Bridge conditions in Rock County, Wisconsin
304 inventoried bridges · 13 rated poor · 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
13 of the 304 bridges the federal inventory lists in Rock County are rated poor; the rest split 168 good and 123 fair.
- 13 of the 304 bridges in Rock County, Wisconsin, are rated in poor condition (4.3%) in the 2025 National Bridge Inventory, as of .
- 168 bridges (55.3%) are rated good and 123 (40.5%) fair.
- The median Rock County bridge was built in 1997.
- The busiest poor-rated bridge is Ush 51-center Ave over Union Pacific RR (built 1982), carrying about 14,600 vehicles a day.
Good 55.3% · Fair 40.5% · Poor 4.3% of 304 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 |
|---|---|---|---|
| Ush 51-center Ave over Union Pacific RR | 1982 | 14,600 | Poor |
| Sth 213-4th St over Rock River | 1962 | 5,700 | Poor |
| Cth N over Otter Creek | 1964 | 1,461 | Poor |
| Cth J over Turtle Creek Overflow | 1953 | 1,036 | Poor |
| Lrd Lathers Rd over Turtle Creek | 1887 | 474 | Poor |
| Lrd Creek Rd over Turtle Creek | 1957 | 398 | Poor |
| Lrd Oriley Rd over Turtle Creek | 1963 | 293 | Poor |
| Cth J over Little Turtle Creek | 1976 | 272 | Poor |
| Lrd Caledonia Rd over Yahara River | 1966 | 215 | Poor |
| Lrd Milton Shopier over Br Blackhawk Creek | 1923 | 165 | Poor |
| Lrd Nelson Rd over Sugar River | 1958 | 119 | Poor |
| Lrd Tarrant Rd over Blackhawk Creek | 1989 | 105 | Poor |
| Lrd Cleophas Rd over Raccoon Creek | 1918 | 82 | Poor |
Busiest bridges in the county
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| Ih 39 /ih 90 over Br Rock River | 2018 | 57,700 | Good |
| Ih 39 SB / Ih 90 E over Spring Brook / Spring Br | 2019 | 38,500 | Good |
| Ih 39 NB / Ih 90 W over Spring Brook / Spring Br | 2018 | 38,500 | Good |
| Ih 39 SB / Ih 90 E over Cth O | 2003 | 32,550 | Good |
| Ih 39 NB/90 WB over Cth O/ East Delavan Road | 2004 | 32,550 | Good |
| Ih 39 SB / Ih 90 E over Cnw RR | 2019 | 32,550 | Good |
| Ih 39 NB / Ih 90 W over Cnw/up RR | 2018 | 32,550 | Good |
| Ih 39/90 Sb/eb over Lrd Newville Rd | 2019 | 29,900 | Good |
| Ih 39 SB / Ih 90 E over Lrd Kennedy Rd & Bike Pa | 2021 | 29,625 | Good |
| Ih 39 NB / Ih 90 W over Lrd Kennedy Rd | 2020 | 29,625 | Good |
Source: FHWA National Bridge Inventory, 2025. Counts cover inventoried highway bridges over 20 feet; ratings are reported by the state DOT.
All of Wisconsin: Wisconsin 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.