The Arizona Department of Transportation says it would be prohibitively costly to improve Interstate 17 in mountainous terrain where serious accidents often block traffic for hours and where potential alternative routes are few and far apart.
ABC15 (KNXV-TV) reports that ADOT spokesman Ryan Harding says at a minimum, improving I-17 from Black Canyon City to Sunset Point would cost $125 million.
Harding says the most obvious solution to congestion, both after crashes and during peak-travel days, would be widening the road with additional lanes, but that currently isn't feasible.
For now, Harding says ADOT will continue studying the interstate for possible solutions.
The news comes days after a massive 24-car pileup crash caused an hours-long backup around Black Canyon City on Sunday.
