This report documents the use of the National Performance Monitoring Research Data Set (NPMRDS) for the computation of freight performance measures on Interstate highways in Washington state. The report documents the data availability and specific data quality issues identified with NPMRDS. It then describes a recommended initial set of quality assurance tests that are needed before WSDOT begins producing freight performance measures.

The report also documents the initial set of performance measures that can be produced with the NPMRDS and the specific steps required to do so. A subset of those metrics was tested using NPMRDS data, including delay and frequency of congestion, to illustrate how WSDOT could use the freight performance measures. Finally, recommendations and the next steps that WSDOT needs to take are discussed.

This report describes the outcome of the initial exploration of the National Performance Research Monitoring Data Set (NPMRDS), supplied by the Federal Highway Administration (FHWA) to state transportation agencies and metropolitan planning organizations for use in computing roadway performance measures.

The NPMRDS provides roadway performance data for the national highway system (NHS). The intent of the NPMRDS was to provide a travel time estimate for every 5-minute time interval (epoch) of the year for all roadway segments in the NHS. The NPMRDS data are derived from instantaneous vehicle probe speed data supplied by a variety of GPS devices carried by both trucks and cars. The data are supplied on a geographic information system (GIS) roadway network, which divides the NHS into directional road segments based on the Traffic Message Channel (TMC) standard.

The report describes the availability, attributes, quality, and limitations of the NPMRDS data on the Interstates in the state of Washington.

Based on the review of the NPMRDS data, this report recommends a set of performance metrics for WSDOT’s use that describe the travel conditions that trucks moving freight within the state experience. It describes specific steps for computing those measures. And it uses a subset of those measures produced with the NPMRDS to illustrate how WSDOT can use those measures in its reporting and decision-making procedures.