Md 4 over Patuxent River & Town CR
Calvert County, Maryland · rated Fair in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- Md 4 over Patuxent River & Town CR in Calvert 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 1977, making it 48 years old at the 2025 inventory.
- It carries about 28,338 vehicles a day (traffic count year 2023).
- Its listed owner is the state highway agency.
- It is one of 18 of the 34 inventoried bridges in Calvert County rated fair (52.9%); 0 (0.0%) 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 November 2023, on a 24-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 → (38.31861, -76.48491)
Component ratings
| Component | Rating (2024) | Rating (2025) | FHWA scale meaning |
|---|---|---|---|
| Deck | 6 | 6 | Satisfactory condition |
| Superstructure | 5 | 5 | Fair condition |
| Substructure | 6 | 6 | Satisfactory condition |
Bridge details
| Structure | Continuous steel girder and floorbeam |
| Length | about 7,207 ft |
| Location | on St Marys Co Line |
| NBI structure number | 100000040019010 |
| Condition class | Fair |
| Traffic status (item 41) | Open, no restriction |
| Last inspection (item 90) | November 2023 |
| Inspection interval (item 91) | 24 months |
| Scour (item 113) | 5: foundations stable, scour within the limits of the footing or piles |
| Fracture critical (item 92A) | Yes |
Source: FHWA National Bridge Inventory, 2025 data as reported by the Maryland department of transportation.
Busiest bridges in Calvert County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| Md 2 SB over Hunting Creek | 1992 | 46,798 | Fair |
| Md 4 SB over Lyons Creek | 1959 | 46,661 | Fair |
| Md 4 NB over Lyons Creek | 1987 | 46,661 | Fair |
| Md 4 Nbr over Hall Creek | 1966 | 35,171 | Fair |
| Md 2 & 4 over Quaker Swamp | 1987 | 27,798 | Good |
| Md 2 & 4 over Johns Creek | 1987 | 26,941 | Fair |
All bridges nearby: Calvert County, MD bridge conditions · every bridge in Calvert County · Maryland bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.