IRR CO RD 87
Carrying IRR CO RD 87 over MAMATH SLOUGH
0.5 MI NE CR 91, Modoc, California
Data updated May 2026
FHWA NBI record, refreshed with each annual release.
Bridge Snapshot: IRR CO RD 87
The IRR CO RD 87 bridge in Modoc, California carries IRR CO RD 87 over MAMATH SLOUGH. It was built in 1955, making it 71 years old today. The structure is built primarily of concrete and spans 1 section, stretching 7.0 meters (23 feet) end to end. Daily traffic averages 255 vehicles, placing it in the lower-traffic tier of California bridges. It is owned and maintained by County Highway Agency.
The latest FHWA inspection records show a deck rating of 7/9, superstructure at 7/9, substructure at 7/9. 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 34.0 metric tons.
Sourced from the FHWA National Bridge Inventory. See our methodology for refresh cadence and NBI release vintage.
How IRR CO RD 87 compares
Live comparison across California.
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 How the historical reference is calculated.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
- 1955
- Material
- Concrete
- Number of Spans
- 1
- Structure Length
- 7.0 m (23 ft)
- Deck Width
- 8.8 m (29 ft)
- Owner
- County Highway Agency
- Avg Daily Traffic
- 255 vehicles/day
- Structure Number
- 03C0071
Location
Data Source
FHWA National Bridge Inventory (NBI).
FHWA NBI Program ↗Condition Analysis
- • The deck (driving surface) is in good condition (7/9), showing no significant deterioration.
- • At 7/9, the superstructure (beams and supports above the deck) is in good shape and shows no significant wear.
- • The substructure (piers and abutments) is in good condition (7/9), showing no significant deterioration.
How to read this record
This page shows what the last federal inspection recorded, not whether IRR CO RD 87 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 IRR CO RD 87 against other structures in Modoc and across California. California 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 IRR CO RD 87?
IRR CO RD 87 in Modoc, California has a deck rating of 7/9, superstructure rating of 7/9, and substructure rating of 7/9 on the FHWA's 0–9 scale.
How often is IRR CO RD 87 inspected?
IRR CO RD 87'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 255 vehicles per day.
What does “structurally deficient” mean in older bridge reports?
FHWA retired that reported status beginning with the 2018 archive. IRR CO RD 87 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 IRR CO RD 87?
IRR CO RD 87 has an NBI inventory load rating of 34.0 metric tons.
Who is responsible for maintaining IRR CO RD 87?
IRR CO RD 87 is owned and maintained by County Highway Agency.
How old is IRR CO RD 87 and does age affect safety?
IRR CO RD 87 was built in 1955, making it 71 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.