I-93 US 4 SB over Merrimack River
Fair Condition67 years old25,801 vehicles/day
Location
| State | New Hampshire |
| County | Merrimack |
| Location | 1.5 Mi N. Jct Rt3 |
| Carries | I-93 US 4 SB |
| Crosses | Merrimack River |
| Coordinates | 43.22949, -71.53643 |
Condition Ratings
| Overall Condition | Fair |
| Deck | 7 (Good) |
| Superstructure | 5 (Fair) |
| Substructure | 5 (Fair) |
| Channel/Waterway | 7 (Good) |
| Scour Critical | 3 — Scour critical |
Physical Characteristics
| Material | Steel Continuous |
| Design | Girder and Floorbeam |
| Total Length | 524.0 ft (159.7 m) |
| Max Span | 188.0 ft (57.3 m) |
| Deck Width | 51.8 ft (15.8 m) |
| Deck Area | 2523.3 sq m |
| Main Spans | 3 |
| Year Built | 1959 (reconstructed 1988) |
Traffic
| Avg Daily Traffic | 25,801 (2023) |
| Truck Traffic | 6% |
| Lanes On Bridge | 2 |
Inspection & Ownership
| Last Inspection | 824 |
| Inspection Frequency | Every 24 months |
| Owner | State Highway Agency |
| Historical Significance | Bridge is not eligible for the National Register |
| Structure Number | 005201360011600 |