County Rd 429 over Wyaconda Rvr
Lewis County, Missouri · rated Poor in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- County Rd 429 over Wyaconda Rvr in Lewis County, Missouri, is rated in poor condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the superstructure, rated 4 (poor condition) on the 0-9 scale.
- It was built in 1910, making it 115 years old at the 2025 inventory.
- It carries about 50 vehicles a day (traffic count year 2024).
- Its listed owner is the county highway agency.
- It is one of 10 of the 172 inventoried bridges in Lewis County rated poor (5.8%); 10 (5.8%) are rated poor.
- Its traffic status in the 2025 inventory is closed to all traffic (NBI item 41).
- Its condition class and component ratings are unchanged from the 2024 inventory.
- Its most recent inspection on record is dated January 2018, 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 → (40.16825, -91.58644)
Component ratings
| Component | Rating (2024) | Rating (2025) | FHWA scale meaning |
|---|---|---|---|
| Deck | 6 | 6 | Satisfactory condition |
| Superstructure | 4 | 4 | Poor condition |
| Substructure | 4 | 4 | Poor condition |
Bridge details
| Structure | Steel through truss |
| Length | about 76 ft |
| Location | S 17 T 62 N R 6 W |
| NBI structure number | 16480 |
| Condition class | Poor |
| Traffic status (item 41) | Closed to all traffic |
| Last inspection (item 90) | January 2018 |
| 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 Missouri department of transportation.
Busiest bridges in Lewis County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| US 61 S over Big Br CR | 1999 | 14,279 | Fair |
| US 61 S over Bland Br Ck | 2005 | 14,279 | Fair |
| US 61 S over Unnamed CR | 2005 | 14,279 | Fair |
| US 61 S over Unnamed CR | 2005 | 14,279 | Fair |
| US 61 S over Artesian Br CR | 2005 | 7,886 | Fair |
| US 61 N over Waconda Rvr | 2001 | 7,505 | Good |
All bridges nearby: Lewis County, MO bridge conditions · every bridge in Lewis County · Missouri bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.