Greenfield Parkway over Riddle Brook

Hillsborough County, New Hampshire · rated Poor in the 2025 National Bridge Inventory

United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled August 20, 2026

• Greenfield Parkway over Riddle Brook in Hillsborough County, New Hampshire, is rated in poor condition in the 2025 National Bridge Inventory (as of August 20, 2026).
• Its lowest-rated component is the culvert, rated 0 (failed condition, out of service) on the 0-9 scale.
• It was built in 2000, making it 25 years old at the 2025 inventory.
• It carries about 571 vehicles a day (traffic count year 2023).
• Its listed owner is a city or municipal highway agency.
• It is one of 31 of the 385 inventoried bridges in Hillsborough County rated poor (8.1%); 31 (8.1%) 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 → (42.90695, -71.50278)

Component ratings

Bridge details

Source: FHWA National Bridge Inventory, 2025 data as reported by the New Hampshire department of transportation.

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Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.