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3BACKGROUND Most of the 50 states and many local governments have developed their own designs, detailed layout schemes (typi- cal drawings), and associated practices for pavement mark- ings. These designs, layout details, and practices are usually more specific than the requirements of the national Manual on Uniform Traffic Control Devices (MUTCD) (2003). The MUTCD provides general guidance and/or minimum or max- imum dimensions for certain markings, spacing of markings, combinations of markings, and patterns. Among the more detailed designs, layout details, and associated practices that are found in many of the state and local documents are: â¢ Methods of delineating turn lane channelization, â¢ Patterns and spacing of lane-use turn arrows and ONLY word markings, â¢ Patterns and spacing of crosswalk markings and stop lines, â¢ Patterns and spacing of turn arrows in two-way left-turn lanes, â¢ Patterns and dimensions of chevrons and diagonal lines, â¢ Methods of delineating climbing and passing lanes, and â¢ Methods of delineating entrance ramp and exit ramp gores. The purpose of this synthesis was to identify variations in pavement marking designs, practices, and policies of each state department of transportation (DOT) and agencies in the District of Columbia, Puerto Rico, and several large cities and counties. From the information contained in this synthesis, common and differing practices and ranges of typical place- ment dimensions can be identified. This compilation and synthesis of information (which has been unavailable to date) will be highly valuable to FHWA and to the National Com- mittee on Uniform Traffic Control Devices as these organi- zations consider the need for revisions to Part 3 of the MUTCD to add more specificity to the national standards for pavement markings and, where appropriate, to codify the most com- mon policies, practices, and applications of pavement mark- ings. In addition, state and local government agencies can use this information to determine the most common policies and practices in each area of interest as they develop or revise their pavement marking design standards. Many state DOTs, the District of Columbia, and Puerto Rico provide information on pavement markings, and sup- plements to the national and state MUTCDs on their web- sites. These websites were accessed and the pertinent pave- ment marking information for the various areas of interest to this synthesis was obtained and inventoried. The information that was important, but was not provided, was then requested from all 50 states. These requests resulted in additional infor- mation being obtained, either by means of hard-copy docu- ments or through the identification of website addresses that had not previously been visited. Information was also sought from a number of large cities and counties to obtain a sense of the policies and prac- tices that are specific to urban situations. Information was obtained and used in this synthesis from four local govern- mental agencies: â¢ City of Charlotte, North Carolina â¢ City of Los Angeles, California â¢ City of New York, New York â¢ City of Tucson/Pima County, Arizona. Throughout this synthesis, the term âdesign standardsâ is used generically to refer to all of the various types of poli- cies and practices regarding pavement marking layouts that are published by the agencies represented herein. As can be seen in the bibliography, these documents have a wide vari- ety of actual titles, including design standards, traffic man- uals, standard designs, standard plans, design details, typi- cal drawings, standard construction drawings, design manuals, state MUTCDs, and supplement to the MUTCD. However, in this synthesis, for clarity and convenience, all of these various publication titles are generically referred to as design standards. To provide maximum clarity, the terms upstream and downstream are frequently used in this synthesis to de- scribe the pavement marking layout policies and practices. For example, when the phrase âthe end of the lane line sep- arating the turn lane from the through laneâ is used, the reader could interpret this to be the end of the lane line at the stop line or the end of the lane line in the turn lane taper area. However, if the reader keeps in mind that traffic always flows from upstream to downstream, the phrase âthe downstream end of the lane line separating the turn lane from the through laneâ can only be interpreted to be the end at the stop line. Figure 1 illustrates the meanings of the terms âupstreamâ and âdownstreamâ as used in this synthesis. CHAPTER ONE INTRODUCTION
This synthesis is not intended to be used by practitioners as a design guideline when they are developing pavement marking plans in the various states. The information in this synthesis is essentially a âsnapshotâ of current state and local government policies and practices in effect in late 2004 and early 2005. These policies and practices are subject to change, with many agencies indicating that they were in the process of revising their design standards at the time the information in this synthesis was requested. However, prac- titioners can visit the websites listed in the bibliography to obtain the latest design standards for the various agencies that maintain these websites. This report addresses only the information that was found in the various policies and practices regarding pavement marking layouts that are published by the agencies repre- sented in this synthesis. Existing pavement markings and the actual implementation of new pavement markings within a particular state might vary from the stateâs published policies and practices, particularly in small- to medium-sized towns and cities and in the various districts throughout the state. No attempt has been made to discover or document any varia- tions from the published policies and practices within the geographical areas of the agencies represented. In addition, this synthesis does not specifically address the safety aspects or the cost-effectiveness of the various pave- ment marking layout policies and practices of the agencies. It also does not provide any value judgments regarding whether certain policies and practices are superior or inferior when compared with the policies and practices of other agencies. ORGANIZATION In the following four chapters, information regarding the pavement marking policies and practices of most of the 50 states, the District of Columbia, Puerto Rico, and four local government agencies are presented. In each case, the agencies are identified using the postal service two-letter abbreviations for the 50 states (as identified in the Glossary in this report), with DC used for the District of Columbia, PR for Puerto Rico; CLT for Charlotte, North Carolina; LAN for Los Ange- les, California; NYC for New York City, New York; and TUC for Tucson/Pima County, Arizona. 4 In Chapters two, three, and four, the provisions found in the 2003 MUTCD regarding each area of interest are presented first, followed by the policies and practices of each of the 54 government agencies that provided information for the syn- thesis. Because there was no area of interest in this synthesis for which all 54 agencies had a policy or practice, the number of agencies for which a policy or practice was found in their design standards is shown after each subheading throughout these chapters. Chapter two details the pavement markings associated with intersections, including lane lines, turn arrows, and ONLY word markings in turn lanes, dual turn lanes, and dropped lanes; dotted lines in turn lane tapers; crosswalks; stop lines; formation of left-turn lanes between the through lanes on two- lane highways; and right-turn channelizing islands. Chapter three reviews the pavement markings associated with sections of streets and highways between intersections, including midblock crosswalks; passing and no-passing zones; two-way left-turn lanes; climbing and passing lanes; lane reductions; and painted medians, paved shoulders, and approaches to obstructions. Chapter four details the pavement markings associated with the paved gores for entrance and exit ramps at interchanges. Chapter five examines miscellaneous arrows and symbols, word markings, and pavement marking treatments that are not specifically addressed in the provisions of the MUTCD. Chapter six presents the conclusions of the synthesis and lists other types of pavement markings that were not included in this synthesis. This chapter also presents suggestions for future research. Appendix A contains the 16 figures from Chapter 3B of the 2003 MUTCD that are referenced throughout this synthesis. Appendix B is a listing of the Standards from Chapter 3B of the 2003 MUTCD that are referenced in this synthesis. Appendix C is a table that was used during this synthesis to inventory the information that was received from the 54 agen- cies that supplied information. The numbers in this table will assist the reader in finding the desired information in each agencyâs design standards. Appendixes D through R present complete descriptions of each agencyâs policy or practice for each area of interest. The appendixes are arranged by area of interest and the agency information is presented in alphabetical order within each area of interest. Agencies for which no policies or practices concerning a particular area of interest could be found are identified at the end of each appendix. FIGURE 1 Illustration of terms upstream and downstream. Upstream end of lane line Downstream end of lane line