Flor del Rio, TexasFlor del Rio is a census-designated place in Starr County, Texas, United States. It is a new CDP, formed from part of the Los Alvarez CDP prior to the 2010 census, with a population of 122.GeographyFlor del Rio is located at .DemographicsFlor del Rio first appeared as a census designated place in the 2010 U.S. census after being carved out along with 3 other CDPs from the Los Alvarez CDP.EducationThe CDP is within the Roma Independent School District. The zoned elementary school is Delia Gonzalez Garcia Elementary School. Roma High School is the district's sole comprehensive high school.