170TH ST (SDB)
Carrying 170TH ST (SDB) over DRAINAGE
1.0 mi N of jct IA 3, Plymouth, Iowa
Data updated May 2026
FHWA NBI record, refreshed with each annual release.
Bridge Snapshot: 170TH ST (SDB)
The 170TH ST (SDB) bridge in Plymouth, Iowa carries 170TH ST (SDB) over DRAINAGE. It was built in 2004, making it 22 years old today. The structure is built primarily of concrete and spans 1 section, stretching 8.8 meters (29 feet) end to end. Daily traffic averages 469 vehicles, placing it in the lower-traffic tier of Iowa bridges. It is owned and maintained by State Highway Agency.
The latest FHWA inspection records show culvert at 8/9. The weakest component sits in good condition. None of this bridge's reported major components fall into the Poor condition range. Its NBI inventory load rating is 32.7 metric tons.
Sourced from the FHWA National Bridge Inventory. See our methodology for refresh cadence and NBI release vintage.
How 170TH ST (SDB) compares
Live comparison across Iowa.
Historical Sufficiency Rating
PlainBridge-computedFHWA discontinued this calculated item; it does not determine current condition, funding eligibility, posting, or closure. How the historical reference is calculated.
Condition Ratings
Full 0–9 scale + sufficiency-rating breakdown: how condition ratings work.
Structural Details
- Year Built
- 2004
- Material
- Concrete
- Number of Spans
- 1
- Structure Length
- 8.8 m (29 ft)
- Owner
- State Highway Agency
- Avg Daily Traffic
- 469 vehicles/day
- Structure Number
- 000000000274591
Location
Data Source
FHWA National Bridge Inventory (NBI).
FHWA NBI Program ↗How to read this record
This page shows what the last federal inspection recorded, not whether 170TH ST (SDB) is safe to cross today. Here is how to use it.
- NBI condition ratings reflect the latest record in this annual dataset, not a live status. Current routine inspection intervals are risk-based.
- Learn how the 0–9 condition scale and Good/Fair/Poor categories are defined. How condition ratings work
- Compare 170TH ST (SDB) against other structures in Plymouth 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 170TH ST (SDB)?
170TH ST (SDB) in Plymouth, Iowa on the FHWA's 0–9 scale.
How often is 170TH ST (SDB) inspected?
170TH ST (SDB)'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 469 vehicles per day.
What does “structurally deficient” mean in older bridge reports?
FHWA retired that reported status beginning with the 2018 archive. 170TH ST (SDB) is currently shown as Good condition from its component ratings; that category is not a live closure or safety decision.
What is the inventory load rating for 170TH ST (SDB)?
170TH ST (SDB) has an NBI inventory load rating of 32.7 metric tons.
Who is responsible for maintaining 170TH ST (SDB)?
170TH ST (SDB) is owned and maintained by State Highway Agency.
How old is 170TH ST (SDB) and does age affect safety?
170TH ST (SDB) was built in 2004, making it 22 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.
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.