FHWA NBI 2024 Inspection record Public-domain dataset

NORTHBROOK DR

Carrying NORTHBROOK DR over DRY CREEK

000000000, Linn, Iowa

Data updated May 2026

FHWA NBI record, refreshed with each annual release.

Poor
26 t Inventory load rating

Bridge Snapshot: NORTHBROOK DR

The NORTHBROOK DR bridge in Linn, Iowa carries NORTHBROOK DR over DRY CREEK. It was built in 1972, making it 54 years old today. The structure is built primarily of concrete continuous and spans 3 sections, stretching 30.5 meters (100 feet) end to end. Daily traffic averages 1,755 vehicles, placing it in the moderately-trafficked tier of Iowa bridges. It is owned and maintained by City/Municipal Highway Agency.

The latest FHWA inspection records show a deck rating of 4/9, superstructure at 4/9, substructure at 6/9. The weakest component sits in poor condition. At least one major component here scores 4 or below, which produces a Poor condition classification under FHWA's current reporting rules. Its NBI inventory load rating is 26.0 metric tons.

Sourced from the FHWA National Bridge Inventory. See our methodology for refresh cadence and NBI release vintage.

How NORTHBROOK DR compares

▼ 4.9
Load rating vs Iowa average (30.9 t)
Bottom 36%
Lower load rating than 64% of Iowa bridges
428
Bridges in Linn · 20 in Poor condition
NORTHBROOK DR 26.0 t
Iowa average 30.9 t

Live comparison across Iowa.

Historical Sufficiency Rating

PlainBridge-computed
51.7 / 100 - historical 50–79.9 band
Structural adequacy /55
24.7
Serviceability /30
15.9
Essentiality /15
14.1
Special reductions
−3.0

FHWA discontinued this calculated item; it does not determine current condition, funding eligibility, posting, or closure. How the historical reference is calculated.

Condition Ratings

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

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

Structural Details

Year Built
1972
Material
Concrete Continuous
Number of Spans
3
Structure Length
30.5 m (100 ft)
Deck Width
9.8 m (32 ft)
Owner
City/Municipal Highway Agency
Avg Daily Traffic
1,755 vehicles/day
Structure Number
000000000500990

Condition Analysis

  • At 4/9, the deck (driving surface) is in poor shape, with advanced wear flagged for priority repair.
  • The superstructure (beams and supports above the deck) rates poor at 4/9, advanced deterioration that should be prioritized for repair.
  • The substructure (piers and abutments) rates fair at 6/9, minor deterioration that routine maintenance should address.

How to read this record

NORTHBROOK DR 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 NORTHBROOK DR against other structures in Linn and across Iowa. Iowa 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 NORTHBROOK DR?

NORTHBROOK DR in Linn, Iowa has a deck rating of 4/9, superstructure rating of 4/9, and substructure rating of 6/9 on the FHWA's 0–9 scale.

How often is NORTHBROOK DR inspected?

NORTHBROOK DR'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 1,755 vehicles per day.

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

FHWA retired that reported status beginning with the 2018 archive. NORTHBROOK DR 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 NORTHBROOK DR?

NORTHBROOK DR has an NBI inventory load rating of 26.0 metric tons.

Who is responsible for maintaining NORTHBROOK DR?

NORTHBROOK DR is owned and maintained by City/Municipal Highway Agency.

How old is NORTHBROOK DR and does age affect safety?

NORTHBROOK DR was built in 1972, making it 54 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

Every figure on PlainBridge is rendered directly from federal source data, no number is typed in by an editor. This page draws directly on federal source data, no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.