How Wisconsin Highway Opponents Cried 'Peak Car' (and Won)

After years of consistently going up, driving mileage in the United States began to plateau around 2005, and it remains shy of historical per-capita highs—a new normal casually called “peak car.” Still many official traffic forecasts remain tainted by the old belief that car use is always on the rise. The result is that highway expansion projects seem necessary to meet driving demands, and taxpayer money goes to building new lanes instead of maintaining existing ones.

Flawed traffic models aren’t going away anytime soon, but their influence suffered an overdue blow in federal court last weekend, in a case involving the $146 million expansion of State Highway 23 in Wisconsin. Judge Lynn Adelman of the Eastern District Court ruled that officials failed to justify their future driving estimates in the face of peak car trends. As a result, the Wisconsin DOT might not have properly considered alternatives that didn’t involve doubling the lanes from two to four.