I-355 South Extension Opens: Cause For Celebration Or Mourning?

The South Extension of I-355 opens tomorrow after today's festivities. The South Extension runs about 13 miles from I-55 to I-80 in New Lenox, mostly in Will County. While much of the corridor is still rural in character, subdivisions are replacing cornfields and there is much commercial development along the corridor, including at least two developments of around two million square feet apiece. In short, the Chicago metropolitan region is sprawling some more.

From all accounts, Will County residents are generally in favor of the South Extension. A Sierra Club lawsuit stopped construction in the mid-1990s, but no environmental group filed such a challenge this time. (Timeline here.)

Should we view the South Extension as a welcome addition to the region's transportation system or is it an investment in auto transportation that is a reckless gamble when oil prices are continuing their climb to $100/barrel and beyond? Is the increase in convenience for Will County residents outweighed by the environmental costs associated with ramming an expressway through a rural area and the sprawl-type development that will inevitably result? Why did the Sierra Club (and other such groups) take a pass on challenging the South Extension this time around?

Final question: The South Extension cost about $750 million. Is the region better off with this investment or would the money have been better used on fixing the region's public transportation system?