Up-to-date information on how travel demand is affected by transportation system changes is essential to support planning and evaluation of alternative facilities and services, and for planning operational and policy changes to urban transportation systems. Projections and data on the number, mode use, and other characteristics of travelers are fundamental inputs to many transportation planning activities. This updated handbook will provide a useful reference for those involved in planning and improving transportation systems. Travel demand and related impacts are expressed using such measures as numbers of riders and vehicles using transportation facilities and services, before-and-after market shares and percentage changes, and feasibility indicators of scale.

The Second Edition of the handbook "Traveler Response to Transportation System Changes" was published by USDOT in July 1981, and it has been a valuable tool for transportation professionals, providing documentation of results from different types of transportation actions. However, in the intervening 20-plus years there have been extraordinary changes and advancements in the field. The handbook is being expanded and updated under TCRP Project B-12 and B-12A, and the product will be considered the Third Edition.

The Third Edition of the Handbook will cover 18 topic areas, including essentially all of the nine topic areas in the 1981 edition, modified slightly in scope, plus nine new topic areas. The Traveler Response to Transportation System Changes Handbook provides comprehensive, interpretive documentation of how travel demand and the usage of transportation facilities and services are affected by various types of transportation system changes. It will be of interest to transit and transportation planning practitioners; educators; and researchers across a broad spectrum of transit operating agencies, MPOs, local, state and federal government agencies, and educational institutions.

Status: The Interim Handbook, published as TCRP Web Document 12 in March 2000, makes available the seven topic areas that were completed under TCRP Project B-12: Ch. 2, HOV Facilities, Ch. 5, Vanpools and Buspools, Ch. 6, Demand Responsive/ADA, Ch. 9, Transit Scheduling and Frequency, Ch. 10, Bus Routing and Coverage, Ch. 12, Transit Pricing and Fares, and Ch. 13, Parking Pricing and Fees. Those seven chapters have since been updated and published under the TCRP Report 95 series.

Additional topics were analyzed and completed under TCRP Project B-12A, which began November 5, 1999. In addition, each Interim Handbook chapter is being published in a separate TCRP Report 95 volume with updates to certain information. See Project B-12A for additional and replacement chapter/volumes as they are published (click "Next Project" below).

TCRP Web Document 12 is available in PDF. The TCRP Report 95 series is available in PDF and print.