Grizzley Island Rd over Hill Slough
Solano County, California · rated Good in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- Grizzley Island Rd over Hill Slough in Solano County, California, is rated in good condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the deck, rated 7 (good condition) on the 0-9 scale.
- It was built in 2009, making it 16 years old at the 2025 inventory.
- It carries about 642 vehicles a day (traffic count year 2010).
- Its listed owner is the county highway agency.
- It is one of 194 of the 374 inventoried bridges in Solano County rated good (51.9%); 24 (6.4%) are rated poor.
- Its traffic status in the 2025 inventory is open, no restriction (NBI item 41).
- Its class is unchanged from 2024 (good), but component ratings moved: substructure 7 to 8.
- Its most recent inspection on record is dated August 2024, on a 48-month routine inspection cycle.
- A good rating means every major component - deck, superstructure, substructure, or culvert - is rated 7 or higher on FHWA's 0-9 scale: no more than minor problems.
View this bridge on a map → (38.22566, -122.02152)
Component ratings
| Component | Rating (2024) | Rating (2025) | FHWA scale meaning |
|---|---|---|---|
| Deck | 7 | 7 | Good condition |
| Superstructure | 7 | 7 | Good condition |
| Substructure | 7 | 8 | Very good condition |
Bridge details
| Structure | Prestressed concrete slab |
| Length | about 188 ft |
| Location | 1.3 Mi S Rte 12 |
| NBI structure number | 23C0262 |
| Condition class | Good |
| Traffic status (item 41) | Open, no restriction |
| Last inspection (item 90) | August 2024 |
| Inspection interval (item 91) | 48 months |
| Scour (item 113) | 5: foundations stable, scour within the limits of the footing or piles |
Source: FHWA National Bridge Inventory, 2025 data as reported by the California department of transportation.
Busiest bridges in Solano County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| Interstate 80 over Dan Wilson Creek | 1951 | 202,000 | Fair |
| Interstate 80 over Suisun Creek | 1932 | 202,000 | Poor |
| Interstate 80 over Green Valley Creek | 1928 | 189,000 | Poor |
| Interstate 80 over Pedestrian Walkway | 1961 | 177,000 | Good |
| Interstate 80 over Alamo Creek | 1936 | 147,000 | Poor |
| Interstate 80 over Interstate 780 | 1958 | 145,000 | Good |
All bridges nearby: Solano County, CA bridge conditions · every bridge in Solano County · California bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.