FHWA NBI 2024 Inspection record Public-domain dataset

PROSPECT HILL ROAD

Carrying PROSPECT HILL ROAD over ROUTE 2

1.0 MI E OF ROUTE 149, Unknown County, Connecticut

Inventory: FHWA NBI 2024 · last ETL August 2026

FHWA NBI record, refreshed with each annual release.

Poor
44 t Inventory load rating Higher than 61% of rated Connecticut bridges

PROSPECT HILL ROAD in Unknown County, Connecticut is rated Poor in the FHWA's 2024 National Bridge Inventory.

Built in 1959, it carries 3 rated components on the inspecting agency's 0-9 scale, and its weakest reported component scores 4. The lowest applicable rating sets the federal condition category, so this Poor result describes the weakest reported component rather than the structure as a whole. No NBI category is a closure decision or a live crossing-safety verdict.

NBI record plate

Structure CT:00395

INTERSTATE-ERA · STEEL · MULTI-SPAN · DECK-LED · LOCAL-ADT · HEAVY-LOAD · CAT-POOR

  • INTERSTATE-ERA 1950–1979
  • STEEL Steel
  • MULTI-SPAN 2 spans
  • DECK-LED Deck-led
  • LOCAL-ADT Local ADT
  • HEAVY-LOAD Heavy load
  • CAT-POOR Poor

Inspection-sheet codes from this record’s year, material family, spans, controlling component, ADT, inventory load, and NBI category, not a live closure verdict.

Bridge Snapshot: PROSPECT HILL ROAD

The PROSPECT HILL ROAD bridge in Unknown County, Connecticut carries PROSPECT HILL ROAD over ROUTE 2. It was built in 1959, making it 67 years old today. The structure is built primarily of steel and spans 2 sections, stretching 53.7 meters (176 feet) end to end. Daily traffic averages 162 vehicles, placing it in the lower-traffic tier of Connecticut bridges. It is owned and maintained by State Highway Agency.

The latest FHWA inspection records show a deck rating of 4/9, superstructure at 6/9, substructure at 5/9. The weakest component sits in poor condition. Because at least one major component scores 4 or lower, this bridge falls in FHWA's Poor condition category. That category is not a closure order.

How PROSPECT HILL ROAD compares

▲ 0.3
Load rating vs Connecticut average (44.1 t; 4,365 rated)
442
Bridges in Unknown County · 23 in Poor condition

Age against the county: built in 1959, earlier than 291 of Unknown County's 442 bridges with a recorded construction year (66%), against a county median build year of 1964. Age is not a defect on its own, but it is the population from which future Poor ratings are drawn.

PROSPECT HILL ROAD 44.4 t
Connecticut average (4,365 rated) 44.1 t

Live comparison across Connecticut bridges with a recorded inventory load rating (4,365 rated).

PROSPECT HILL ROAD vs every rated Connecticut bridge

Inventory load rating (metric tons), FHWA NBI, this state

44 Top 39% higher than 61% of 4,365 bridges

rated Connecticut bridges, bucketed by value

Each bar is a band; taller bars hold more bridges. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count and share, and where it sits relative to this entry.

Source FHWA National Bridge Inventory · August 2026

Condition Ratings

Deck
4/9
Poor (1–4)
Superstructure
6/9
Fair (5–6)
Substructure
5/9
Fair (5–6)
Inventory Load Rating
44.4 t
NBI inventory level (metric tons)
Overall Condition
Poor

Full 0–9 scale + sufficiency-rating breakdown: how condition ratings work.

Reported 0–9 component ratings from the FHWA NBI. The highlighted component is the lowest reported input to this record’s current condition category; it is not a closure or live crossing-safety decision.

Unknown County inventory by recorded NBI category

Exclusive Good/Fair/Poor bands across all 442 bridges in this county. Orthogonal to this structure's component profile above: a county catalog share, not a live crossing-safety verdict.

Structural Details

Year Built
1959
Material
Steel
Number of Spans
2
Structure Length
53.7 m (176 ft)
Deck Width
10.9 m (36 ft)
Owner
State Highway Agency
Avg Daily Traffic
162 vehicles/day
Structure Number
00395

Condition Analysis

  • The deck (driving surface) rates poor at 4/9, with advanced deterioration recorded on the latest inspection.
  • At 6/9, the superstructure (beams and supports above the deck) shows fair condition, with minor wear flagged for upkeep.
  • At 5/9, the substructure (piers and abutments) shows fair condition, with minor wear flagged for upkeep.

How to read this record

PROSPECT HILL ROAD is in the federal Poor condition category. That is a component-based result, not a closure order.

  • NBI condition ratings reflect the latest record in this annual dataset, not a live status. Current routine inspection intervals are risk-based.
  • Understand what Poor condition does and does not mean before drawing conclusions. Poor condition explained
  • Compare PROSPECT HILL ROAD against other structures in Unknown County and across Connecticut. Connecticut bridges
  • Noticed visible damage or a safety concern? Report it to the agency that owns the bridge, or call 911 in an emergency. How to report a bridge

Condition codes come straight from the FHWA National Bridge Inventory and are not a real-time safety judgment. Only the owning agency, a state DOT, county, or other owner, can post, restrict, or close a bridge.

Frequently Asked Questions

What do the condition ratings mean for PROSPECT HILL ROAD?

PROSPECT HILL ROAD in Unknown County, Connecticut has a deck rating of 4/9, superstructure rating of 6/9, and substructure rating of 5/9 on the FHWA's 0–9 scale.

How often is PROSPECT HILL ROAD inspected?

PROSPECT HILL ROAD's responsible agency sets its routine interval under FHWA's risk-based inspection rules; this page does not expose the scheduled interval. It carries about 162 vehicles per day.

What does “structurally deficient” mean in older bridge reports?

FHWA retired that reported status beginning with the 2018 archive. PROSPECT HILL ROAD is currently shown as Poor condition from its component ratings; that category is not a live closure or safety decision.

What is the inventory load rating for PROSPECT HILL ROAD?

PROSPECT HILL ROAD has an NBI inventory load rating of 44.4 metric tons.

Who is responsible for maintaining PROSPECT HILL ROAD?

PROSPECT HILL ROAD is owned and maintained by State Highway Agency.

How old is PROSPECT HILL ROAD and does age affect safety?

PROSPECT HILL ROAD was built in 1959, making it 67 years old.

Disclaimer: Bridge condition data is from the FHWA NBI and reflects the last reported inspection. A Poor condition rating is not a live declaration that a bridge is closed or unsafe for travel. For current closure, posting, or safety information, contact the responsible transportation agency.

Data sourced from the Federal Highway Administration National Bridge Inventory. See our methodology for details. Retrieved and formatted by PlainBridges

Share this inspection record

Send this source-bounded record or download its data card. An NBI condition category is not a closure or live crossing-safety verdict.

XFacebookLinkedInWhatsAppEmail

Every figure on PlainBridges is rendered directly from federal source data, no number is typed in by an editor. Component ratings, ADT, and condition category on this page are copied from the NBI record for this structure; no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of 2024 NBI release. NBI condition categories reflect the latest reported inventory record, not a live safety, closure, or travel decision.