The Road Diet Cross Section Conversion: Information Guide Summary Efficiency through technology and collaboration Keith Knapp, Ph.D., P.E. Iowa LTAP (Thanks Project Team Member & FHWA!) Road Diets A Proven Safety Countermeasure 2 1
3 Road Diet Informational Guide: Contents 1. Introduction What is a Road Diet? 2. Why Consider a Road Diet - Benefits? 3. Road Diet Feasibility Determination 4. Designing a Road Diet 5. Determining if a Road Diet is Effective 4 2
Chapter 1: INTRODUCTION What is a Road Diet? and Special Bonus: What a Road Diet is NOT. 5 What is a Road Diet? 6 3
9/2/2015 Photo Source: Virginia DOT 7 What a Road Diet is NOT Typically No Curb-to-Curb Reduction Mostly Within Existing ROW No Lane Width Reduction Required, But can be Done Think About it Like this: Lane Reallocation Lane Rebalancing Conversion 8 4
Chapter 2: WHY CONSIDER A ROAD DIET? Or What are the Benefits of a Road Diet? 9 Benefits: Safety 4-Lane 3-Lane 19-47% overall crash reduction 10 5
Crash Reduction Research Source 2008 NCHRP Report 617 Combined Iowa, Washington, and California Sites Empirical Baysian Analysis Total Crash Reductions IA: 47% WA & CA: 19% All Sites: 29% Suggestion: Match Roadway Environment to those Studies or Use Average 11 12 6
Benefits: Reduced Conflict Points 13 Reduced Conflict Points 14 7
Better Sight Distance 15 Non-Motorized Safety & Accessibility Photo Source: City of Seattle Photo Source: Stacy Meekins 16 8
Chapter 3: Road Diet Feasibility Determination Is a Road Diet an Appropriate Alternative for the Corridor? 17 Determining Road Diet Feasibility: Identify the Objective(s) One or More of the Following: Improve safety Reduce high-end speeders/differential Reduce queues caused with left-turners Improve pedestrian environment Improve bicyclist accessibility Enhance transit stops Is a Road Diet Alternative something to Consider Further? 18 9
Determining Road Diet Feasibility: Evaluate/Compare Factors & Considerations Chapter 3 of the Guide Safety Factors Context Sensitive Solutions & Complete Streets (CSS/CS) Considerations Operational Factors Bicycle, Pedestrian, Transit, & Freight Considerations Others Appendix B: Example Feasibility Determination Factors, Characteristics, and Sample Evaluative Questions 19 Determining Road Diet Feasibility: Safety Factors and CSS/CS Considerations Safety Factors Crash locations, types, and patterns Safety concerns of all road users Can the crashes occurring be reduced with the conversion? CSS/CS Considerations Roadway function/environment (context) Policy/plan/guide exist? What is the current, expected, and desired roadway function? 20 10
Determining Road Diet Feasibility: CSS/CS Considerations (continued) The street network should be planned, designed, maintained, and operated in a way that accommodates all road users and those who use the surrounding environment. 21 Determining Road Diet Feasibility: Operational Factors Does the current roadway primarily operate as a defacto three-lane roadway? Case-by-case intersection/arterial analysis Photo Credit: Tom Welch 22 11
Determining Road Diet Feasibility: Operational Factors (continued) Average daily traffic (ADT) and peak hour volumes Access point location, design, and use Speed variability, high end speeders, & overall Delays, queuing, diversion, and level of service Frequent stop or slowmoving vehicles Photo Credit: Tom Welch 23 Determining Road Diet Feasibility: Average Daily Traffic Maximum Examples 24 12
Determining Road Diet Feasibility: Seattle Example 25 Determining Road Diet Feasibility: Bicyclist, Pedestrian, Transit & Freight Considerations Number, location, type, and interrelationship Photo Credit: Stacy Meekins Pedestrians Bicyclists Transit/Transit stops Freight/Trucks/Deliveries Roadway in network? Typical successful case study characteristics: improved walkability, increased pedestrian/bicycle use, and terms like more comfortable used 26 13
Determining Road Diet Feasibility: Other Factors Right-of-Way availability & cost Parallel roadways diversion issues Parallel parking At-grade railroad crossings Possibly public outreach, public relations, and political considerations 27 Road Diet Application: Appendix B 28 14
Road Diet Application Material Road Diet Informational Guide http://safety.fhwa.dot.gov/road_diets/info_guide/ Road Diet Case Studies http://safety.fhwa.dot.gov/road_diets/case_studies/ Road Diet Desk Reference http://safety.fhwa.dot.gov/road_diets/desk_ref/ 29 Conclusions Conversions are feasible over a wide range of corridor characteristics Consideration/evaluation of this alternative is case-by-case for all roadway users Are the expected operations/impacts of the conversion acceptable? Some Implementation Guidance Exists Already and Some to Come What would be most Helpful? 30 15
Questions? http://safety.fhwa.dot.gov/road_diets 31 16