US 3 over Lost River
Grafton County, New Hampshire · rated Poor in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- US 3 over Lost River in Grafton County, New Hampshire, is rated in poor condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the deck, rated 4 (poor condition) on the 0-9 scale.
- It was built in 1931, making it 94 years old at the 2025 inventory.
- It carries about 2,784 vehicles a day (traffic count year 2023).
- Its listed owner is the state highway agency.
- It is one of 43 of the 547 inventoried bridges in Grafton County rated poor (7.9%); 43 (7.9%) are rated poor.
- A poor rating means at least one major component - deck, superstructure, or substructure - is rated 4 or lower on FHWA's 0-9 scale. It does not by itself mean the bridge is unsafe; bridges judged unsafe are closed or load-restricted by their owners.
View this bridge on a map → (44.02575, -71.68507)
Component ratings
| Component | Rating (2025) | FHWA scale meaning |
|---|---|---|
| Deck | 4 | Poor condition |
| Superstructure | 4 | Poor condition |
| Substructure | 4 | Poor condition |
Bridge details
| Structure | Concrete deck arch |
| Length | about 68 ft |
| Location | 5.6 Mi From Thornton Tl |
| NBI structure number | 028401710015300 |
| Condition class | Poor |
Source: FHWA National Bridge Inventory, 2025 data as reported by the New Hampshire department of transportation.
Busiest bridges in Grafton County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| I-89 NB over Plaza Connector Road | 2012 | 28,690 | Fair |
| I-89 Nh 10 over Brook Atv Trail | 1959 | 25,062 | Fair |
| I-89 Nh 10 NB over Truck Road Mascoma River | 1966 | 23,084 | Fair |
| I-89 NB over US 4 Nh 10 | 1966 | 22,727 | Good |
| I-89 NB over Connecticut River Necrr | 1966 | 22,288 | Poor |
| I-89 Nh 10 SB over US 4 | 1966 | 21,937 | Good |
All bridges nearby: Grafton County, NH bridge conditions · every bridge in Grafton County · New Hampshire bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.