Historic Bridges in California
4,414 bridges built before 1951 in California still in service today.
Bridges Built Before 1951
The United States has 4,414 bridges in California built before 1951 that remain in active service. These structures are 75+ years old — many predate modern engineering codes and were not designed for today's traffic volumes and vehicle weights. The average design life of a bridge is 50 years, making these aging structures a significant infrastructure concern.
| Bridge | State | Condition | Year Built | Age (Years) | ADT |
|---|---|---|---|---|---|
| DUCK SLOUGH | California | Poor | 1938 | 88 | 360 |
| MARIPOSA CREEK | California | Fair | 1938 | 88 | 384 |
| MILES CREEK | California | Fair | 1938 | 88 | 384 |
| MILES CREEK OVERFLOW | California | Poor | 1938 | 88 | 270 |
| FARMDALE SLOUGH | California | Fair | 1938 | 88 | 270 |
| NORTH FARMDALE SLOUGH | California | Fair | 1938 | 88 | 270 |
| SOUTH FORK KINGS RIVER | California | Fair | 1938 | 88 | 730 |
| FOWLER SWITCH CANAL | California | Fair | 1938 | 88 | 4,200 |
| HERNDON CANAL | California | Fair | 1938 | 88 | 200 |
| HERNDON CANAL | California | Fair | 1938 | 88 | 200 |
| HERNDON CANAL | California | Fair | 1938 | 88 | 110 |
| FOWLER SWITCH CANAL | California | Fair | 1938 | 88 | 800 |
| BIG CREEK | California | Good | 1938 | 88 | 2,000 |
| MURRAY CREEK | California | Good | 1938 | 88 | 95 |
| BEAR CREEK | California | Good | 1938 | 88 | 200 |
| SAND CREEK | California | Good | 1938 | 88 | 275 |
| WEST WALKER RIVER | California | Good | 1938 | 88 | 83 |
| QUIEN SABE CREEK | California | Fair | 1938 | 88 | 1,433 |
| PASO ROBLES CREEK | California | Poor | 1938 | 88 | 151 |
| NOJOQUI CREEK | California | Fair | 1938 | 88 | 11,000 |
| BIG SYCAMORE CREEK | California | Poor | 1938 | 88 | 11,600 |
| LOS ANGELES AQUEDUCT | California | Good | 1938 | 88 | 5,500 |
| EQUESTRIAN ACCESS | California | Good | 1938 | 88 | 130,000 |
| STATE ROUTE 110 | California | Good | 1938 | 88 | 4,000 |
| STATE ROUTE 110 | California | Good | 1938 | 88 | 3,000 |
| COMPTON CRK | California | Fair | 1938 | 88 | 29,362 |
| LACMTA AND SCRRA TRACK | California | Poor | 1938 | 88 | 3,162 |
| VERDUGO WASH | California | Good | 1938 | 88 | 16,624 |
| VERDUGO WASH | California | Good | 1938 | 88 | 5,356 |
| VERDUGO WASH | California | Good | 1938 | 88 | 816 |
| BALLONA CRK | California | Fair | 1938 | 88 | 22,688 |
| BALLONA CR | California | Fair | 1938 | 88 | 7,421 |
| BALLONA CRK | California | Fair | 1938 | 88 | 34,545 |
| COMPTON CRK | California | Poor | 1938 | 88 | 29,520 |
| COMPTON CRK | California | Fair | 1938 | 88 | 36,146 |
| ALHAMBRA WASH | California | Fair | 1938 | 88 | 22,260 |
| COMPTON CRK | California | Poor | 1938 | 88 | 27,136 |
| ARROYO SEQUIT | California | Good | 1938 | 88 | 408 |
| BALLONA CRK | California | Fair | 1938 | 88 | 11,864 |
| BALLONA CREEK | California | Fair | 1938 | 88 | 30,000 |
| HAINES CANYON CHANNEL | California | Fair | 1938 | 88 | 497 |
| LOS ANGELES RIVER | California | Good | 1938 | 88 | 12,650 |
| COMPTON CRK | California | Fair | 1938 | 88 | 11,330 |
| RUBIO WASH | California | Good | 1938 | 88 | 4,080 |
| SANTA CLARA RIV | California | Fair | 1938 | 88 | 17,640 |
| GROUT CREEK | California | Good | 1938 | 88 | 2,300 |
| OSO CREEK | California | Good | 1938 | 88 | 5,800 |
| PRAIRIE CREEK | California | Fair | 1938 | 88 | 21,800 |
| BOMPAS WASH CREEK | California | Good | 1938 | 88 | 10,800 |
| BORGO WASH CREEK | California | Good | 1938 | 88 | 10,800 |
About Historic Bridge Data
Bridges built before 1951 are classified as historic in this database. Many were designed to 1940s standards with lower load limits and narrower lanes. While FHWA requires regular inspections of all bridges regardless of age, older structures often require more frequent monitoring and rehabilitation investment.