Why are there discrepancies between the Southeastern Wisconsin Regional Planning Commission (SEWRPC) s traffic projections and WisDOT s?
First, SEWRPC s model uses average weekday traffic (AWT) volumes; WisDOT uses average daily traffic (ADT) volumes. The differences can be significant; often in suburban areas, AWT is higher than ADT. Second, SEWRPC s future year for projections is 2020; WisDOT s is 2025. Third, SEWRPC modeled demand based on several scenarios, including 2- or 4-lane WIS 164/County J configurations, with and without a Power Corridor alternative, and posted speeds along WIS 164/County J at current limits or reduced to 45 mph corridor-wide. When equated to ADT and 2025, SEWRPC 2-lane, existing speed limit projections compare very favorably with WisDOT 2025 projections. Regardless of which are used, trends indicated by SEWRPC s study of off-alignment alternatives are valid. To repeat for emphasis: no segment of WIS 164/County J will be expanded to four lanes until or if traffic volumes exceed 13,000 Average Daily traffic (ADT). Return to top Q: Why can t WisDOT and local governments improve several of the
