#Two-thirds of the flow in the main channel of the Rio Grande from the measured Rio Conchos, Rio San Diego, Rio San Rodrigo, Rio Escondido, and Rio Salado, and the Arroyo de las Vacas, subject to certain provisions
Rio de Janeiro | Rio Grande do Sul | Rio Grande | Rio de Janeiro (state) | Rio Grande do Norte | Río de la Plata | Rio | Rio Tinto Group | Rio Negro | Natal, Rio Grande do Norte | Rio Tinto | Rio Negro (Amazon) | Rio Grande Valley | Pinar del Río | Río Piedras, Puerto Rico | Rio Branco | Pinar del Río Province | Rio Ferdinand | Universidade Federal do Rio Grande do Sul | Río Negro | Del Rio, Texas | Rio Tinto Alcan | Río Piedras | Río Negro Province | Río Cuarto, Córdoba | Resende, Rio de Janeiro | Río Cuarto | Federal University of Rio de Janeiro | Santa Maria, Rio Grande do Sul | Rio Verde |
Capt. José de Berroterán in 1729 commanded an expedition on behalf of Spain to explore from Mission San Juan Bautista up the Rio Grande to the mouth of the Rio Conchos.