Tristan Markey Rivera, 21, of Irving, Texas, has been missing since August 5, 2007. He was last seen in the floodwaters of the Trinity River in Irving wearing a red t-shirt, plaid shorts, and red and black sneakers. Rivera is described as biracial, 6 feet 0 inches tall, about 220 pounds, with black hair and brown eyes.

Rivera is mentally disabled and has a history of seizures, details that make his disappearance especially worrying. His case is classified as Lost/Injured Missing and remains listed by the Texas Missing Persons Clearinghouse and The Charley Project. Few other facts are available about the circumstances that day beyond that he was last seen in the turbulent floodwaters.

Did anyone who lived near the Trinity River or was on or near the river on August 5, 2007, see Tristan or have information that could help locate him?