Wisconsin Guide Sign Program
In 2008, the Wisconsin Department of Transportation (WisDOT) awarded a contract to 3M Roadway Maintenance Services to upgrade overhead and shoulder-mounted guide signs along U.S. Highway 12 in Madison, Wisconsin. The project includes contract requirements for providing two unique deliverables to WisDOT: (1) furnish and install new high performance, highly reflective guide signs, and (2) provide a project tracking and sign inventory database of the new signs that is compatible with the Department's existing statewide sign inventory system.
On January 22, 2008, the FHWA requirements for maintaining minimum levels of sign retroreflectivity became effective, creating additional incentive for WisDOT to initiate a formal program to begin upgrading their aging guide sign infrastructure. In addition to the actual replacement of non-compliant signs, the "minimums" also require a systematic process of maintaining the signs over time to ensure minimum levels of retroreflectivity are met. WisDOT is currently using an existing inventory system to manage and track the age and sheeting type of their signs, which is an FHWA-approved method to meet the "minimum retroreflectivity" requirement.
WisDOT is considered a leader of utilizing a statewide sign inventory system to manage their traffic signs. One of the challenges for WisDOT is updating their existing sign inventory system once sign improvement projects are completed. The 3M team is solving this problem for WisDOT by providing guide sign installation services that include the use of 3M's web-based data management system. This system tracks the progress of the project on a daily basis, visible to Department personnel at any time, in addition to organizing and tracking the guide sign attribute information that is uploaded into the Department's statewide sign inventory database at the end of the project.
In addition to developing a comprehensive plan to comply with FHWA minimum requirements for guide signs, WisDOT is evaluating the use of high performance retroreflective sheeting on guide signs as a method to turn off guide sign lighting in most situations to create significant energy and maintenance savings. WisDOT is considering a similar performance-based guide sign program in the Milwaukee area that would include upgrade of guide signs and turning off guide sign lighting. WisDOT provided leadership to organize a nationwide study identifying guide sign lighting policies and what other states are doing to address this issue. Thirty states responded to the survey with most states indicating that they are considering some form of a guide sign lighting deactivation program except in certain situations such as locations with frequent fog problems or where road segment geometrics may require lighting to supplement vehicle headlights.
To complete the WisDOT project, 3M is providing guide signs manufactured with high performance 3M™ Diamond Grade™ DG³ Reflective Sheeting incorporating "full cube" technology for optimal performance. This high performance sheeting includes optical elements that are 100 percent efficient, returning almost 60% of available light to the driver's eye - nearly double that of traditional prismatic sheeting material.
Another unique aspect of the WisDOT contract requires the prime contractor to provide a comprehensive 15-year warranty on both labor and materials for finished and installed guide signs to meet minimum levels of retroreflection. As the prime contract holder, 3M maintained complete control of the entire manufacturing, fabrication, and installation process and therefore has put in place the quality checks necessary to take on the added risk to provide this warranty to WisDOT. This warranty guarantees high performance of the guide signs for the entire 15-year warranty period with a virtual "hands-off" situation for WisDOT should any problems develop.