Wilton Bridges Show Mix Of Good And Fair Ratings, CTDOT Data Finds

WILTON, CT — Most of Wilton’s bridges are in good structural condition, but several key crossings — including those over the Norwalk River and along Route 33 — received “fair” ratings in recent state inspections, according to data from the Connecticut Department of Transportation.

The CTDOT records show five primary highway bridges in Wilton, carrying U.S. Route 7, Cannon Road, Route 33 and River Gate Drive over various rivers and brooks. While the majority of bridges earned “good” or “very good” scores in their superstructure and substructure components, at least two bridges recorded “fair” ratings, signaling aging elements that warrant increased monitoring.

By contrast, several other bridges — including those on U.S. Route 7 over the Norwalk River — received good or very good evaluations, reflecting solid structural performance under high-traffic conditions.

CTDOT data also shows that most Wilton bridges were built or reconstructed in the 1980s through early 2010s, placing them within the age window where concrete decks and steel elements begin to show predictable wear.

What the National Bridge Inventory Is and How It Classifies Bridges

The National Bridge Inventory is a nationwide database maintained by the Federal Highway Administration that contains detailed structural and condition information on the country’s publicly owned bridges. Every state transportation agency, including the Connecticut Department of Transportation, is required to inspect and report condition ratings for bridges that meet federal criteria.

Which Bridges Are Included in the NBI

A bridge must be included in the NBI if it meets all of the following conditions:

• Has a span of at least 20 feet
• Is publicly owned or located on a public road
• Is inspected at least every 24 months (some more frequently depending on condition)

This includes bridges on interstates, state highways, local roads, and municipal structures.

How the NBI Classifies and Rates Bridges

NBI inspections evaluate several major components of a bridge’s structure. Key elements are assigned numerical condition ratings on a 0–9 scale, where:

• 9 — Excellent
• 8 — Very good
• 7 — Good
• 6 — Fair
• 5 — Poor
• 4 — Serious
• 3 — Critical
• 2 — Imminent failure
• 1 — Failed
• 0 — Gone (no structure remains)

The most important individual ratings are:

• Deck Condition: The physical surface of the bridge that carries traffic — pavement, deck slab, and protective systems.
• Superstructure Condition: The main load-carrying components above the deck, including girders, beams, trusses, and arches.
• Substructure Condition: The supports below the superstructure — abutments, piers, footings, and foundations.
• Culvert Condition: Used for structures that function as culverts rather than traditional bridges.

Overall Classification: “Good,” “Fair,” or “Poor”

FHWA uses these component ratings to classify each bridge:

Good: All major components rated 7 or higher

Fair: One or more components rated 6

Poor: One or more components rated 5 or lower

A bridge classified as “poor” is commonly referred to as structurally deficient, meaning it requires repair or rehabilitation but is not necessarily unsafe.

NBI Ratings are important as they help determine repair priorities for state and federal funding, influence traffic restrictions (e.g., weight limits), and help towns and states assess long-term capital needs.

Wilton Bridge-by-Bridge Snapshot (CTDOT 2025 Inspection Cycle)

Bridge 05477 — U.S. Route 7 over Geotzen Brook

• Deck Rating: Not applicable
• Superstructure Rating: 7 – Good
• Substructure Rating: 7 – Good
• Year Built: 1985
• Year Reconstructed: 2011 Summary: A strong-performing structure along the Route 7 corridor with solid ratings across key components. No significant deterioration noted in recent inspections.

Bridge 04981 — Cannon Road over the Norwalk River

• Deck Rating: 6 – Fair/Satisfactory
• Superstructure Rating: 6 – Fair
• Substructure Rating: 6 – Fair
• Year Built: 1985
• Year Reconstructed: 2011 Summary: One of Wilton’s more weather-exposed crossings, this widely used bridge shows aging on multiple components. CTDOT classifies it as “fair,” meaning it remains safe but should be monitored closely for wear.

Bridge 00532 — U.S. Route 7 over the Norwalk River

• Deck Rating: 7 – Good
• Superstructure Rating: 7 – Good
• Substructure Rating: 7 – Good
• Year Built: 1985
• Year Reconstructed: 2011 Summary: Carries heavy traffic along U.S. Route 7 yet maintains solid “good” ratings across all major components. No immediate concerns recorded.

Bridge 02262 — Route 33 over East Branch Silvermine Brook

• Deck Rating: 6 – Fair/Satisfactory
• Superstructure Rating: 6 – Fair
• Substructure Rating: 6 – Fair
• Year Built: 1985
• Year Reconstructed: 2011 Summary: A key north–south connector, this Route 33 bridge mirrors Cannon Road’s “fair” condition profile. Structural elements are aging, but CTDOT considers the span serviceable with continued monitoring.

Bridge 04355 — River Gate Drive over West Branch Saugatuck River

• Deck Rating: Not applicable
• Superstructure Rating: 7 – Good
• Substructure Rating: 7 – Good
• Year Built: 1985
• Year Reconstructed: 2011 Summary: A stable residential-area crossing showing no significant deterioration in superstructure or substructure elements. Remains in good working condition.

How Wilton Compares to Statewide Trends

CTDOT oversees more than 5,400 roadway bridges statewide, with the average structure now more than 50 years old. About 5 percent are classified as structurally deficient, though Wilton has none in that category based on the most recent inspection cycle.

Still, infrastructure experts warn that even “good” bridges can require increased investment as weather extremes, heavier traffic, and aging components accelerate wear.