McHenry County Bridge Report Card

McHenry County scores 52 out of 100 on BridgeLookup's Bridge Condition Exposure Score, based on FHWA National Bridge Inventory records.

F52 / 100

Local infrastructure snapshot

McHenry County, Illinois

McHenry County has 227 bridges in the National Bridge Inventory, with 48 rated poor and 4 rated scour-critical. Its poor-condition share of 21.1% is above the 9.5% statewide average. Poor-condition bridges carry about 69,925 daily vehicle crossings.

227Total Bridges

48Poor (21.1%)

87Fair (38.3%)

4Scour-Critical

Quote-Ready Local Facts

21.1%of county bridges are in poor condition, compared with 9.5% statewide and 6.7% nationally.

69,925daily vehicle crossings are on poor-condition bridges in the county.

4bridges are rated scour-critical, or 1.8% of the county bridge inventory.

Copyable Facts for Reporters

BridgeLookup.com gives McHenry County a Bridge Condition Exposure Score of 52/100 (F). The county has 227 bridges in the National Bridge Inventory, including 48 in poor condition and 4 rated scour-critical. Poor-condition bridges carry about 69,925 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	21.1%	40.0
Poor-condition traffic exposure	25	5.9% of measured traffic	4.4
Scour-critical bridge share	20	1.8%	3.5
Average age vs national baseline	10	42 years vs 48 nationally	0.0
Traffic-data completeness	5	1,184,425 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	21.1%
State Poor-Condition Share	9.5%
National Poor-Condition Share	6.7%
County Scour-Critical Share	1.8%
Average Bridge Age	42 years
Poor-Condition Traffic Exposure	69,925 vehicles/day

Bridges to Watch

Busiest Poor-Condition BridgeUS 12 over Nippersink CR Overfl — 11,500 vehicles/day Oldest Listed BridgeRoot Road over Rush Creek — built in 1900 All County BridgesBrowse every bridge record in McHenry County.

Top Bridges to Watch in McHenry County

Bridge	Reason	Condition	Daily Traffic	Year Built
Harmony Road over Coon Creek	Poor condition + traffic exposure	Poor	725	1980
US 12 over Nippersink CR Overfl	Poor condition + traffic exposure	Poor	11,500	1939
Bull Valley Road over Boone Creek	Poor condition + traffic exposure	Poor	9,300	1969
US 12 over N Br Nippersink Crk	Poor condition + traffic exposure	Poor	8,250	1990
Charles RD over Slough Creek	Poor condition + traffic exposure	Poor	6,300	1947
Algonquin RD over Spring CR	Poor condition + traffic exposure	Poor	3,200	1986
Dartmoor Drive over Boone Creek	Poor condition + traffic exposure	Poor	2,550	1998
South ST RD over Franklinville CR	Poor condition + traffic exposure	Poor	2,050	1983
Ch43 (millstream R over Kishwaukee River	Poor condition + traffic exposure	Poor	1,700	1964
Ch-43 Millstream R over S Br Kishwaukee Rvr	Poor condition + traffic exposure	Poor	1,700	1964

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.