Mahogany Road over Branch of Silver Creek
Pottawattamie County, Iowa · rated Fair in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- Mahogany Road over Branch of Silver Creek in Pottawattamie County, Iowa, 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 1961, making it 64 years old at the 2025 inventory.
- It carries about 349 vehicles a day (traffic count year 2021).
- Its listed owner is the county highway agency.
- It is one of 288 of the 557 inventoried bridges in Pottawattamie County rated fair (51.7%); 50 (9.0%) 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 June 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 → (41.39035, -95.44733)
Component ratings
| Component | Rating (2024) | Rating (2025) | FHWA scale meaning |
|---|---|---|---|
| Deck | 6 | 6 | Satisfactory condition |
| Superstructure | 6 | 6 | Satisfactory condition |
| Substructure | 6 | 6 | Satisfactory condition |
Bridge details
| Structure | Continuous concrete slab |
| Length | about 103 ft |
| Location | 076401603 |
| NBI structure number | 000000000287990 |
| Condition class | Fair |
| Traffic status (item 41) | Open, no restriction |
| Last inspection (item 90) | June 2023 |
| 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 Iowa department of transportation.
Busiest bridges in Pottawattamie County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| I-480 & US 6 over Missouri River & RR | 1966 | 53,700 | Fair |
| I-80 EB over Missouri River Rd & RR | 1972 | 31,550 | Fair |
| I 80 & US 6 over Little Mosquito Creek | 1966 | 31,100 | Fair |
| I 80 WB over Missouri Rvr Rd RR | 2010 | 25,250 | Good |
| I 29 SB over I-80 & I-29 Interchange | 2014 | 23,900 | Good |
| I-80 over Bedell Creek | 1965 | 23,800 | Fair |
All bridges nearby: Pottawattamie County, IA bridge conditions · every bridge in Pottawattamie County · Iowa bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.