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Publication Number: FHWA-HRT-09-039
Date: April 2010
Pavement Marking Demonstration Project: State of Alaska and State of Tennessee-Report to Congress
Chapter 1. Introduction
Section 1907 of Public Law 109-59 SAFETEA-LU directs the Secretary of Transportation to:
“…conduct a demonstration project in the State of Alaska, and a demonstration project in the State of Tennessee, to study the safety impacts, environmental impacts, and cost effectiveness of different pavement marking systems and the effect of State bidding and procurement processes on the quality of pavement marking material employed in highway projects. The demonstration projects shall each include an evaluation of the impacts and effectiveness of increasing the width of pavement marking edge lines from 4 inches to 6 inches and an evaluation of advanced acrylic waterborne pavement markings.”(1)
Furthermore, the Secretary is directed to “…submit to Congress a report on the results of the demonstration projects, together with findings and recommendations on methods that will optimize the cost-benefit ratio of the use of Federal funds on pavement marking.”(1)
In response, the FHWA established a research project to address the directives described above. The intent of the research was to provide answers to four questions related to the efficacy and safety of pavement markings. To satisfy the requirements of section 1907 and to provide a definitive report on the “methods that will optimize the cost benefit ratio of the use of Federal funds on pavement marking,” the FHWA divided the legislative directive into the following topics:(1)
The purpose of this report is to describe the work performed to date for the SAFETEA-LU§ 1907 Pavement Marking Demonstration Project. The remainder of this report is divided in five main sections—the first four sections provide descriptions of the four studies, and the last section describes the current findings and anticipated recommendations. Supporting appendices are also provided and referenced as appropriate.
This report describes the work performed as of January 2009. Interim reports on literature reviews, experimental plans, and progress reports are not included herein. All of the work conducted under this research project, which is scheduled to terminate in June 2010, will be documented in a final research report provided to the FHWA.
Transportation is a major sector of the U.S. economy. It moves people and goods, employs millions of workers, generates revenue, and consumes resources and services produced by other sectors of the economy. In 2005, transportation-related goods and services contributed $1.3 trillion to the $12.5 trillion U.S. gross domestic product (10.4 percent).(2) A large amount of transportation occurs on the Nation’s 4 million mile backbone of streets and highways.(2) In general, the safety and quality of these streets and highways are unmatched anywhere else in the world. Many of the highway safety innovations used throughout the world have been developed in the United States.
Pavement markings play an important safety function on U.S. roads. They are widely accepted as being beneficial to drivers because they communicate the intended travel path for short-range operations and the roadway alignment for long-range delineation. To ensure consistent application of pavement markings, their characteristics and warranting criteria are described in the Manual on Uniform Traffic Control Devices (MUTCD), setting national standards on their application.(3)
Despite the national pavement marking standards described in MUTCD, according to a recent AASHTO report, a highway death occurs every 21 minutes as a result of a lane departure. In total, that is over 25,000 fatalities per year or almost 60 percent of the Nation’s highway fatalities.(4) Because these types of crashes are the Nation’s largest safety problem, FHWA promotes a strategic approach to prioritizing and implementing a safety program that includes appropriate countermeasures with roadway departure as one of FHWA’s four focus areas for safety. In addition, AASHTO has developed its SHSP that is designed to reduce these numbers.(5) The first objectives of the FHWA focus areas and AASHTO safety plan are to keep vehicles in their lanes and on the roadway. Installing and maintaining effective pavement markings is one immediate and obvious way to meet these objectives.
As called for in SAFETEA-LU, individual States have developed SHSPs.(1) For instance, for the last 3 years, the Missouri Department of Transportation has focused on lane departure countermeasures. It has implemented various countermeasures, including increasing the pavement marking width on all major highways to 6 inches, which has led to a 25 percent reduction in lane departure fatalities from 2005 to 2007.(4)
The science and effort dedicated to effective pavement marking materials and practices can sometimes be overlooked. This may be a function of pavement marking unit costs, typically presented in cents per foot, which are on the order of $0.10/ft to $0.25/ft for installation of conventional markings. However, when each marking on a highway and each mile of a highway are added up, the annual cost of pavement markings in the United States can be surprising. Several sources of State agency information were combined to develop an estimated annual cost of pavement markings, which is based on data from 18 States making up 45 percent of the State-maintained highway miles in the United States.(6) Extrapolating the average cost per mile for the remaining 32 States produced a total annual estimated pavement marking expenditure of $911 million in 2007. This figure is about 1.5 percent of the estimated total capital and maintenance expenditures on State-maintained facilities in the same year (approximately $62 billion).(7)
In addition to State-maintained facilities, pavement markings are also installed on local roads, toll-authority roads, private roads, and other facilities such as parking lots and airports. Local roads account for about 75 percent (2.93 million mi) of the Nation’s highways and roads, and 1.65 million mi of that are paved.(8,9) While many of these roads are not marked, there is a substantial proportion that are marked. Historically, approximately 50 percent of fatal crashes occur on local (county, township, and city) roadways.
The task of managing pavement markings falls jointly upon Federal, State, and local transportation agencies (private or semiprivate authorities are also involved in some jurisdictions). These agencies serve as stewards of the public and work within available sources of funding to install and maintain pavement markings in an efficient and effective manner.
The key elements of pavement marking performance are visibility and durability. It is important that drivers can see the pavement markings during the day and night, and it is important that the markings provide a sufficient service life. Paint traditionally has been used for pavement markings because of its availability and low cost; however, the durability of paint is generally less than 1 year, depending to a large degree on traffic volumes, environmental conditions, and the need for plowing operations in snowbelt States. Newer pavement marking materials are constantly being developed to increase visibility and durability but at higher initial costs. These newer materials generally require more sophisticated application equipment and techniques, which are not typically cost effective for transportation agencies to own and operate. Therefore, many of the newer materials are installed by contractor forces rather than agency personnel. This leads to various contracting options, such as performance-based and warranty-based specifications.
Maintaining pavement markings is important for adequate operational performance and safety. Accordingly, maintenance personnel in transportation agencies are charged with managing the visibility and durability of pavement markings. The challenge of maintaining visible markings throughout the year is especially difficult in high-traffic locations and on mountain pass highways as well as for States that allow studded tires or have bare pavement snow removal practices. Many States have found it most efficient to apply waterborne paint pavement markings twice a year because of winter maintenance activities. Even with this level of attention, pavement markings on mountain passes or horizontal curves cannot always be maintained in a cost-effective manner at specific levels.
In addition to testing marking visibility and durability, many agencies are experimenting with advances in pavement markings to reduce crashes. Other factors, such as an emphasis on accommodating older drivers, have inspired States to evaluate their pavement marking programs. States are also experimenting with different bidding and procurement processes in an effort to be more efficient with getting quality pavement markings on the road.
The research topics included in the SAFETEA-LU § 1907 Pavement Marking Demonstration Project are timely and appropriate, as they address many of the ongoing issues that Federal, State, and local transportation agencies face. This report has been prepared to address the topics as described in SAFETEA-LU § 1907.
Topics: research, safety, roadside, pavement marking
Keywords: research, safety, Acrylic waterborne paint, Durability, Environmental impacts, Pavement markings, Retroreflectivity, State bidding procedures, Wider edge lines
TRT Terms: research, Safety and security, Safety, Transportation safety