FHWA NBI 2024 Inspection record Public-domain dataset

HIGHLAND LAKE RD

Carrying HIGHLAND LAKE RD over MOKELUMNE RIVER

3.3 MI S OF S.H. 4, Alpine, California

Data updated May 2026

FHWA NBI record, refreshed with each annual release.

Fair
32 t Inventory load rating

Bridge Snapshot: HIGHLAND LAKE RD

The HIGHLAND LAKE RD bridge in Alpine, California carries HIGHLAND LAKE RD over MOKELUMNE RIVER. It was built in 1989, making it 37 years old today. The structure is built primarily of steel and spans 1 section, stretching 7.0 meters (23 feet) end to end. Daily traffic averages 25 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 superstructure at 7/9, substructure at 5/9. The weakest component sits in fair condition. No reported major component scores in the Poor range under the current federal condition thresholds. Its NBI inventory load rating is 32.4 metric tons.

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

How HIGHLAND LAKE RD compares

▲ 1.1
Load rating vs California average (31.3 t)
Bottom 41%
Lower load rating than 59% of California bridges
32
Bridges in Alpine · 2 in Poor condition
HIGHLAND LAKE RD 32.4 t
California average 31.3 t

Live comparison across California.

Historical Sufficiency Rating

PlainBridge-computed
83.7 / 100 - historical 80–100 band
Structural adequacy /55
45.0
Serviceability /30
29.0
Essentiality /15
14.7
Special reductions
−5.0

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 How the historical reference is calculated.

Condition Ratings

Superstructure
7/9
Good (7–9)
Substructure
5/9
Fair (5–6)
Inventory Load Rating
32.4 t
NBI inventory level (metric tons)
Overall Condition
Fair

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

Structural Details

Year Built
1989
Material
Steel
Number of Spans
1
Structure Length
7.0 m (23 ft)
Owner
County Highway Agency
Avg Daily Traffic
25 vehicles/day
Structure Number
31C0019

Condition Analysis

  • At 7/9, the superstructure (beams and supports above the deck) is in good shape and shows no significant wear.
  • At 5/9, the substructure (piers and abutments) shows fair condition, with minor wear flagged for upkeep.

How to read this record

This page shows what the last federal inspection recorded, not whether HIGHLAND LAKE RD 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 HIGHLAND LAKE RD against other structures in Alpine 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 HIGHLAND LAKE RD?

HIGHLAND LAKE RD in Alpine, California, superstructure rating of 7/9, and substructure rating of 5/9 on the FHWA's 0–9 scale.

How often is HIGHLAND LAKE RD inspected?

HIGHLAND LAKE RD'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 25 vehicles per day.

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

FHWA retired that reported status beginning with the 2018 archive. HIGHLAND LAKE RD is currently shown as Fair condition from its component ratings; that category is not a live closure or safety decision.

What is the inventory load rating for HIGHLAND LAKE RD?

HIGHLAND LAKE RD has an NBI inventory load rating of 32.4 metric tons.

Who is responsible for maintaining HIGHLAND LAKE RD?

HIGHLAND LAKE RD is owned and maintained by County Highway Agency.

How old is HIGHLAND LAKE RD and does age affect safety?

HIGHLAND LAKE RD was built in 1989, making it 37 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.