Originally determined eligible by the Keeper of the National Register in 1983 as part of the realignment of State Route 76. Its continued eligibility was confirmed in the 2004 Caltrans Historic Bridge Inventory Update: Concrete Arch Bridges.
The San Luis Rey River Bridge (57 0043Z, formerly 57 0043) is a reinforced-concrete, open-spandrel, fixed, parabolic-arch bridge that features five, two-ribbed arch spans measuring 106 feet each. Decorative features include reinforced-concrete, open arched-window railings. The bridge has been converted to a pedestrian crossing and closed to vehicle traffic when the alignment of State Route 76 was moved. At that time it was renumbered 57 0043Z.
