Bridge conditions in Summit County, Colorado
63 inventoried bridges · 5 rated poor · 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
5 of the 63 bridges the federal inventory lists in Summit County are rated poor; the rest split 16 good and 42 fair.
- 5 of the 63 bridges in Summit County, Colorado, are rated in poor condition (7.9%) in the 2025 National Bridge Inventory, as of .
- 16 bridges (25.4%) are rated good and 42 (66.7%) fair.
- The median Summit County bridge was built in 1979.
- The busiest poor-rated bridge is I 70 Ml Wbnd over Corral Creek (built 1979), carrying about 10,000 vehicles a day.
Good 25.4% · Fair 66.7% · Poor 7.9% of 63 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 |
|---|---|---|---|
| I 70 Ml Wbnd over Corral Creek | 1979 | 10,000 | Poor |
| I 70 Ml Ebnd over Smith Gulch | 1977 | 10,000 | Poor |
| I 70 Ml Ebnd over Guller Gulch | 1977 | 10,000 | Poor |
| E. Keystone Rd. over Snake River | 1978 | 433 | Poor |
| County Road 1813 over Blue River | 1938 | 10 | Poor |
Busiest bridges in the county
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| I 70 Wbnd over Forest Service Road | 2021 | 36,000 | Good |
| I 70 Ebnd over Forest Service Road | 2021 | 36,000 | Good |
| I 70 Ml over County Road | 1977 | 27,000 | Good |
| SH 9 Ml over Tenmile Creek | 1980 | 24,000 | Fair |
| SH 9 Ml over I 70 Ml | 1971 | 24,000 | Fair |
| SH 9 Ml over Pedestrian Underpass | 2023 | 22,287 | Good |
| SH 9 Ml over Blue River | 2013 | 21,000 | Good |
| SH 9 Ml over Blue River | 1982 | 20,000 | Fair |
| SH 9 Ml over Blue River | 2008 | 20,000 | Good |
| I70 Ml Wbnd over SH 9 Ml | 1971 | 20,000 | Fair |
Source: FHWA National Bridge Inventory, 2025. Counts cover inventoried highway bridges over 20 feet; ratings are reported by the state DOT.
All of Colorado: Colorado 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.