Sixes Bridge Road over Monocacy River
Frederick County, Maryland · rated Fair in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- Sixes Bridge Road over Monocacy River in Frederick County, Maryland, is rated in fair condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the superstructure, rated 5 (fair condition) on the 0-9 scale.
- It was built in 1910 and reconstructed in 1995, making it 115 years old at the 2025 inventory.
- It carries about 207 vehicles a day (traffic count year 2024).
- Its listed owner is the county highway agency.
- It is one of 275 of the 485 inventoried bridges in Frederick County rated fair (56.7%); 14 (2.9%) are rated poor.
- Its traffic status in the 2025 inventory is posted for load (NBI item 41).
- Its condition class and component ratings are unchanged from the 2024 inventory.
- Its most recent inspection on record is dated November 2024, on a 12-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 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 → (39.63021, -77.28839)
Component ratings
| Component | Rating (2024) | Rating (2025) | FHWA scale meaning |
|---|---|---|---|
| Deck | 6 | 6 | Satisfactory condition |
| Superstructure | 5 | 5 | Fair condition |
| Substructure | 5 | 5 | Fair condition |
Bridge details
| Structure | Steel through truss |
| Length | about 240 ft |
| Location | 2.5 Mi S of Keysville Rd |
| NBI structure number | 200000F-0503010 |
| Condition class | Fair |
| Traffic status (item 41) | Posted for load |
| Last inspection (item 90) | November 2024 |
| Inspection interval (item 91) | 12 months |
| Scour (item 113) | 7: scour countermeasures installed |
| Fracture critical (item 92A) | Yes |
Source: FHWA National Bridge Inventory, 2025 data as reported by the Maryland department of transportation.
Busiest bridges in Frederick County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| Is 270 over MD 85 (Buckeystown Pike) | 2020 | 111,550 | Good |
| US 15 & Ramp 8 over Carroll Creek | 1958 | 95,190 | Fair |
| US 15 Nbr over US 40/W. Patrick Street | 1958 | 95,190 | Fair |
| US 15 Sbr over US 40/W. Patrick Street | 1958 | 95,190 | Fair |
| Is 70 Ebr over Md 180 | 1968 | 94,760 | Fair |
| Is 70 Wbr over Md 180 | 1968 | 94,760 | Fair |
All bridges nearby: Frederick County, MD bridge conditions · every bridge in Frederick County · Maryland bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.