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Interpretation Letter 3-218(I) Color of Delineators vs. Object Markers

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U.S. Department of Transportation
Federal Highway Administration

1200 New Jersey Avenue, SE.
Washington, D.C. 20590

February 22, 2008

In Reply Refer To: HOTO-1

Mr. Doug Cooper
Project Superintendent
Oxford Construction Company
3200 Palmyra Road
Albany, GA 31701-1221

Dear Mr. Cooper:

Please accept our sincere apology for the delay in replying to your September 18, 2007, letter requesting an official interpretation of the Manual on Uniform Traffic Control Devices (MUTCD) regarding the proper color of delineators used to mark the location of storm drain flared ends within the highway right-of-way. Your letter was inadvertently misplaced and recently found.

You included with your letter a copy of the Georgia Department of Transportation Standard #1120 that references a requirement to install a flexible delineator adjacent to such storm drain flared ends. You indicated that in the past you have used yellow delineators for this purpose but that you have recently been told that such delineators must be white, to match the color of the edge line markings on the outer edge of the roadway, per MUTCD Section 3D.03.

The confusion on this matter apparently stems from terminology and the different intended applications of delineators as opposed to object markers. As noted in Section 3D.01, delineators are intended to be used as guidance devices, to help road users discern the alignment of the roadway at night and during adverse weather, and delineators are considered guidance devices rather than warning devices. They shall be installed in a series to indicate the alignment of the roadway. It is for these reasons that Section 3D.03 specifies that delineators shall match the color of the adjacent edge line.

On the other hand, Section 3C.01 states that object markers are used to mark objects within or adjacent to the roadway that could be obstructions. It is for this reason that object markers (other than end-of-roadway markers) are required to be yellow, consistent with the color of warning signs. Section 3C.03 specifically lists culvert headwalls as objects not in the roadway but sometimes so close to the edge of the road as to need a marker.

The storm drain outlets shown on Georgia standard #1120 appear to be similar in nature to culvert headwalls adjacent to the roadway. The purpose of installing a marker adjacent to the drain outlet would be to mark it as a potential hazard for run-off-road vehicles, not as a part of a system of longitudinal delineation of roadway alignment. As such, it is our interpretation that if a marker is to be used at storm drain flared ends or similar objects adjacent to the roadway, a delineator should not be used but rather a yellow object marker, either Type 2 (minimum 6 inches wide by 12 inches high) or Type 3 (12 inches wide by 36 inches high), as depicted in MUTCD Figure 3C-1, should be used. Such an object marker need not be placed on a rigid support. It could be placed on a flexible support such as called for by the Georgia standard drawing.

Again, we are sorry for the delay in replying, but we trust that this interpretation is helpful. If you have any questions, please contact Mr. Scott Wainwright of our staff by e-mail at or by telephone at 202-366-0857. Please note that we have assigned your request the following official interpretation number and title: "3-218(I) - Color of Delineators vs. Object Markers." Please refer to this number in any future correspondence.

Sincerely yours,

/s/ Robert Arnold

Robert Arnold
Director, Office of Transportation Operations