Facility Marking

Facility owners should indicate their facilities by placing their initials or name at the beginning & end of locates. Also, arrows should be placed at the end of markings to indicate the underground facility continues.

To avoid confusion on long runs, the marks should be frequent enough to identify the owner.

The marks should indicate the approximate center-line of the underground lines. For example, the middle of the cable, line or pipe should be at the center of the dashed marks.

Location marks should be 4 to 12 inches in length & at intervals of 5 to 10 feet.

The line locator (person marking the lines) should extend marks outside the white lined work area by 20 to 30 feet. The purpose of white lining the area to be located is to allow everyone involved with the dig site to know the exact location of the proposed excavation.

White lining proposed dig sites that will follow a single path or trench could be marked using white lines &/or arrows. It is important to identify the starting & ending points.

If line location marks (excessive paint) would be considered damaging to the landscape or pavement, spots could be used to identify underground lines.

In areas such as flower beds, rock gardens, etc., flags may be an alternative to paint. The decision to use flags, paint, stakes, or whiskers should be based on the terrain & job conditions. For instance, flags & stakes in wet areas, whiskers in dirt construction zones that have a high volume of traffic crossing their line location marks.

Dead ends, stub-outs, termination points, etc., should be marked as follows:

Lines that have lateral connections (T's) or changes in directions should be clearly indicated. Marks that show changes in direction should be placed closer together for more accuracy. Marks indicating lateral connections should clearly show the intersection & path of the lateral.

Manholes valves should be identified by using a circle & letters if they are not visible (dirt covering valve boxes or pavement covering manhole cover).

EMS (Electronic Marker Sensor) markers or buried splices should be marked by placing a circle with a X through it. This symbol will identify the location of line splices or EMS markers.

Facility markings that do not have splices or tie-ins should be marked in a way that would clearly show that the lines cross but do not intersect.

Lines that are spliced or tied in to each other should be marked in a manner that clearly indicates the lines are connected.

When facilities share the same trench, they should be heavily identified & separated enough so that they can be readily identified. This would apply to lines that share the same color code. For example, cable television & telephone lines:

If the width of the facilities dictates that it should be indicated by markings such as certain electrical lines, large water & wastewater lines, they should be identified with a diamond intersected by 3 parallel lines.

If the marking area suggests less paint, the following would be acceptable. Dots can be used in place of lines & diamond symbols.

Duct structures (line packages) should be marked by using a triangle with parallel boundary (edge of duct package) on each side of the triangle.

Single fiber optic lines should be indicated as follows:

Duct structures that involve fiber optic cable should be marked as follows:

In situations where large pipe or other facilities may take up the entire trench width, it may not be possible to place all the line marks parallel to each other. In this case marks should be placed next to the larger structures. This will show that all lines share the same ditch.

If the marking area suggests less paint, the following is acceptable:

In areas where there is a strong likelihood that any or all marker types showing line location would be destroyed, offsets can be placed on a permanent surface. However, offsets should be used only in conjunction with marks placed above a facility. Offset spacing should be every third or fourth mark. For example, the following mark would indicate the line is 16 feet from the end of the arrow.

If it is determined that lines are not in conflict (not in area) with the proposed dig site, positive response is required. This can be done in 1 of 2 ways. Either contact the person proposing the excavation directly or leave information at the site. This is satisfied by writing the line owner's name or initials followed by a slash & "OK". This information should be in a very visible place within the requested dig site.