, thebibei river(1,558 km2) and theCua River(1,234 km2).
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Lower Minho area: 93 sub-basins. The largest sub-basins in this area are thearnoia river(742 km2) and theavia river(669 km2).
Of the 301 sub-basins, 49 of them are in the international area (CHIRM), 19 belonging to Spanish territory and 30 to Portugal.
hydrographic network
The drainage network of the basin isdendritic typelike the branches of a tree. The ordination is basically linear, with elongated valleys in which the main river is centered, receiving numerous tributaries on both banks.
TheStrahler's method(1957) classify water lines according to their links. Those that do not have tributaries (headwaters) are assigned an order of 1 (1º order). The ranking increases when two water lines intersect with the same order. For example, two 1st order lines will create one 2nd order, two 2nd order lines will create one 3rd order, and so on.
In the Miño basin there are links of up to 8th order, the Miño River itself throughout its lower section, from its confluence with the Sil River in Os Peares (Ourense).
Altogether, there are23.276 km of water lines.
