Bridge conditions in McHenry County, Illinois
227 inventoried bridges · 48 rated poor · 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
Of the 227 McHenry County bridges in the federal inventory, 48 carry a poor rating. That 21.1% share is roughly 3x the national average.
- 48 of the 227 bridges in McHenry County, Illinois, are rated in poor condition (21.1%) in the 2025 National Bridge Inventory, as of .
- 92 bridges (40.5%) are rated good and 87 (38.3%) fair.
- The median McHenry County bridge was built in 1985.
- The busiest poor-rated bridge is US 12 over Nippersink CR Overfl (built 1939), carrying about 11,500 vehicles a day.
Good 40.5% · Fair 38.3% · Poor 21.1% of 227 bridges
Bridges rated poor
Every bridge in the county with a poor rating, busiest first. Poor means a major component is rated 4 or lower on FHWA's 0-9 scale; it is a repair flag, not a closure notice.
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| US 12 over Nippersink CR Overfl | 1939 | 11,500 | Poor |
| Bull Valley Road over Boone Creek | 1969 | 9,300 | Poor |
| US 12 over N Br Nippersink Crk | 1990 | 8,250 | Poor |
| Charles Rd over Slough Creek | 1947 | 6,300 | Poor |
| Algonquin Rd over Spring CR | 1986 | 3,200 | Poor |
| Dartmoor Drive over Boone Creek | 1998 | 2,550 | Poor |
| South St Rd over Franklinville CR | 1983 | 2,050 | Poor |
| CH43 (millstream R over Kishwaukee River | 1964 | 1,700 | Poor |
| CH-43 Millstream R over S Br Kishwaukee Rvr | 1964 | 1,700 | Poor |
| Flat Iron Road over Mokeler Creek | 1950 | 1,550 | Poor |
| Bay Road over Unnamed Tributary | 1980 | 1,550 | Poor |
| Fas-39 (hunter Roa over Little Beaver Creek | 1963 | 1,350 | Poor |
| Barreville Rd over Sleepy Hollow Creek | 1957 | 1,350 | Poor |
| Vander Karr Rd over Br of Nippersink CR | 1981 | 1,350 | Poor |
| Maple Rd. C.h.(t-5 over Trib Coon Creek | 1945 | 1,150 | Poor |
| Oakwood Drive over Boone Creek | 1971 | 1,150 | Poor |
| Melody Lane over Silver Creek | 1984 | 1,050 | Poor |
| North Union Road over Kishwaukee River | 1959 | 875 | Poor |
| Marengo Road over Rush Creek | 1956 | 850 | Poor |
| TR-73 (Allendale R over Nippersink CR | 1978 | 850 | Poor |
| Thayer Road over Nippersink Creek | 1975 | 800 | Poor |
| Perkins Rd over Franklinville CR | 1980 | 725 | Poor |
| Harmony Road over Coon Creek | 1980 | 725 | Poor |
| Haegers Bend Rd over Fox Riv Inlet | 1986 | 650 | Poor |
| MS-1000 QueenAnneR over Nippersink | 1960 | 575 | Poor |
| Queen Anne Rd over Br of Nippersink CR | 1960 | 575 | Poor |
| MS-3020 Center St over Stream | 1991 | 575 | Poor |
| County Line Rd over Piscasaw Creek | 1959 | 475 | Poor |
| County Line Rd over Kishwaukee Overflow | 1978 | 475 | Poor |
| Lake View Drive over Island Lake | 1975 | 450 | Poor |
| Streit Road over Piscasaw Creek | 1959 | 425 | Poor |
| Mccue Road over Kishwaukee River | 1973 | 400 | Poor |
| Graf Road over Piscasaw Creek | 1998 | 375 | Poor |
| Frohling Rd over S Br Kishwaukee | 1978 | 325 | Poor |
| Pleasant Valley Rd over Kishwaukee River | 1978 | 325 | Poor |
| Pioneer Rd over Nippersink Creek | 1982 | 325 | Poor |
| FAU-165 (W Solon R over N Br Nippersink Cr | 1983 | 325 | Poor |
| Ch-27 (johnson Rd) over Nippersink CR | 1978 | 300 | Poor |
| Thorne Rd over Kishwaukee Riv | 1992 | 275 | Poor |
| Paulsen Rd over N Br Kishwaukee Riv | 1959 | 250 | Poor |
| Murray Road over Slough Creek | 1968 | 225 | Poor |
| North Union Road over Kishwaukee River | 1973 | 200 | Poor |
| Sullivan Road over Trib N Br Kiswke Riv | 1965 | 100 | Poor |
| Bunker Hill Road over Rush Creek | 1962 | 100 | Poor |
| Bunker Hill Road over Drainage Ditch | 1970 | 100 | Poor |
| Root Road over Rush Creek | 1900 | 100 | Poor |
| Kunde Rd over Kishwaukee River | 1985 | 75 | Poor |
| White Oaks Rd over W Branch Piscasaw CR | 1947 | 50 | Poor |
Busiest bridges in the county
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| Il 62 over Fox River | 1988 | 43,100 | Fair |
| Il 31 over RR - UP | 1971 | 34,400 | Fair |
| Algonquin Road over Woods Creek | 2004 | 31,600 | Fair |
| Algonquin Road over Crystal Creek | 2004 | 31,600 | Fair |
| Algonquin Road over Gravel Pit Creek | 2004 | 31,600 | Fair |
| Rakow Rd (ch V-29) over Crystal Creek | 1994 | 30,600 | Good |
| Il 31 & 120 over Boone Creek | 1990 | 30,300 | Good |
| I-90 WB over Coon Creek | 2013 | 29,350 | Good |
| I-90 EB over Coon Creek | 2013 | 29,350 | Good |
| Randall Road over Woods Creek | 1969 | 28,800 | Good |
Source: FHWA National Bridge Inventory, 2025. Counts cover inventoried highway bridges over 20 feet; ratings are reported by the state DOT.
All of Illinois: Illinois bridge conditions by county · every download on the data page.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.