T-390 Co. Br #21 over Mahoning Creek
Montour County, Pennsylvania · rated Fair in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- T-390 Co. Br #21 over Mahoning Creek in Montour County, Pennsylvania, is rated in fair condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the superstructure, rated 6 (satisfactory condition) on the 0-9 scale.
- It was built in 1974, making it 51 years old at the 2025 inventory.
- It carries about 50 vehicles a day (traffic count year 2023).
- Its listed owner is the county highway agency.
- It is one of 48 of the 108 inventoried bridges in Montour County rated fair (44.4%); 6 (5.6%) 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 May 2023, on a 24-month routine inspection cycle.
- 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 → (41.00189, -76.61049)
Component ratings
| Component | Rating (2024) | Rating (2025) | FHWA scale meaning |
|---|---|---|---|
| Deck | 7 | 7 | Good condition |
| Superstructure | 6 | 6 | Satisfactory condition |
| Substructure | 7 | 7 | Good condition |
Bridge details
| Structure | Prestressed concrete multiple box beam |
| Length | about 41 ft |
| Location | 0.9 Mi W of Kaseville |
| NBI structure number | 000000000028457 |
| Condition class | Fair |
| Traffic status (item 41) | Open, no restriction |
| Last inspection (item 90) | May 2023 |
| Inspection interval (item 91) | 24 months |
| Scour (item 113) | 7: scour countermeasures installed |
Source: FHWA National Bridge Inventory, 2025 data as reported by the Pennsylvania department of transportation.
Busiest bridges in Montour County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| I-80 Ebl over over S.R. 3013 | 1962 | 14,014 | Fair |
| I-80 Ebl over over Chillisquaque Creek | 1962 | 14,014 | Good |
| I-80 EB over over SR 3003 | 1963 | 14,014 | Fair |
| I-80 EB over over Branch Beaver Run | 1962 | 14,014 | Good |
| I-80 EB over Trib Mauses CR & SR 3007 | 1963 | 14,014 | Fair |
| I-80 WB over over S.R. 3013 | 1962 | 13,626 | Good |
All bridges nearby: Montour County, PA bridge conditions · every bridge in Montour County · Pennsylvania bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.