Traffic forecasting

Traffic forecasting is an important component of planning, design and operations for the Wisconsin Department of Transportation (WisDOT). It transforms a wide array of traffic, demographic and economic data into information essential to engineers, intercity and urban planners, project programmers and policy makers.

A traffic forecast is a data element identifying future roadway traffic volumes. The project improvement type and the government authority that oversees the roadway help determine if a forecast is required and the type of forecast (project-level or planning-level) necessary. Chapter 9 of the Transportation Planning Manual (TPM) contains the WisDOT policies and procedures for traffic forecasting and Section 1.4 defines the forecast requirement and type by project type. Additionally, see Facilities Development Manual (FDM) 11-5-2 for traffic forecasting policies.

The following section contains links to resources for requesting and completing forecasts. Planning-level forecasts, geometric design values, and vehicle classification data is provided for use in planning and design of state highways.

Traffic forecasting resources

Project-level forecasts

Project-level forecasts are detailed analyses that may include a mainline and/or turning movement forecast. Request a project-level forecast using form DT1601 - Traffic Forecast Request. If you need a forecast reviewed that was prepared by a consultant or other entity, complete the DT1594 - Forecast Review Request form.

Planning-level forecasts

Planning-level forecasts are generated for projects on the State Highway System (including Connecting Highways) from previously completed project-level forecasts or through an automated forecasting system called the Traffic Analysis Forecasting Information System (TAFIS). For information about TAFIS, refer to Section 30 of the TPM. Contact your WisDOT Region forecast liaison if your project requires a planning-level forecast.

Geometric design values

Geometric design values are calculated for roadway design using data from continuous traffic count sites. Data is available for specific locations and for statewide averages. Refer to Sections 40.1 and 40.3 of the TPM for more information about geometric design values.

Vehicle classification data

Vehicle classification data is used to describe the mix of passenger cars and trucks. Data is available for specific locations and for statewide averages. Data is collected based on the number of axles a vehicle has or the vehicle length.

DTIM Planning Forecast Application

The DTIM Planning Forecast Application is an interactive mapping application that was developed to display the planning-level forecasts, geometric design values at continuous traffic count sites, and vehicle classification data.

Email with any questions on these resources.