Trinity County Bridge Report Card
Trinity County scores 82 out of 100 on BridgeLookup's Bridge Condition Exposure Score, based on FHWA National Bridge Inventory records.
Trinity County, California
Trinity County has 194 bridges in the National Bridge Inventory, with 7 rated poor and 9 rated scour-critical. Its poor-condition share of 3.6% is at or below the 4.9% statewide average. Poor-condition bridges carry about 1,080 daily vehicle crossings.
Quote-Ready Local Facts
Copyable Facts for Reporters
BridgeLookup.com gives Trinity County a Bridge Condition Exposure Score of 82/100 (B). The county has 194 bridges in the National Bridge Inventory, including 7 in poor condition and 9 rated scour-critical. Poor-condition bridges carry about 1,080 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 | 3.6% | 7.2 |
| Poor-condition traffic exposure | 25 | 0.9% of measured traffic | 0.7 |
| Scour-critical bridge share | 20 | 4.6% | 9.3 |
| Average age vs national baseline | 10 | 49 years vs 48 nationally | 0.3 |
| Traffic-data completeness | 5 | 115,586 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 | 3.6% |
| State Poor-Condition Share | 4.9% |
| National Poor-Condition Share | 6.7% |
| County Scour-Critical Share | 4.6% |
| Average Bridge Age | 49 years |
| Poor-Condition Traffic Exposure | 1,080 vehicles/day |
Bridges to Watch
Top Bridges to Watch in Trinity County
| Bridge | Reason | Condition | Daily Traffic | Year Built |
|---|---|---|---|---|
| Hyampom Road over Little Creek | Poor condition + traffic exposure | Poor | 330 | 1955 |
| Steiner Flat Road over Dutton Creek | Poor condition + traffic exposure | Poor | 100 | 1950 |
| Price Creek RD over Price Creek | Poor condition + traffic exposure | Poor | 20 | 1950 |
| Summit Creek Road over Carr Creek | Poor condition + traffic exposure | Poor | 300 | 1987 |
| State Route 3 over Coffee Creek Overflow | Poor condition + traffic exposure | Poor | 230 | 1968 |
| May over Rattlesnake Creek | Poor condition + traffic exposure | Poor | 50 | 1959 |
| Wildwood-mad River over Dubakella Creek | Poor condition + traffic exposure | Poor | 50 | 1972 |
| Tule Creek Road over Salt Creek | Scour-critical foundation rating | Good | 670 | 1947 |
| Canyon Creek Road over Clear Gulch | Scour-critical foundation rating | Fair | 75 | 1955 |
| East Fk Hayfork RD over East Fork Hayfork Creek | Scour-critical foundation rating | Fair | 50 | 1965 |
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.