NCHRP Report 825, Planning and Preliminary Engineering Applications Guide to the Highway Capacity Manual, will help planners apply the methodologies of the Highway Capacity Manual (HCM) 2016 Major Update to common planning and preliminary engineering analyses (including scenario planning and system performance monitoring). It shows how the HCM can interact with travel demand forecasting, mobile source emission, and simulation models and its application to multimodal analyses and oversaturated conditions. Three case studies (freeway master plan, arterial bus rapid transit analysis, and long-range transportation plan analysis) illustrate the techniques presented in the guide. In addition to providing a cost-effective and reliable approach to analysis, the guide provides a practical introduction to the detailed methodologies of the HCM.

 

NCHRP Synthesis 427: Extent of Highway Capacity Manual Use in Planning, recommended the development of an applications guide to address the use of HCM procedures in planning and preliminary engineering applications such as corridor studies, roadway widening projects, and traffic impact analyses. Survey respondents for that synthesis study thought that an applications guide could increase the accuracy and reliability of planning study results. It would also enhance the value of the resources used in the development of the HCM by allowing its broader use.

 

Under NCHRP Project 07-22, Kittelson & Associates, Inc., analyzed each chapter of the HCM to identify material that could be profitably applied to planning and preliminary engineering analyses. They also conducted focus groups to build upon NCHRP Synthesis 427 regarding the use of the HCM and other tools in planning and preliminary engineering applications. The research team then wrote the guide and refined it through workshops with public agencies.

 

When the NCHRP project began, the intent was to base the guide upon the 2010 HCM. NCHRP Project 03-115 was subsequently funded to provide a major update to the HCM, and this guide is based upon that update, released in 2016.