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 |
|---|---|---|---|---|---|
| JACKSON CREEK | California | Good | 1948 | 78 | 19,800 |
| SOUTH FORK JACKSON CREEK | California | Good | 1948 | 78 | 10,800 |
| MIDDLE FORK JACKSON CRK | California | Good | 1948 | 78 | 10,800 |
| BOWMAN CANYON | California | Poor | 1948 | 78 | 3,056 |
| PACHECO SLOUGH | California | Poor | 1948 | 78 | 2,409 |
| STANISLAUS RIVER | California | Good | 1948 | 78 | 53,500 |
| LITTLEJOHNS CREEK | California | Fair | 1948 | 78 | 3,681 |
| DELTA-MENDOTA CANAL | California | Fair | 1948 | 78 | 617 |
| STOCKTON DIVERTING CANAL | California | Poor | 1948 | 78 | 6,863 |
| ELMHURST CREEK | California | Fair | 1948 | 78 | 199,000 |
| DAMON SLOUGH | California | Good | 1948 | 78 | 199,000 |
| DAMON SLOUGH | California | Fair | 1948 | 78 | 3,300 |
| EAST CREEK SLOUGH | California | Fair | 1948 | 78 | 221,000 |
| ALAMEDA CREEK | California | Fair | 1948 | 78 | 2,700 |
| SAN LEANDRO CREEK | California | Fair | 1948 | 78 | 10,600 |
| EAST CREEK SLOUGH | California | Fair | 1948 | 78 | 3,347 |
| DELTA-MENDOTA CANAL | California | Poor | 1948 | 78 | 5,100 |
| SINBAD CREEK | California | Fair | 1948 | 78 | 1,000 |
| CALTRAIN UP RR GRAND ONR | California | Poor | 1948 | 78 | 98,000 |
| CALTRAIN UP RR GRAND ONR | California | Poor | 1948 | 78 | 98,000 |
| UP RR SPUR | California | Good | 1948 | 78 | 188,000 |
| SOUTH FORK SAN PEDRO CRK | California | Fair | 1948 | 78 | 6,886 |
| SAN BRUNO CHANNEL | California | Fair | 1948 | 78 | 8,252 |
| PETERS CREEK | California | Fair | 1948 | 78 | 30 |
| APTOS CRK & SPRECKELS DR | California | Good | 1948 | 78 | 78,000 |
| STATE ROUTE 1 | California | Good | 1948 | 78 | 17,316 |
| STATE ROUTE 1 | California | Good | 1948 | 78 | 28,896 |
| NEWELL CREEK | California | Fair | 1948 | 78 | 5,000 |
| SAN LORENZO RIVER | California | Poor | 1948 | 78 | 400 |
| ZAYANTE CREEK | California | Poor | 1948 | 78 | 2,000 |
| DEXTER CREEK | California | Good | 1948 | 78 | 19,600 |
| MARCELLA DITCH | California | Good | 1948 | 78 | 7,800 |
| COYOTE CREEK | California | Good | 1948 | 78 | 1,610 |
| GUADALUPE RIVER | California | Fair | 1948 | 78 | 20,400 |
| LLAGAS CREEK | California | Good | 1948 | 78 | 7,230 |
| RANDOL CREEK | California | Fair | 1948 | 78 | 25,850 |
| SAN FRANCISQUITO CREEK | California | Fair | 1948 | 78 | 5,500 |
| WILDCAT CREEK | California | Good | 1948 | 78 | 12,000 |
| WESTLEY WASTEWAY | California | Good | 1948 | 78 | 3,550 |
| DELTA-MENDOTA CANAL | California | Fair | 1948 | 78 | 2,201 |
| WESTLEY WASTEWAY | California | Fair | 1948 | 78 | 946 |
| DELTA-MENDOTA CANAL | California | Fair | 1948 | 78 | 495 |
| M.I.D. MAIN CANAL | California | Fair | 1948 | 78 | 3,294 |
| M.I.D. MAIN CANAL | California | Fair | 1948 | 78 | 1,000 |
| DELTA-MENDOTA CANAL | California | Fair | 1948 | 78 | 99 |
| HIGH LINE CANAL | California | Fair | 1948 | 78 | 200 |
| HIGH LINE CANAL | California | Fair | 1948 | 78 | 50 |
| LATERAL #6 | California | Fair | 1948 | 78 | 2,249 |
| HIGH LINE CANAL | California | Fair | 1948 | 78 | 204 |
| ESCALADIAN CANAL | California | Fair | 1948 | 78 | 480 |
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.