City charter amended
Creation of single member districts
In 1976 Cárdenas spearheaded a successful campaign to create a single-member district voting system for the San Angelo city commission. The proposed city charter amendment challenged the at-large voting system that the city of San Angelo traditionally used. The change to single-member districts allowed marginalized residents to elect members of their own neighborhood onto the city council. After the measure was overwhelmingly approved by voters in April 1976, Cárdenas was named to a special advisory board tasked with drawing up the boundaries for the newly-created districts. On May 13, 1978, the Rio Vista neighborhood elected Cárdenas to represent District 3 of the San Angelo city commission; she was the first Mexican American woman to serve in this capacity. She eventually served on the city commission (known as the city council since 1979) for three consecutive terms. During that time, Cárdenas pushed for improvements to basic services in her previously-underrepresented district such as paved roads, street lights, and a monthly blood pressure clinic for barrio residents. She was also instrumental in convincing the United States Department of Housing and Urban Development to fund construction of a public housing development for low-income seniors living in the Rio Vista neighborhood. Additionally, in 1981 she coordinated efforts between LULAC, the American G.I. Forum, and Texas Rural Legal Aid to challenge a Tom Green County redistricting plan that threatened to weaken minority voting power. The San Angelo city council unanimously elected her to serve as mayor pro-tem for the 1982–83 term.
Cárdenas’s contributions to the city of San Angelo were recognized on a number of occasions. In 1980 she was the only woman included on a list of the twenty-five most powerful San Angeloans. A panel of local judges selected the list. In 1983 she was named the most powerful woman in San Angelo in a poll conducted by the San Angelo Standard-Times. In 1984 she was nominated for induction into the Texas Women’s Hall of Fame by the Governor’s Commission for Women, and in 1993 she was recognized by the Hispanic Development Division of the San Angelo Chamber of Commerce at their annual “Quest for Success” luncheon. In November 2001 the San Angelo city council named the María Cárdenas U.S. 87 Pedestrian Overpass in her honor. The overpass, which allowed children attending Rio Vista Elementary School to safely cross a major thoroughfare, was built largely due to her efforts. A plaque located by the bridge entrance reads, “The key to her success was her vision, sincere belief in the voice of the people, perseverance and devotion to her cause that gained her the respect and admiration of many.” - Handbook of Texas. Photo from San Angelenos, Arnoldo De Leon