Southside Bypass over 1 C Ditch
Klamath County, Oregon · rated Fair in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- Southside Bypass over 1 C Ditch in Klamath County, Oregon, is rated in fair condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the substructure, rated 6 (satisfactory condition) on the 0-9 scale.
- It was built in 1979, making it 46 years old at the 2025 inventory.
- It carries about 10,777 vehicles a day (traffic count year 2022).
- Its listed owner is the state highway agency.
- It is one of 139 of the 248 inventoried bridges in Klamath County rated fair (56.0%); 11 (4.4%) 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 February 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 → (42.17366, -121.74476)
Component ratings
| Component | Rating (2024) | Rating (2025) | FHWA scale meaning |
|---|---|---|---|
| Deck | 7 | 7 | Good condition |
| Superstructure | 7 | 7 | Good condition |
| Substructure | 6 | 6 | Satisfactory condition |
Bridge details
| Structure | Prestressed concrete slab |
| Length | about 23 ft |
| Location | 0 |
| NBI structure number | 35C34 424 00340 |
| Condition class | Fair |
| Traffic status (item 41) | Open, no restriction |
| Last inspection (item 90) | February 2024 |
| Inspection interval (item 91) | 24 months |
| Scour (item 113) | 5: foundations stable, scour within the limits of the footing or piles |
Source: FHWA National Bridge Inventory, 2025 data as reported by the Oregon department of transportation.
Busiest bridges in Klamath County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| Or 140 (hwy 020) over Usrs Canal | 1930 | 20,461 | Fair |
| Or 140 (hwy 020) over Link River | 1931 | 19,357 | Fair |
| Or 140 (hwy 020) over City St & UPRR | 1957 | 19,357 | Fair |
| Shasta Way over A Canal | 1979 | 16,068 | Good |
| S Side Bypass over UPRR | 1986 | 11,928 | Fair |
| S Side Bypass over BNSF & Klamath River | 1986 | 11,850 | Good |
All bridges nearby: Klamath County, OR bridge conditions · every bridge in Klamath County · Oregon bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.