Transportation Design Manual January 2021 Transportation Design Manual CONTENTS CHAPTER 1 – INTRODUCTION .............................................................................................................. 5 CHAPTER 2 - REFERENCES .................................................................................................................. 6 CHAPTER 3 – TRAFFIC STUDY GUIDELINES ...................................................................................... 7 3.1 TRAFFIC ANALYSIS ...................................................................................................................... 7 3.2 TRAFFIC IMPACT STUDY ............................................................................................................. 7 3.3 SIGNAL WARRANT ANALYSIS ..................................................................................................... 7 3.4 INTERSECTION CONTROL EVALUATION (ICE) ......................................................................... 8 3.5 GAP STUDY ................................................................................................................................... 8 3.6 INTERSECTION DELAY STUDY ................................................................................................... 8 3.7 TRAVEL TIME AND DELAY STUDY .............................................................................................. 8 3.8 NO-PASSING ZONE STUDY ......................................................................................................... 8 3.9 ADVISORY SPEED STUDY ........................................................................................................... 9 3.10 SPOT SPEED STUDY .................................................................................................................. 9 3.11 TRANSPORTATION SAFETY STUDY ......................................................................................... 9 CHAPTER 4 – COMPLETE STREETS .................................................................................................. 10 4.1 GENERAL ..................................................................................................................................... 10 4.2 IMPLEMENTING COMPLETE STREETS .................................................................................... 10 CHAPTER 5 – ACCESS MANAGEMENT SYSTEM FOR ARTERIAL AND COLLECTOR ROADS ... 11 5.1 GENERAL ACCESS STANDARDS .............................................................................................. 11 5.2 DESIGN AND CONSTRUCTION CRITERIA FOR ACCESS CONNECTIONS TO COUNTY ROADS ................................................................................................................................................ 12 CHAPTER 6 – SIDEWALK DESIGN ...................................................................................................... 27 6.1 GENERAL ..................................................................................................................................... 27 6.2 GEOMETRY .................................................................................................................................. 27 6.3 CURB RAMPS .............................................................................................................................. 27 6.4 DETECTABLE WARNING PADS ................................................................................................. 27 Page 2 of 48 Transportation Design Manual CHAPTER 7 – BIKE FACILITY DESIGN ............................................................................................... 28 7.1 GENERAL ..................................................................................................................................... 28 CHAPTER 8 – TRAIL AND SHARED-USE PATH DESIGN .................................................................. 29 8.1 GENERAL ..................................................................................................................................... 29 8.2 TRAIL INTERSECTION CROSSING ............................................................................................ 29 CHAPTER 9 – ROADWAY DESIGN ...................................................................................................... 30 9.1 GENERAL ..................................................................................................................................... 30 9.2 DESIGN SPEEDS ......................................................................................................................... 30 9.3 CROSS-SLOPE ............................................................................................................................ 30 9.4 LANE WIDTHS .............................................................................................................................. 30 9.5 TURN LANES ............................................................................................................................... 31 9.6 LANE TRANSITIONS .................................................................................................................... 31 9.9 UNDERDRAINS ............................................................................................................................ 31 9.10 RETURN RADII ........................................................................................................................... 32 9.11 ROADSIDE DESIGN ................................................................................................................... 32 9.12 INTERSECTIONS ....................................................................................................................... 32 9.13 ROUNDABOUTS ........................................................................................................................ 33 9.14 DRIVEWAYS AND TURNOUTS ................................................................................................. 33 CHAPTER 10 – PAVEMENT DESIGN ................................................................................................... 34 10.1 GENERAL ................................................................................................................................... 34 10.2 FUNCTIONAL CLASSIFICATION .............................................................................................. 34 10.3 STRUCTURAL COEFFICIENT ................................................................................................... 34 10.4 PAVEMENT STRUCTURE ......................................................................................................... 35 CHAPTER 11 – TRAFFIC CONTROL ................................................................................................... 37 11.1 GENERAL ................................................................................................................................... 37 11.2 DESIGN ...................................................................................................................................... 37 11.3 LANE CLOSURES ...................................................................................................................... 37 11.4 PEDESTRIAN AND BICYCLE FACILITY CLOSURES .............................................................. 37 Page 3 of 48 Transportation Design Manual CHAPTER 12 – TRAFFIC SIGNS .......................................................................................................... 38 12.1 GENERAL ................................................................................................................................... 38 12.2 ROADSIDE MEMORIAL POLICY ............................................................................................... 38 CHAPTER 13 – PAVEMENT MARKINGS ............................................................................................. 40 13.1 GENERAL ................................................................................................................................... 40 13.2 DESIGN ...................................................................................................................................... 40 13.3 SUPPLEMENTAL CRITERIA ..................................................................................................... 40 CHAPTER 14 – TRAFFIC SIGNALS ..................................................................................................... 41 14.1 GENERAL ................................................................................................................................... 41 14.2 SUPPLEMENTAL CRITERIA ..................................................................................................... 41 CHAPTER 15 – TRAFFIC SIGNAL RETIMING ..................................................................................... 42 15.1 GENERAL REQUIREMENTS ..................................................................................................... 42 CHAPTER 16 – TRAFFIC CALMING .................................................................................................... 43 16.1 GENERAL ................................................................................................................................... 43 CHAPTER 17 – ROADWAY STREET LIGHTING ................................................................................. 44 17.1 GENERAL ..................................................................................................................................