UTILITY WORK AHEAD Sign Requirements

1. When a UTILITY WORK AHEAD Sign Is Used

Warns that utility work is taking place on or near the roadway ahead, alerting drivers to utility crews, equipment, and possible lane or shoulder impacts.

• Utility maintenance and installation in the right-of-way
• Short-duration and mobile utility operations
• Encroachment-permit work for utility agencies

2. How and Where It Applies

In the field, W21-7 Utility Work Ahead is typically positioned at the advance warning area, ahead of the work. Common deployments include utility maintenance and installation in the right-of-way; short-duration and mobile utility operations; encroachment-permit work for utility agencies. 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 W21-7 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 by utilities and their contractors in California right-of-way for water, power, gas, and communications work that affects the roadway.

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.