REVERSE CURVE (3 LANES) Sign Requirements

1. When a REVERSE CURVE (3 LANES) Sign Is Used

Warns of a three-lane reverse-curve alignment ahead — a curve in one direction followed by a curve in the other — such as a multilane lane shift around a work area.

• Three-lane lane shifts around work activity
• Multilane temporary alignment changes / crossovers
• Used with channelizing devices through the shift

2. How and Where It Applies

In the field, W1-4c Reverse Curve (3 lanes) is typically positioned at the advance warning area, ahead of the work. Common deployments include three-lane lane shifts around work activity; multilane temporary alignment changes / crossovers; used with channelizing devices through the shift. Always confirm its size, retroreflective sheeting, spacing, and placement against the CA MUTCD 2026 and the reviewing agency before finalizing the traffic control plan.

3. Placement and Application Notes

Position W1-4c advance warning area, ahead of the work.

• Place the sign where drivers have a clear, unobstructed view on approach.
• Mount at the standard height and setback from the edge of the traveled way.
• Do not mount with other signs on the same post unless space constraints require it.

4. Standard Sizes and Visibility Considerations

Typical minimum: 48" × 48" on conventional roads; 60" × 60" on expressways and freeways.

• Choose size based on roadway speed, sight distance, and mounting location.
• Maintain high retroreflectivity for maximum night and adverse-weather visibility.

5. California Notes

Used where a California work zone shifts three lanes of traffic through a reverse (S) alignment, for example around a median rebuild or a temporary crossover.

6. Common Field or Planning Mistakes

• Sign not shown at the correct advance distance for the posted speed.
• Advance warning sign missing or out of sequence on the TCP.
• Wrong size specified for the roadway classification (conventional vs. expressway).
• Sign sheeting / retroreflectivity class not noted on the plan.