Black Rock Road over Great Seneca Creek
Fair Condition61 years old400 vehicles/day
Location
| State | Maryland |
| County | Montgomery |
| Location | 0.7 Miles North Of Md 28 |
| Carries | Black Rock Road |
| Crosses | Great Seneca Creek |
| Coordinates | 39.12711, -77.31411 |
Condition Ratings
| Overall Condition | Fair |
| Deck | 6 (Satisfactory) |
| Superstructure | 5 (Fair) |
| Substructure | 5 (Fair) |
| Channel/Waterway | 6 (Satisfactory) |
| Scour Critical | 3 — Scour critical |
Physical Characteristics
| Material | Steel |
| Design | Stringer/Multi-beam |
| Total Length | 74.1 ft (22.6 m) |
| Max Span | 39.0 ft (11.9 m) |
| Deck Width | 15.1 ft (4.6 m) |
| Deck Area | 104.0 sq m |
| Main Spans | 2 |
| Year Built | 1965 (reconstructed 1993) |
Traffic
| Avg Daily Traffic | 400 (2024) |
| Truck Traffic | 5% |
| Lanes On Bridge | 1 |
Inspection & Ownership
| Last Inspection | 524 |
| Inspection Frequency | Every 24 months |
| Owner | County Highway Agency |
| Historical Significance | Bridge is not eligible for the National Register |
| Structure Number | 200000M-0047010 |