FHWA NBI 2026 Inspection record Public-domain dataset

TR 355

Carrying TR 355 over MUD CREEK

1.5 MI NE ALPHA, Henry, Illinois

FHWA NBI inspection record for this structure. Condition ratings, inventory load rating, span, deck width, and average daily traffic refresh annually with each NBI release.

Poor
17 t Inventory load rating

Bridge Snapshot: TR 355

The TR 355 bridge in Henry, Illinois carries TR 355 over MUD CREEK. It was built in 1948, making it 78 years old today. The structure is built primarily of concrete continuous and spans 2 sections, stretching 7.0 meters (23 feet) end to end. Daily traffic averages 50 vehicles, placing it in the lower-traffic tier of Illinois bridges. It is owned and maintained by Town/Township Highway Agency, the entity responsible for routine inspections and any needed repairs.

The latest FHWA inspection records show culvert at 4/9 on the 0–9 NBI scale, where 9 is excellent and 0 is failed. The weakest component sits in poor condition, which drives the overall status of this bridge. Because at least one major component scores 4 or lower, the FHWA classifies this bridge as structurally deficient — a maintenance flag, not a closure order. Its NBI inventory load rating is 16.8 metric tons — the load level the structure is rated to carry at inventory (long-term) level.

In a county that maintains hundreds of NBI-tracked bridges, TR 355 is one data point in a Illinois inventory that FHWA inspects on a two-year cycle (more often when ratings fall). Bridge age alone is not a reliable safety signal — a 78-era structure can outperform a newer one when maintenance is consistent, materials are sound, and traffic loads stay within design limits. Use the condition ratings above, the sufficiency score, and the structurally-deficient flag together to read the bridge's real status, and check the linked county and state pages to see how this bridge ranks against its peers.

Every figure on this page comes directly from the Federal Highway Administration National Bridge Inventory (NBI), the public dataset that catalogs more than 617,000 highway bridges across the United States and is updated annually from the records that each state Department of Transportation submits to the FHWA. The condition codes use the standardized FHWA Recording and Coding Guide, the same scale that determines federal eligibility for the Highway Bridge Program and the Surface Transportation Block Grant set-aside for off-system bridges. A "structurally deficient" classification under those federal criteria is a maintenance and funding flag, never a closure order; states keep deficient bridges open with load posting, weight limits, or accelerated inspection cycles until rehabilitation or replacement is funded. See our methodology for refresh cadence and the exact NBI release vintage powering each record.

How TR 355 compares

▼ 17.8
Load rating vs Illinois average (34.6 t)
Bottom 2%
Lower load rating than 98% of Illinois bridges
331
Bridges in Henry · 33 structurally deficient
TR 355 16.8 t
Illinois average 34.6 t

NBI inventory load rating (metric tons) and structural-deficiency status compared across Illinois, computed live from the FHWA NBI.

Condition Ratings

Culvert
4/9
Poor (1–4)
Inventory Load Rating
16.8 t
NBI inventory level (metric tons)
SD Status
Structurally Deficient

Ratings are on a 0–9 scale: 9 = Excellent, 7–8 = Good, 5–6 = Fair, 3–4 = Poor, 0–2 = Critical/Failed. Sufficiency rating (0–100) combines structural adequacy, functional obsolescence, and essentiality.

Structural Details

Year Built
1948
Material
Concrete Continuous
Number of Spans
2
Structure Length
7.0 m (23 ft)
Deck Width
7.3 m (24 ft)
Owner
Town/Township Highway Agency
Avg Daily Traffic
50 vehicles/day
Structure Number
037322200000000

Location

1.5 MI NE ALPHA, Henry, Illinois
41.216969, -90.358136
View on Google Maps ↗

Data Source

Data from the FHWA National Bridge Inventory (NBI). Bridge inspections are required every two years by federal law. Conditions reflect the most recent inspection.

FHWA NBI Program ↗

Frequently Asked Questions

What do the condition ratings mean for TR 355?

Bridge condition ratings use a 0–9 scale set by the Federal Highway Administration (FHWA). Ratings 7–9 indicate good condition with no significant problems. Ratings 5–6 mean fair condition with minor issues. Ratings 3–4 indicate poor condition requiring repair. Ratings 0–2 are critical, meaning the bridge has serious structural problems. TR 355 in Henry, Illinois.

How often is TR 355 inspected?

Federal law requires most highway bridges to be inspected at least every 24 months. Bridges in poor condition or with known issues may be inspected more frequently (every 12 months or less). TR 355 is part of the National Bridge Inventory maintained by the FHWA. With 50 vehicles crossing daily, regular inspection is essential.

What does "structurally deficient" mean for a bridge?

A structurally deficient bridge has at least one major component (deck, superstructure, or substructure) rated 4 or below on the FHWA 0–9 scale. This classification does NOT mean the bridge is unsafe for travel — it means the bridge needs repair, rehabilitation, or eventual replacement. Structurally deficient bridges remain open and are monitored. TR 355 is currently classified as structurally deficient.

What is the inventory load rating for TR 355?

The NBI inventory rating is the load level a bridge is rated to carry for an indefinite period, recorded in metric tons. A lower number means the structure is more load-restricted. TR 355 has an inventory load rating of 16.8 metric tons. It is distinct from the FHWA sufficiency rating, a separate 0–100 funding-eligibility score that this dataset does not include.

Who is responsible for maintaining TR 355?

Bridge ownership and maintenance responsibility varies — bridges may be owned by state DOTs, counties, cities, railroads, or federal agencies. TR 355 is maintained by Town/Township Highway Agency. The FHWA oversees the National Bridge Inventory program and sets inspection standards, but day-to-day maintenance falls to the owning agency. If you notice damage or safety concerns, contact your state DOT or call 911 for emergencies.

How old is TR 355 and does age affect safety?

TR 355 was built in 1948, making it 78 years old. Bridge age alone does not determine safety — condition depends on materials, design, traffic load, maintenance history, and environmental exposure. Many older bridges remain in good condition due to regular maintenance and reconstruction.

Disclaimer: Bridge condition data is from the FHWA NBI and reflects the last reported inspection. A structurally deficient rating does not mean a bridge is closed or unsafe for travel — it indicates the bridge requires repair or replacement. For current closure or safety information, contact your state DOT.

Related

Data sourced from official U.S. government datasets. See our methodology for details. Retrieved and formatted by PlainBridges Editorial