The existing information shown on the Pavement Marking Plan Sheets comes from various sources including but not limited to, existing pavement marking plans, preliminary field investigations, final survey data, aerial photography, etc.
In recent years, online resources such as ground level imagery have become valuable tools in analyzing existing conditions. Great caution shall be exercised by the engineer when using online data since such data becomes out of date very quickly. Online resources shall not be used to replace a field investigation, but they can be used to supplement a field investigation.
Preliminary Field Investigations
If available, print a half size copy of all previous project pavement markings plans for the current project area. When plans are not available, use the final survey data shown on the new CADD file. It will be necessary to leave landmarks on these plans (driveways, ponds, wells, etc.) to help in locating existing pavement markings while in the field.
Inventory all existing pavement markings and markers and guardrail near and outside the project roadway limits. Take note of lane configurations that will change per the proposed roadway design, such as lane drops and lane reductions. Video may be taken of the entire mainline corridor and -Y-lines, but should not replace the actual field notes. However, in a dangerous work area (heavy traffic with no shoulder, etc.), the video may be used alone. PEFs shall submit to the managing unit all Preliminary Field Investigation data including field notes, photos, and videos if requested by the managing unit.
After the preliminary field investigation, it shall be determined which existing markings, will not be needed or relevant when the project is completed. The Pavement Marking Plan shall show the proposed pavement markings that will replace the existing markings.