Twin Sisters Rd over Moose River
Lewis County, New York · rated Poor in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- Twin Sisters Rd over Moose River in Lewis County, New York, is rated in poor condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the superstructure, rated 4 (poor condition) on the 0-9 scale.
- It was built in 1920 and reconstructed in 2005, making it 105 years old at the 2025 inventory.
- It carries about 7 vehicles a day (traffic count year 2018).
- Its listed owner is the county highway agency.
- It is one of 26 of the 169 inventoried bridges in Lewis County rated poor (15.4%); 26 (15.4%) 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 August 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 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 → (43.60786, -75.15682)
Component ratings
| Component | Rating (2024) | Rating (2025) | FHWA scale meaning |
|---|---|---|---|
| Deck | 5 | 5 | Fair condition |
| Superstructure | 4 | 4 | Poor condition |
| Substructure | 4 | 4 | Poor condition |
Bridge details
| Structure | Steel through truss |
| Length | about 118 ft |
| Location | 5.4 Mi NE Potters Corners |
| NBI structure number | 000000003339800 |
| Condition class | Poor |
| Traffic status (item 41) | Posted for load |
| Last inspection (item 90) | August 2024 |
| Inspection interval (item 91) | 12 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 New York department of transportation.
Busiest bridges in Lewis County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| Rte 12 over Mill Creek | 1913 | 11,108 | Fair |
| East State Street over Mill Creek | 1963 | 6,160 | Fair |
| Rte 12 over Mohawk Adirondack & Nort | 1950 | 5,391 | Fair |
| Rte 12 over Whetstone Creek | 1989 | 5,059 | Fair |
| Rte 12 over Roaring Brook | 1989 | 5,059 | Fair |
| Rte 12 over House Creek | 1964 | 4,976 | Good |
All bridges nearby: Lewis County, NY bridge conditions · every bridge in Lewis County · New York bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.