But tucked into the 55-page report on the possibility of trading taxes by the gallon for taxes by the mile (see "Back-Seat Big Brother," May 25, 2005) is one passage that-if you like highway travel and the American Way of Life-is more than a little frightening.

"Some petroleum industry experts predict that before 2010 the world production of conventional oil will crest and enter a permanent decline," the report states under the heading "Peak Oil."

Peak oil is the theory that, due to a finite supply of petroleum, the world's production must soon fall.

With rising gas prices and China's growing petroleum demand, peak oil has become an increasingly hot topic. Books and websites declare the end of the oil era, while Big Oil says the peak could be at least 100 years away.

The ODOT report released this month takes a more pessimistic tone. "There's no controversy over the idea of a peak," says the report's author, James Whitty. "The question is: When will it happen?"

After the peak, the report says, increasingly fuel-efficient vehicles will render the 24-cent-per gallon gas tax useless to fund road repairs. (Read the report at www.oregon.gov/ODOT/HWY/OIPP/ruftf_reports.shtml.)

What the report doesn't address is the theory's bleaker side: Competition for dwindling oil reserves could lead to nuclear war, economic catastrophe or-if you're a real pessimist-the end of civilization. By then, potholes might be the last thing on people's minds.