69th Ave SW over Knife River
Mercer County, North Dakota · rated Fair in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- 69th Ave SW over Knife River in Mercer County, North Dakota, 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 1971, making it 54 years old at the 2025 inventory.
- It carries about 20 vehicles a day (traffic count year 2018).
- Its listed owner is the county highway agency.
- It is one of 43 of the 71 inventoried bridges in Mercer County rated fair (60.6%); 4 (5.6%) 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 July 2024, 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 → (47.20224, -101.95468)
Component ratings
| Component | Rating (2024) | Rating (2025) | FHWA scale meaning |
|---|---|---|---|
| Deck | 5 | 5 | Fair condition |
| Superstructure | 6 | 6 | Satisfactory condition |
| Substructure | 7 | 7 | Good condition |
Bridge details
| Structure | Prestressed concrete multiple box beam |
| Length | about 50 ft |
| Location | 1 West 6 South of Zap |
| NBI structure number | 000000029112250 |
| Condition class | Fair |
| Traffic status (item 41) | Open, no restriction |
| Last inspection (item 90) | July 2024 |
| Inspection interval (item 91) | 24 months |
| Scour (item 113) | U: unknown foundation, not evaluated for scour |
Source: FHWA National Bridge Inventory, 2025 data as reported by the North Dakota department of transportation.
Busiest bridges in Mercer County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| Nd Highway 49 over Creek | 1967 | 3,730 | Fair |
| Nd Highway 49 over Knife River | 2016 | 3,400 | Good |
| Nd Highway 49 over Coyote Creek | 2016 | 2,745 | Good |
| Nd Highway 49 over Brush Creek | 2016 | 2,745 | Good |
| Nd Highway 200 over Knife River Overflow | 1952 | 2,300 | Fair |
| Nd Highway 200 over Knife River | 1966 | 2,280 | Fair |
All bridges nearby: Mercer County, ND bridge conditions · every bridge in Mercer County · North Dakota bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.