Harkins Slough Rd over Watsonville Slough
Santa Cruz County, California · rated Fair in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- Harkins Slough Rd over Watsonville Slough in Santa Cruz County, California, 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 2007, making it 18 years old at the 2025 inventory.
- It carries about 5,000 vehicles a day (traffic count year 2016).
- Its listed owner is a city or municipal highway agency.
- It is one of 83 of the 194 inventoried bridges in Santa Cruz County rated fair (42.8%); 32 (16.5%) are rated poor.
- Its traffic status in the 2025 inventory is open, no restriction (NBI item 41).
- Its class is unchanged from 2024 (fair), but component ratings moved: superstructure 7 to 8, substructure 7 to 8.
- Its most recent inspection on record is dated November 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 → (36.9131, -121.77051)
Component ratings
| Component | Rating (2024) | Rating (2025) | FHWA scale meaning |
|---|---|---|---|
| Deck | 5 | 5 | Fair condition |
| Superstructure | 7 | 8 | Very good condition |
| Substructure | 7 | 8 | Very good condition |
Bridge details
| Structure | Continuous prestressed concrete multiple box beam |
| Length | about 672 ft |
| Location | East of Ohlone Parkway |
| NBI structure number | 36C0165 |
| Condition class | Fair |
| Traffic status (item 41) | Open, no restriction |
| Last inspection (item 90) | November 2024 |
| 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 California department of transportation.
Busiest bridges in Santa Cruz County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| State Route 1 over Emeline Street | 2008 | 130,000 | Fair |
| Water Street over Branciforte Creek | 1924 | 100,000 | Fair |
| State Route 1 over Soquel Creek Wharf Rd | 1947 | 97,000 | Good |
| State Route 1 over Bay Avenue | 1995 | 97,000 | Good |
| State Route 1 over Market Street | 1958 | 88,000 | Good |
| State Route 1 over Branciforte Creek | 1958 | 88,000 | Good |
All bridges nearby: Santa Cruz County, CA bridge conditions · every bridge in Santa Cruz County · California bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.