Traffic Data Request Guide for Highway Pavement and Geometric Design (5-1801-01-P1)

The purpose of this guide is to aid the Texas Department of Transportation (TxDOT) in developing the level of traffic data needed to support both highway pavement and geometric design and analysis of traffic for district, state, and federal requirements. This guide will provide you, the highway pavement or geometric designer and district personnel, with a better understanding of the considerations that need to be taken when submitting a request for traffic data. Better traffic data can save millions of taxpayer dollars. Each project has to be evaluated seperately. Your requests for pavement design traffic data should be submitted through the district director of Transportation Planning and Development to the Traffic Analysis Section of the Transportation Planning & Programming (TPP) Division of TxDOT. The collection, analysis, and forcasting of site-specific traffic data are time-consuming processes that are scheduled and thus should be requested in the early stages of project development. This process is especially true if site-specific weigh-in-motion (WIM) data are needed because a smooth, good pavement surface is required for data collection, and the traffic should be sampled during the heavy traffic load period. A fundamental finding of TxDOT Project 0-1801, "Evaluate and Develop an Improved System for Collecting and Reporting Traffic Loads to Better Meet the Needs of Bridge and Pavement Designers," was that not only did the TxDOT districts have a poor understnding of how to request the traffic informtaion needed to support a pavement design, but TPP did not have a process for ensuring that the traffic information being provided was sufficient to meet the pavement design needs. This guide promotes better communication and coordination between the highway pavement and geometric designers and the traffic analysis.