Iroquois County Bridge Report Card

Iroquois County scores 56 out of 100 on BridgeLookup's Bridge Condition Exposure Score, based on FHWA National Bridge Inventory records.

F56 / 100

Local infrastructure snapshot

Iroquois County, Illinois

Iroquois County has 568 bridges in the National Bridge Inventory, with 83 rated poor and 2 rated scour-critical. Its poor-condition share of 14.6% is above the 9.5% statewide average. Poor-condition bridges carry about 85,945 daily vehicle crossings.

568Total Bridges

83Poor (14.6%)

227Fair (40.0%)

2Scour-Critical

Quote-Ready Local Facts

14.6%of county bridges are in poor condition, compared with 9.5% statewide and 6.7% nationally.

85,945daily vehicle crossings are on poor-condition bridges in the county.

2bridges are rated scour-critical, or 0.4% of the county bridge inventory.

Copyable Facts for Reporters

BridgeLookup.com gives Iroquois County a Bridge Condition Exposure Score of 56/100 (F). The county has 568 bridges in the National Bridge Inventory, including 83 in poor condition and 2 rated scour-critical. Poor-condition bridges carry about 85,945 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	14.6%	29.2
Poor-condition traffic exposure	25	18.3% of measured traffic	13.7
Scour-critical bridge share	20	0.4%	0.7
Average age vs national baseline	10	46 years vs 48 nationally	0.0
Traffic-data completeness	5	469,750 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	14.6%
State Poor-Condition Share	9.5%
National Poor-Condition Share	6.7%
County Scour-Critical Share	0.4%
Average Bridge Age	46 years
Poor-Condition Traffic Exposure	85,945 vehicles/day

Bridges to Watch

Busiest Poor-Condition BridgeFai-57 NB over Ic Rr — 9,050 vehicles/day Oldest Listed BridgeTr 2 D over Sheldon Ditch #1 — built in 1900 All County BridgesBrowse every bridge record in Iroquois County.

Top Bridges to Watch in Iroquois County

Bridge	Reason	Condition	Daily Traffic	Year Built
Fai-57 NB over Ic Rr	Poor condition + traffic exposure	Poor	9,050	1967
Fai-57 SB over T.p. & W Rr	Poor condition + traffic exposure	Poor	9,050	1967
Fai-57 SB over West Second ST	Poor condition + traffic exposure	Poor	9,050	1967
Fai-57 NB over Prairie CR	Poor condition + traffic exposure	Poor	9,050	1967
Fai-57 SB over Prairie Creek	Poor condition + traffic exposure	Poor	9,050	1967
Fai-57 SB over Louis Creek	Poor condition + traffic exposure	Poor	8,750	1968
Fai 57 NB over Louis Creek	Poor condition + traffic exposure	Poor	8,750	1968
US 45-52 over Langan CR	Poor condition + traffic exposure	Poor	3,650	1952
US 45 & US 52 over Prairie Creek	Poor condition + traffic exposure	Poor	3,250	1952
Ill 1 over Little Beaver Creek	Poor condition + traffic exposure	Poor	2,000	1918

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.