SH 3 over St Maries River
Benewah County, Idaho · rated Fair in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- SH 3 over St Maries River in Benewah County, Idaho, is rated in fair condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the deck, rated 6 (satisfactory condition) on the 0-9 scale.
- It was built in 1977, making it 48 years old at the 2025 inventory.
- It carries about 1,700 vehicles a day (traffic count year 2023).
- Its listed owner is the state highway agency.
- It is one of 28 of the 48 inventoried bridges in Benewah County rated fair (58.3%); 3 (6.2%) are rated poor.
- Its traffic status in the 2025 inventory is open, no restriction (NBI item 41).
- Its condition class and component ratings are unchanged from the 2024 inventory.
- Its most recent inspection on record is dated October 2024, on a 24-month routine inspection cycle.
- It is coded scour critical (NBI item 113 = 3): scour critical: foundations unstable for the assessed or calculated scour.
- A fair rating means the lowest-rated major component scores 5 or 6 on FHWA's 0-9 scale: some deterioration or minor section loss, but the structure is sound. It is the middle class, not a warning.
View this bridge on a map → (47.15139, -116.45164)
Component ratings
| Component | Rating (2024) | Rating (2025) | FHWA scale meaning |
|---|---|---|---|
| Deck | 6 | 6 | Satisfactory condition |
| Superstructure | 7 | 7 | Good condition |
| Substructure | 6 | 6 | Satisfactory condition |
Bridge details
| Structure | Prestressed concrete stringer or multi-beam girder |
| Length | about 242 ft |
| Location | @ Santa Ncl |
| NBI structure number | 000000000010115 |
| Condition class | Fair |
| Traffic status (item 41) | Open, no restriction |
| Last inspection (item 90) | October 2024 |
| Inspection interval (item 91) | 24 months |
| Scour (item 113) | 3: scour critical: foundations unstable for the assessed or calculated scour |
Source: FHWA National Bridge Inventory, 2025 data as reported by the Idaho department of transportation.
Busiest bridges in Benewah County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| SH 3 over St Maries R;st Maries Br | 1977 | 7,100 | Fair |
| US 95 over RR Roadbed/no Tracks | 1975 | 5,000 | Fair |
| SH 3 over St Maries RR | 2019 | 4,800 | Good |
| SH 3 over St Joe River | 2019 | 4,800 | Good |
| US 95 over Sheep Creek | 1975 | 3,500 | Fair |
| US 95 over Hangman Creek | 1975 | 3,500 | Fair |
All bridges nearby: Benewah County, ID bridge conditions · every bridge in Benewah County · Idaho bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.