Nevada County Bridge Report Card

Nevada County scores 67 out of 100 on BridgeLookup's Bridge Condition Exposure Score, based on FHWA National Bridge Inventory records.

D67 / 100

Local infrastructure snapshot

Nevada County, California

Nevada County has 137 bridges in the National Bridge Inventory, with 19 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 61,976 daily vehicle crossings.

137Total Bridges

19Poor (13.9%)

55Fair (40.1%)

0Scour-Critical

Quote-Ready Local Facts

13.9%of county bridges are in poor condition, compared with 4.9% statewide and 6.7% nationally.

61,976daily vehicle crossings are on poor-condition bridges in the county.

0bridges are rated scour-critical, or 0.0% of the county bridge inventory.

Copyable Facts for Reporters

BridgeLookup.com gives Nevada County a Bridge Condition Exposure Score of 67/100 (D). The county has 137 bridges in the National Bridge Inventory, including 19 in poor condition and 0 rated scour-critical. Poor-condition bridges carry about 61,976 daily vehicle crossings. Poor condition does not mean unsafe; bridges judged unsafe are closed or restricted by transportation agencies.

Download all county report-card scores as CSV.

How the Score Breaks Down

Factor	Weight	County Value	Penalty
Poor-condition bridge share	40	13.9%	27.7
Poor-condition traffic exposure	25	5.1% of measured traffic	3.8
Scour-critical bridge share	20	0.0%	0.0
Average age vs national baseline	10	52 years vs 48 nationally	1.8
Traffic-data completeness	5	1,222,211 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	13.9%
State Poor-Condition Share	4.9%
National Poor-Condition Share	6.7%
County Scour-Critical Share	0.0%
Average Bridge Age	52 years
Poor-Condition Traffic Exposure	61,976 vehicles/day

Bridges to Watch

Busiest Poor-Condition BridgeInterstate 80 WB over South Yuba River — 12,400 vehicles/day Oldest Listed BridgePurdon Road over South Yuba River — built in 1895 All County BridgesBrowse every bridge record in Nevada County.

Top Bridges to Watch in Nevada County

Bridge	Reason	Condition	Daily Traffic	Year Built
Interstate 80 WB over South Yuba River	Poor condition + traffic exposure	Poor	12,400	1962
Broad ST over Deer Creek	Poor condition + traffic exposure	Poor	8,630	1967
Sacramento ST over State Route 20	Poor condition + traffic exposure	Poor	8,500	1967
Wolf Road (cr 10) over Wolf Creek	Poor condition + traffic exposure	Poor	6,332	1968
Interstate 80 WB over SR 20 Up Rr Bnsf Amtrak	Poor condition + traffic exposure	Poor	5,875	1963
Interstate 80 EB over SR 20 Up Rr Bnsf Amtrak	Poor condition + traffic exposure	Poor	5,875	1963
Penn Valley Drive over Clear Creek	Poor condition + traffic exposure	Poor	5,673	1931
Nevada Street over Deer Creek	Poor condition + traffic exposure	Poor	3,300	1938
Limekiln Road over Wolf Creek	Poor condition + traffic exposure	Poor	2,281	1988
You Bet Road over Greenhorn Creek	Poor condition + traffic exposure	Poor	2,087	1995

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.