FM over South River
Warren County, Iowa · rated Fair in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- FM over South River in Warren 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 1986, making it 39 years old at the 2025 inventory.
- It carries about 100 vehicles a day (traffic count year 2022).
- Its listed owner is the county highway agency.
- It is one of 88 of the 238 inventoried bridges in Warren County rated fair (37.0%); 48 (20.2%) 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 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 → (41.21162, -93.76846)
Component ratings
| Component | Rating (2024) | Rating (2025) | FHWA scale meaning |
|---|---|---|---|
| Deck | 6 | 6 | Satisfactory condition |
| Superstructure | 7 | 7 | Good condition |
| Substructure | 7 | 7 | Good condition |
Bridge details
| Structure | Prestressed concrete stringer or multi-beam girder |
| Length | about 142 ft |
| Location | 074251704 |
| NBI structure number | 000000000333431 |
| Condition class | Fair |
| Traffic status (item 41) | Open, no restriction |
| Last inspection (item 90) | October 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 Warren County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| I-35 over Drainage Ditch | 1957 | 24,700 | Good |
| I 35 over Broad Horn Creek | 1957 | 21,000 | Fair |
| I-35 over Drainage Ditch | 1958 | 21,000 | Fair |
| Ia 28 over South Middle Creek | 1984 | 18,500 | Good |
| I 35 SB over North River | 2014 | 12,550 | Good |
| I 35 SB over Badger Creek | 2014 | 12,550 | Good |
All bridges nearby: Warren County, IA bridge conditions · every bridge in Warren County · Iowa bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.