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San Antonio River Tunnel Constructed Categories: 1990-1999, San Antonio River History Timelines: Tricentennial Milestones

Completion of the San Antonio River Flood Tunnel designed to work with the Olmos Dam to protect downtown San Antonio from damage. The project includes an inlet facility located at Josephine Street and the San Antonio River, a 24-foot diameter, 3-mile long tunnel and an outlet site at Lone Star Boulevard. Ten months after completion of the tunnel, on October 17-18, 1998, south central Texas experienced record-breaking rainfall, and both the San Pedro Creek and the San Antonio River tunnels performed as designed, sparing downtown San Antonio from a devastating flood. In 1999, the tunnel project won the State of Texas Outstanding Civil Engineering Achievement Award from the American Society of Civil Engineers; it also received a national-level Award of Merit. A year later, it was one of four projects to receive the Federal Design Achievement Award from the National Endowment for the Arts (NEA), as well as an achievement award from the American Society of Civil Engineers in recognition of the San Antonio River Tunnel Inlet Site.