FM over Big Slough Drainage Dit.
Muscatine County, Iowa · rated Fair in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- FM over Big Slough Drainage Dit. in Muscatine County, Iowa, is rated in fair condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the deck, rated 5 (fair condition) on the 0-9 scale.
- It was built in 1968, making it 57 years old at the 2025 inventory.
- It carries about 150 vehicles a day (traffic count year 2022).
- Its listed owner is the county highway agency.
- It is one of 62 of the 144 inventoried bridges in Muscatine County rated fair (43.1%); 30 (20.8%) 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 September 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 → (41.50597, -91.30951)
Component ratings
| Component | Rating (2024) | Rating (2025) | FHWA scale meaning |
|---|---|---|---|
| Deck | 5 | 5 | Fair condition |
| Superstructure | 5 | 5 | Fair condition |
| Substructure | 6 | 6 | Satisfactory condition |
Bridge details
| Structure | Continuous concrete slab |
| Length | about 103 ft |
| Location | 077040302 |
| NBI structure number | 000000000257680 |
| Condition class | Fair |
| Traffic status (item 41) | Open, no restriction |
| Last inspection (item 90) | September 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 Muscatine County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| US 61 & Ia 22 over Mad Creek | 1984 | 18,300 | Good |
| US 61 over Hershey Ave | 2008 | 12,100 | Good |
| Isett Ave over Geneva Creek | 1980 | 11,716 | Fair |
| E 2ND St over Mad Creek | 1963 | 8,700 | Fair |
| Ia 38 over Mad Creek | 1972 | 8,200 | Fair |
| Washngton St. over Mad Creek | 1986 | 7,906 | Fair |
All bridges nearby: Muscatine County, IA bridge conditions · every bridge in Muscatine County · Iowa bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.