S Mill Grove Road over Yellow Creek
Stephenson County, Illinois · rated Poor in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- S Mill Grove Road over Yellow Creek in Stephenson County, Illinois, is rated in poor condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the deck, rated 4 (poor condition) on the 0-9 scale.
- It was built in 1931, making it 94 years old at the 2025 inventory.
- It carries about 100 vehicles a day (traffic count year 2024).
- Its listed owner is a town or township highway agency.
- It is one of 11 of the 340 inventoried bridges in Stephenson County rated poor (3.2%); 11 (3.2%) are rated poor.
- Its traffic status in the 2025 inventory is posted for load (NBI item 41).
- Its condition class and component ratings are unchanged from the 2024 inventory.
- Its most recent inspection on record is dated December 2023, on a 24-month routine inspection cycle.
- It has fracture-critical members (NBI item 92A): steel tension members without a redundant load path, which get their own scheduled inspections.
- A poor rating means at least one major component - deck, superstructure, or substructure - is rated 4 or lower on FHWA's 0-9 scale. It does not by itself mean the bridge is unsafe; bridges judged unsafe are closed or load-restricted by their owners.
View this bridge on a map → (42.2489, -89.77608)
Component ratings
| Component | Rating (2024) | Rating (2025) | FHWA scale meaning |
|---|---|---|---|
| Deck | 4 | 4 | Poor condition |
| Superstructure | 4 | 4 | Poor condition |
| Substructure | 7 | 7 | Good condition |
Bridge details
| Structure | Steel through truss |
| Length | about 83 ft |
| Location | 3 Mi SE Pearl City |
| NBI structure number | 089318700000000 |
| Condition class | Poor |
| Traffic status (item 41) | Posted for load |
| Last inspection (item 90) | December 2023 |
| Inspection interval (item 91) | 24 months |
| Scour (item 113) | 5: foundations stable, scour within the limits of the footing or piles |
| Fracture critical (item 92A) | Yes |
Source: FHWA National Bridge Inventory, 2025 data as reported by the Illinois department of transportation.
Busiest bridges in Stephenson County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| US 20 EB over Sumner Creek | 1959 | 12,700 | Fair |
| US 20 WB over Wickham Creek | 1983 | 12,700 | Fair |
| US 20WB over Sumner Creek | 1994 | 12,700 | Good |
| US 20 EB over Wickham Creek | 1999 | 12,700 | Fair |
| US 20 & Private Rd over Silver Creek Trib | 1959 | 12,700 | Fair |
| Il 26 over Yellow Creek | 1988 | 12,600 | Fair |
All bridges nearby: Stephenson County, IL bridge conditions · every bridge in Stephenson County · Illinois bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.