Arroyo Seco Bridge may refer to the following bridges over the Arroyo Seco in California, USA: The Washington Boulevard Bridge The Seco Street Bridge The Colorado Street Bridge (Pasadena, California), a concrete arch road bridge built in Pasadena in 1913 to carry Colorado Boulevard over the Arroyo The Pioneers Bridge, another concrete arch road bridge built immediately north of the Colorado Street Bridge in the 1950s to carry State Route 134 over the Arroyo The La Loma Bridge which carries La Loma Road over the Arroyo The Santa Fe Arroyo Seco Railroad Bridge The California State Route 110 Bridge The York Boulevard Bridge which on the east end becomes Pasadena Avenue; built in 1912 The Interstate 5 Bridge The San Fernando Road Bridge The Avenue 19 Bridge, the last bridge before the Arroyo Seco flows into the Los Angeles River