San Francisco County Bridge Report Card
San Francisco County scores 56 out of 100 on BridgeLookup's Bridge Condition Exposure Score, based on FHWA National Bridge Inventory records.
San Francisco County, California
San Francisco County has 144 bridges in the National Bridge Inventory, with 20 rated poor and 0 rated scour-critical. Its poor-condition share of 13.9% is above the 4.9% statewide average. Poor-condition bridges carry about 1,382,683 daily vehicle crossings.
Quote-Ready Local Facts
Copyable Facts for Reporters
BridgeLookup.com gives San Francisco County a Bridge Condition Exposure Score of 56/100 (F). The county has 144 bridges in the National Bridge Inventory, including 20 in poor condition and 0 rated scour-critical. Poor-condition bridges carry about 1,382,683 daily vehicle crossings. Poor condition does not mean unsafe; bridges judged unsafe are closed or restricted by transportation agencies.
How the Score Breaks Down
| Factor | Weight | County Value | Penalty |
|---|---|---|---|
| Poor-condition bridge share | 40 | 13.9% | 27.8 |
| Poor-condition traffic exposure | 25 | 17.8% of measured traffic | 13.4 |
| Scour-critical bridge share | 20 | 0.0% | 0.0 |
| Average age vs national baseline | 10 | 56 years vs 48 nationally | 3.3 |
| Traffic-data completeness | 5 | 7,760,718 measured daily crossings | 0.0 |
Score = 100 minus weighted penalties. The score is a comparative research signal, not an official safety rating. Read the full methodology.
County Comparisons
| County Poor-Condition Share | 13.9% |
| State Poor-Condition Share | 4.9% |
| National Poor-Condition Share | 6.7% |
| County Scour-Critical Share | 0.0% |
| Average Bridge Age | 56 years |
| Poor-Condition Traffic Exposure | 1,382,683 vehicles/day |
Bridges to Watch
Top Bridges to Watch in San Francisco County
| Bridge | Reason | Condition | Daily Traffic | Year Built |
|---|---|---|---|---|
| U.s. Highway 101 over Cesar Chavez BLVD | Poor condition + traffic exposure | Poor | 234,000 | 1951 |
| I 280 N Al Line over 280/101 Interchange | Poor condition + traffic exposure | Poor | 170,000 | 1960 |
| NB And SB RTE 280 over Lyell Street | Poor condition + traffic exposure | Poor | 170,000 | 1964 |
| I 280 over San Jose & Sickles AVE | Poor condition + traffic exposure | Poor | 166,000 | 1964 |
| 101 And 280 over 280/101 Interchange | Poor condition + traffic exposure | Poor | 153,800 | 1960 |
| Interstate 280 over Alemany BLVD | Poor condition + traffic exposure | Poor | 132,000 | 1966 |
| I 280 - 101s (wu) over 280/101 Interchange | Poor condition + traffic exposure | Poor | 80,000 | 1960 |
| I 280 S Au Line over 280/101 Interchange | Poor condition + traffic exposure | Poor | 80,000 | 1960 |
| S280-s101 Connectr over N101-n280 Connector Ramp | Poor condition + traffic exposure | Poor | 40,000 | 1966 |
| Bayshore BLVD over Route 101 | Poor condition + traffic exposure | Poor | 33,111 | 1970 |
Important safety note
Poor condition does not mean a bridge is unsafe. It means at least one major component has significant deterioration and the bridge is a priority for maintenance, repair, or replacement. Bridges judged unsafe are closed or restricted by transportation agencies.