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 |
|---|---|---|---|---|---|
| HILLSIDE | California | Fair | 1928 | 98 | 5,425 |
| SAN MATEO CREEK | California | Good | 1928 | 98 | 236,000 |
| TRANSMISSION CANAL | California | Fair | 1928 | 98 | 232,000 |
| RECREATIONAL TRAIL | California | Fair | 1928 | 98 | 35,000 |
| APTOS CREEK | California | Fair | 1928 | 98 | 14,600 |
| UVAS CREEK | California | Fair | 1928 | 98 | 1,040 |
| LITTLE UVAS CREEK | California | Good | 1928 | 98 | 1,040 |
| LLAGAS CREEK | California | Good | 1928 | 98 | 1,220 |
| COYOTE CREEK | California | Good | 1928 | 98 | 5,300 |
| LLAGAS CREEK | California | Good | 1928 | 98 | 780 |
| M.I.D. MAIN CANAL | California | Fair | 1928 | 98 | 1,750 |
| SALADO CREEK | California | Good | 1928 | 98 | 7,550 |
| S SAN JOAQUIN MAIN CANAL | California | Fair | 1928 | 98 | 445 |
| ATWATER CANAL | California | Fair | 1928 | 98 | 1,206 |
| MILES CREEK | California | Fair | 1928 | 98 | 4,650 |
| MILES CREEK | California | Fair | 1928 | 98 | 4,650 |
| MILES CREEK | California | Poor | 1928 | 98 | 4,650 |
| MILES CREEK | California | Fair | 1928 | 98 | 4,650 |
| BIG B DITCH | California | Fair | 1928 | 98 | 2,270 |
| DRY CREEK CANAL | California | Fair | 1928 | 98 | 469 |
| LOS ANGELES AQUEDUCT | California | Good | 1928 | 98 | 12,600 |
| CAYUCOS CREEK | California | Fair | 1928 | 98 | 276 |
| SAN LUIS OBISPO CREEK | California | Fair | 1928 | 98 | 4,927 |
| TORO CREEK | California | Good | 1928 | 98 | 2,000 |
| SANTA MONICA CANYON | California | Fair | 1928 | 98 | 2,600 |
| LITTLE SYCAMORE CREEK | California | Fair | 1928 | 98 | 11,600 |
| RINCON CREEK | California | Good | 1928 | 98 | 76,000 |
| CANADA LARGA | California | Good | 1928 | 98 | 150 |
| CANADA LARGA | California | Good | 1928 | 98 | 150 |
| THACHER CREEK | California | Fair | 1928 | 98 | 900 |
| I-5 | California | Fair | 1928 | 98 | 22,125 |
| LOS ANGELES RIVER | California | Good | 1928 | 98 | 37,326 |
| SANTA CLARA RIV | California | Poor | 1928 | 98 | 30,894 |
| SPTCO ABND | California | Fair | 1928 | 98 | 30,894 |
| LORENA ST & BERNAL AVE | California | Good | 1928 | 98 | 17,480 |
| GAVIN CYN CRK | California | Good | 1928 | 98 | 10,841 |
| SANTA ANITA WASH | California | Fair | 1928 | 98 | 27,242 |
| LOS ANGELES RIVER UP RR | California | Good | 1928 | 98 | 18,808 |
| LOS ANGELES RIV | California | Good | 1928 | 98 | 33,503 |
| OLD TOPANGA CRK | California | Fair | 1928 | 98 | 2,300 |
| BUCK CYN | California | Good | 1928 | 98 | 2,053 |
| OLD TOPANGA CRK | California | Poor | 1928 | 98 | 870 |
| SIERRA MADRE WASH | California | Good | 1928 | 98 | 155 |
| SIERRA MADRE WASH | California | Good | 1928 | 98 | 116 |
| SIERRA MADRE WASH | California | Good | 1928 | 98 | 378 |
| SIERRA MADRE WASH | California | Poor | 1928 | 98 | 408 |
| HILLSIDE | California | Good | 1928 | 98 | 150 |
| ARROYO CANYON | California | Fair | 1928 | 98 | 4,000 |
| SAWPIT WASH | California | Good | 1928 | 98 | 29,916 |
| CARBON CANYON | California | Good | 1928 | 98 | 13,600 |
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.