N21 over Wood River Trib
Custer County, Nebraska · rated Good in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- N21 over Wood River Trib in Custer County, Nebraska, is rated in good condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the substructure, rated 7 (good condition) on the 0-9 scale.
- It was built in 1962 and reconstructed in 2021, making it 63 years old at the 2025 inventory.
- It carries about 920 vehicles a day (traffic count year 2018).
- Its listed owner is the state highway agency.
- It is one of 178 of the 301 inventoried bridges in Custer County rated good (59.1%); 24 (8.0%) 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: deck 9 to 8.
- Its most recent inspection on record is dated November 2024, on a 24-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 → (41.1234, -99.76025)
Component ratings
| Component | Rating (2024) | Rating (2025) | FHWA scale meaning |
|---|---|---|---|
| Deck | 9 | 8 | Very good condition |
| Superstructure | 8 | 8 | Very good condition |
| Substructure | 7 | 7 | Good condition |
Bridge details
| Structure | Continuous prestressed concrete tee beam |
| Length | about 82 ft |
| Location | 1S Oconto |
| NBI structure number | S021 05160 |
| Condition class | Good |
| Traffic status (item 41) | Open, no restriction |
| Last inspection (item 90) | November 2024 |
| Inspection interval (item 91) | 24 months |
| Scour (item 113) | 8: foundations stable, scour above the top of the footing |
Source: FHWA National Bridge Inventory, 2025 data as reported by the Nebraska department of transportation.
Busiest bridges in Custer County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| N2/n70/n92 over Mud Creek | 1979 | 6,000 | Good |
| N2/n70/n92 over Mud Creek | 1979 | 3,750 | Good |
| N2/n70/n92 over Mud Creek | 1979 | 3,750 | Good |
| N2/n92 over Mud Creek | 1983 | 3,605 | Good |
| N2/n92 over Mud Creek | 1983 | 3,605 | Fair |
| N2/n92 over Mud Creek Tributary | 1935 | 3,605 | Poor |
All bridges nearby: Custer County, NE bridge conditions · every bridge in Custer County · Nebraska bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.