ROAD M1
Carrying ROAD M1 over EEL RIVER
13 MILES NE POTTER VALLEY, Lake, California
Inventory: FHWA NBI 2024 · last ETL August 2026
FHWA NBI record, refreshed with each annual release.
ROAD M1 in Lake, California is rated Poor in the FHWA's 2024 National Bridge Inventory.
Built in 1971, it carries 3 rated components on the inspecting agency's 0-9 scale, and its weakest reported component scores 3. The lowest applicable rating sets the federal condition category, so this Poor result describes the weakest reported component rather than the structure as a whole. No NBI category is a closure decision or a live crossing-safety verdict.
NBI record plate
Structure CA:050854000001001
INTERSTATE-ERA · CONCRETE · SINGLE-SPAN · SUPER-LED · LOCAL-ADT · LOAD-UNK · CAT-POOR
- INTERSTATE-ERA 1950–1979
- CONCRETE Concrete
- SINGLE-SPAN Single span
- SUPER-LED Superstructure-led
- LOCAL-ADT Local ADT
- LOAD-UNK Load unrated
- CAT-POOR Poor
Inspection-sheet codes from this record’s year, material family, spans, controlling component, ADT, inventory load, and NBI category, not a live closure verdict.
Bridge Snapshot: ROAD M1
The ROAD M1 bridge in Lake, California carries ROAD M1 over EEL RIVER. It was built in 1971, making it 55 years old today. The structure is built primarily of concrete and spans 1 section, stretching 92.3 meters (303 feet) end to end. Daily traffic averages 350 vehicles, placing it in the lower-traffic tier of California bridges. It is owned and maintained by U.S. Forest Service.
The latest FHWA inspection records show a deck rating of 7/9, superstructure at 3/9, substructure at 7/9. 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.
How ROAD M1 compares
Age against the county: built in 1971, earlier than 52 of Lake's 129 bridges with a recorded construction year (40%), against a county median build year of 1966. This is one of the newer structures in its county.
Live comparison across California bridges with a recorded inventory load rating (25,538 of 25,848 rated).
Condition Ratings
Full 0–9 scale + sufficiency-rating breakdown: how condition ratings work.
Reported 0–9 component ratings from the FHWA NBI. The highlighted component is the lowest reported input to this record’s current condition category; it is not a closure or live crossing-safety decision.
Lake inventory by recorded NBI category
Exclusive Good/Fair/Poor bands across all 129 bridges in this county. Orthogonal to this structure's component profile above: a county catalog share, not a live crossing-safety verdict.
Structural Details
- Year Built
- 1971
- Material
- Concrete
- Number of Spans
- 1
- Structure Length
- 92.3 m (303 ft)
- Deck Width
- 9.7 m (32 ft)
- Owner
- U.S. Forest Service
- Avg Daily Traffic
- 350 vehicles/day
- Structure Number
- 050854000001001
Condition Analysis
- • The deck (driving surface) rates good at 7/9, with no significant deterioration on file.
- • At 3/9, the superstructure (beams and supports above the deck) is in poor shape, with advanced wear on file for this vintage.
- • At 7/9, the substructure (piers and abutments) is in good shape and shows no significant wear.
Location
Data Source
FHWA National Bridge Inventory (NBI).
FHWA NBI Program ↗How to read this record
ROAD M1 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 ROAD M1 against other structures in Lake 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 ROAD M1?
ROAD M1 in Lake, California has a deck rating of 7/9, superstructure rating of 3/9, and substructure rating of 7/9 on the FHWA's 0–9 scale.
How often is ROAD M1 inspected?
ROAD M1'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 350 vehicles per day.
What does “structurally deficient” mean in older bridge reports?
FHWA retired that reported status beginning with the 2018 archive. ROAD M1 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 ROAD M1?
An inventory load rating is not recorded for ROAD M1.
Who is responsible for maintaining ROAD M1?
ROAD M1 is owned and maintained by U.S. Forest Service.
How old is ROAD M1 and does age affect safety?
ROAD M1 was built in 1971, making it 55 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.
Share this inspection record
Send this source-bounded record or download its data card. An NBI condition category is not a closure or live crossing-safety verdict.
Every figure on PlainBridges is rendered directly from federal source data, no number is typed in by an editor. Component ratings, ADT, and condition category on this page are copied from the NBI record for this structure; no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of 2024 NBI release. NBI condition categories reflect the latest reported inventory record, not a live safety, closure, or travel decision.