Movie name

There is only one way to pronounce the official Spanish name, which is "Rio Bravo."

Grande. Always 'Grande.' [calling it 'Rio Bravo' would confuse it with the Wayne film of that name]

There is no official English name for the river because there is no English Academy to say just what is "correct" English. The French have one, but I think that's a bad idea that probably impedes the development of that language.

As a native Texan (my great great grandfather was with Sam Houston at San Jacinto)but a long time resident of México, I think it depends on which language you're using. In Texas, in English, we always called it "the Ree-o Grand" and that's how the Austin street with that name is pronounced-- but the Spanish name, in Mexico is "Río Bravo."

If you're speaking Spanish, say Río Bravo.If you're in English, Reeo Grand.

John Wayne made a movie with each name.

We have to ask an English major working at Starbucks.