Shasta County Bridge Report Card
Shasta County scores 85 out of 100 on BridgeLookup's Bridge Condition Exposure Score, based on FHWA National Bridge Inventory records.
Shasta County, California
Shasta County has 493 bridges in the National Bridge Inventory, with 11 rated poor and 13 rated scour-critical. Its poor-condition share of 2.2% is at or below the 4.9% statewide average. Poor-condition bridges carry about 44,249 daily vehicle crossings.
Quote-Ready Local Facts
Copyable Facts for Reporters
BridgeLookup.com gives Shasta County a Bridge Condition Exposure Score of 85/100 (B). The county has 493 bridges in the National Bridge Inventory, including 11 in poor condition and 13 rated scour-critical. Poor-condition bridges carry about 44,249 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 | 2.2% | 4.5 |
| Poor-condition traffic exposure | 25 | 1.5% of measured traffic | 1.1 |
| Scour-critical bridge share | 20 | 2.6% | 5.3 |
| Average age vs national baseline | 10 | 59 years vs 48 nationally | 4.3 |
| Traffic-data completeness | 5 | 2,908,211 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 | 2.2% |
| State Poor-Condition Share | 4.9% |
| National Poor-Condition Share | 6.7% |
| County Scour-Critical Share | 2.6% |
| Average Bridge Age | 59 years |
| Poor-Condition Traffic Exposure | 44,249 vehicles/day |
Bridges to Watch
Top Bridges to Watch in Shasta County
| Bridge | Reason | Condition | Daily Traffic | Year Built |
|---|---|---|---|---|
| Interstate 5 over Castle Creek | Poor condition + traffic exposure | Poor | 18,000 | 1960 |
| Interstate 5 over Castle Creek Road | Poor condition + traffic exposure | Poor | 18,000 | 1960 |
| State Route 299 over Whiskey Creek(wskytwn Lk | Poor condition + traffic exposure | Poor | 4,050 | 1961 |
| State Route 89 over Lake Britton | Poor condition + traffic exposure | Poor | 1,700 | 1938 |
| Emily RD over Anderson Creek | Poor condition + traffic exposure | Poor | 958 | 1980 |
| Bridge Bay Road over Interstate 5 | Poor condition + traffic exposure | Poor | 880 | 1968 |
| Sweetbrier AVE over Interstate 5 | Poor condition + traffic exposure | Poor | 400 | 1962 |
| Island Road over Little Tule River | Poor condition + traffic exposure | Poor | 100 | 1950 |
| Middle Creek RD over Middle Creek | Poor condition + traffic exposure | Poor | 61 | 1925 |
| Shotgun Creek over Unnamed Creek | Poor condition + traffic exposure | Poor | 50 | 1946 |
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.