According to the United States Census Bureau, Rio Vista has a total area of 1.0 square mile (2.7 km2), of which 2.0 acres (7,995 m2), or 0.29%, are water.[5] The city's area drains to the Nolan River, a tributary of the Brazos River.
^Note: the US Census treats Hispanic/Latino as an ethnic category. This table excludes Latinos from the racial categories and assigns them to a separate category. Hispanics/Latinos can be of any race.[7][8]