Rockdale is a city in Milam County, Texas, United States. The population was 5,440 at the 2000 census. Rockdale is the site of a large Alcoa smelting operation, which can produce 1.67 million pounds of aluminum per day. The ALCOA plant was closed in late 2008 - early 2009. Author George Sessions Perry was born in Rockdale on May 5, 1910, and lived much of his life there.