Construction, or replacement, of bridges during WWII was not without its problems. As most materials were set aside for the war effort, highway departments had to get creative. In California, one of the materials chosen was salvaged railroad rails. This style of rail was in use mostly during the mid-late 1940’s. I haven’t seen it used after 1950, at least not yet. Other state highways in San Diego County have similar bridges, such as State 79 near Santa Ysabel. Most have been replaced or upgraded since construction. This bridge, along State 76 near Bonsall, is slated to be removed when the highway is upgraded to expressway standards on a new alignment in the next couple years.