By means of decree 719 of 1935 register Planadas as the seat of the departamental inspection of police of South of Atá; in 1961, by means of ordenanza 66 gives it greater hierarchy in the administrative order appointing it like special inspection of Planadas, and, in 1966 by means of ordenanza 36 is elevated to category of municipality, separating its territory from Ataco. But later they derogate it, in 1971, by errors of procedure, replacing it by the ordenanza 52, in which it creates the municipality of Planadas, with seat in the population of the same name.