Traffic Manual M 51-02.10 May 2021 Engineering and Regional Operations Traffic Operations Americans with Disabilities Act (ADA) Information: This material can be made available in an alternate format by emailing the Office of Equal Opportunity at [email protected] or by calling toll free, 855-362-4ADA(4232). Persons who are deaf or hard of hearing may make a request by calling the Washington State Relay at 711. Title VI Notice to Public: It is the Washington State Department of Transportation’s (WSDOT) policy to assure that no person shall, on the grounds of race, color, national origin or sex, as provided by Title VI of the Civil Rights Act of 1964, be excluded from participation in, be denied the benefits of, or be otherwise discriminated against under any of its programs and activities. Any person who believes his/her Title VI protection has been violated, may file a complaint with WSDOT’s Office of Equal Opportunity (OEO). For additional information regarding Title VI complaint procedures and/or information regarding our non-discrimination obligations, please contact OEO’s Title VI Coordinator at 360-705-7090. Foreword The Traffic Manual is intended to provide instruction and guidance to department personnel who conduct traffic operations and design activities. This manual identifies state and federal laws and departmental directives, policies and publications that are used to aid in decision making for traffic operations and design issues. It also provides standards to assure uniform application of operational methods and traffic control devices statewide. Updating the Traffic Manual is a continuing process and revisions are issued periodically. Questions, observations and recommendations are invited. The next page is provided to encourage comments. WSDOT Traffic Manual M 51-02.10 Page 3 May 2021 Foreword Page 4 WSDOT Traffic Manual M 51-02.10 May 2021 Contents Chapter 1 General Information 1-1 Overview ...............................................................1-1 1-2 Subject Matter ...........................................................1-1 1-3 WSDOT Traffic Coordination...............................................1-2 1-4 Key Reference Material ...................................................1-7 1-4.1 Other Documents................................................1-8 1-4.2 Other Reference Sources..........................................1-8 1-5 Abbreviations............................................................1-9 Chapter 2 Signs 2-1 General .................................................................2-1 2-2 Sign Design..............................................................2-2 2-2.1 Designing a Sign Message.........................................2-2 2-2.2 Reflective Sign Sheeting Material Requirements......................2-5 2-3 Sign Location, Installation, and Storage ......................................2-7 2-3.1 Sign Location ....................................................2-7 2-3.2 Sign Installation..................................................2-8 2-3.3 Temporary and Permanent Attention Devices ........................2-8 2-3.4 Controlling Vegetation Around Signs................................2-9 2-3.5 Sign Storage.....................................................2-9 2-4 Sign Installation and Maintenance Jurisdiction ...............................2-9 2-5 Traffic Sign Management System (TSMS) ...................................2-11 2-6 State Traffic Laws and Regulations Requiring a Sign for Enforcement ...........2-12 2-7 Regulatory Signs . 2-13 2-7.1 Stop Signs......................................................2-13 2-7.2 Yield Signs . .2-13 2-7.3 Speed Limit Signs ...............................................2-14 2-7.4 U-Turn Prohibition & U-Turns Allowed .............................2-14 2-7.5 Two-Way Left Turn Lane .........................................2-15 2-7.6 Auxiliary Climbing and Passing Lanes ..............................2-15 2-7.7 Keep Right Except to Pass........................................2-16 2-7.8 Vehicles Over 10,000 lbs. Prohibited in Left Lane ...................2-16 2-7.9 Do Not Enter and Wrong Way Signing .............................2-16 WSDOT Traffic Manual M 51-02.10 Page 7 May 2021 Contents 2-7.10 Bicycle and Motorized Foot Scooters Prohibition....................2-16 2-7.11 Roundabout Directional Arrow....................................2-17 2-7.12 No Pedestrian Crossing ..........................................2-17 2-7.13 Pedestrian Prohibition ...........................................2-17 2-7.14 No Turn On Red . 2-17 2-7.15 Shoulder Driving ................................................2-18 2-7.16 Specialized Haul Vehicle Weight Restrictions .......................2-18 2-7.17 Emergency Vehicle Weight Restrictions ............................2-18 2-7.18 Slow Vehicle Turnouts ...........................................2-19 2-7.19 Range Area.....................................................2-19 2-7.20 Unmuffled Compression Brakes...................................2-19 2-7.21 Compression Brake Prohibition ...................................2-20 2-7.22 Traction Device Requirements for Snow Prone Areas ................2-20 2-8 Warning Signs . 2-21 2-8.1 Turn and Curve (Horizontal Alignment) Signs and Advisory Speed Plaques ..................................................2-21 2-8.2 Hairpin Curve ..................................................2-22 2-8.3 Large Arrow ....................................................2-22 2-8.4 Chevron Alignment..............................................2-22 2-8.5 Truck Tipping ...................................................2-23 2-8.6 Stop Ahead/Signal Ahead ........................................2-23 2-8.7 Signal Ahead Sign With Flashing Beacons ..........................2-23 2-8.8 Speed Limit Reduction Ahead.....................................2-24 2-8.9 Low Vertical Clearance...........................................2-24 2-8.10 Merge .........................................................2-27 2-8.11 Added Lane ....................................................2-28 2-8.12 Lane Ends......................................................2-28 2-8.13 Exit Advisory Speed .............................................2-28 2-8.14 Ramp Advisory Speed ...........................................2-28 2-8.15 Intersection Warning ............................................2-29 2-8.16 Roundabout Ahead..............................................2-29 2-8.17 Slippery When Wet .............................................2-29 2-8.18 Tunnel Ahead...................................................2-29 2-8.19 Vehicular Traffic Signs ...........................................2-30 2-8.20 Pedestrian Signs ................................................2-32 2-8.21 Non-Vehicular Traffic Signs .......................................2-33 Page 8 WSDOT Traffic Manual M 51-02.10 May 2021 Contents 2-8.22 Congested Area.................................................2-34 2-8.23 Congestion Ahead . 2-34 2-8.24 Grated Bridge Deck .............................................2-34 2-8.25 Pavement Ruts . .2-34 2-8.26 Rocks..........................................................2-34 2-8.27 Transit Stop Ahead . 2-35 2-8.28 Left Turning Vehicles Ahead ......................................2-36 2-8.29 Lateral Clearance Markers (Object Markers) ........................2-36 2-8.30 Water Over Roadway............................................2-36 2-8.31 Severe Side Winds Ahead . .2-36 2-8.32 Watch for Ice ...................................................2-37 2-8.33 Grooved Pavement..............................................2-37 2-8.34 School Areas ...................................................2-37 2-8.35 School Bus Stops . .2-37 2-8.36 School Bus Turnaround ..........................................2-38 2-8.37 Signing for Reduced School Zone Speed Limit.......................2-38 2-8.38 Flashing Beacons or Flags ........................................2-39 2-8.39 School Crossings................................................2-39 2-8.40 Overhead School Crosswalk Sign..................................2-39 2-9 Guide Signs.............................................................2-40 2-9.1 Types of Guide Signs ............................................2-40 2-9.2 Guide Sign Color ................................................2-41 2-9.3 Guide Signs On Conventional Roads ...............................2-41 2-9.4 Guide Signs On Expressways and Freeways ........................2-41 2-10 Route Signs.............................................................2-42 2-11 Primary Guide Signs . .2-42 2-11.1 General ........................................................2-42 2-11.2 Destination Selection............................................2-43 2-11.3 Control City on Destination Signing ...............................2-43 2-12 Distance Signs ..........................................................2-46 2-12.1 General ........................................................2-46 2-12.2 Determining Mileage Displayed on Distance Signs...................2-46 2-13 Supplemental Guide Signs ................................................2-46 2-13.1 General ........................................................2-46 2-13.2 Destination Selection Factors for Supplemental Guide Signs . .2-47 2-13.3 Destination Selection Priorities ...................................2-47 WSDOT Traffic Manual M 51-02.10 Page 9 May 2021 Contents 2-14 Destination Selection Requirements and Installation Details for Specific Types