Last week, Kirk Johnson reported in the Times about the I-70 corridor that rises up into the mountains west of Denver — a four-lane rural road which now faces many of the same congestion issues as any urban commute corridor: crushing traffic loads for a few hours a week, with sort of capacity enhancement proving to be frightfully expensive. Much of this results from settlement patterns that resemble nothing so much as the old “pearls on a string” commuter rail towns: dense, pedestrian-friendly nodes clustered along a single corridor, although unfortunately a freeway rather than a railroad in this case.

Appropriately, many of the solutions that have been implemented to date are similarly incongruous urban fixtures dropped into stunning mountain wilderness: HOV lanes along Hwy 82 into Aspen, all-day transit equipped with advanced ITS, and even several proposals for rail service. (The principal difficulty: I-70 follows an available rail alignment west of Vail, but the section through Summit County and east to Denver is too steep for conventional rail service — and would likely require an additional tunnel at the continental divide.) Now, the ultimate in urban congestion solutions is on the table:

[Colorado State Senator Chris] Romer’s suggestion — congestion pricing using financial incentives to encourage people to drive or not drive at peak times on I-70 — drew 500 e-mail messages in the first 24 hours after it was reported in The Rocky Mountain News. About 70 percent opposed the plan, he said, and many of those called him exuberantly bad names… “But we’re not going to solve this problem by being cautious, which is what government does best,” he said, explaining that reliance on gasoline taxes and highway construction will not work… “We have to get creative,” Mr. Romer said. “And if we fail, we adjust and we try again.”

The long shadow haunting the Sunbelt’s growth (and any future long-term infrastructure investments), is the potentially disastrous changes in precipitation that will accompany global warming. Some climate models predict that snowpack in much of the Rockies could become un-skiable during my lifetime. (I’ll be 70 years old in 2050.) The result would destabilize existing ecosystems in an area where human settlements closely abut wilderness; increasingly catastrophic floods, mudslides, and wildfires would further threaten . Economically, the resulting economic losses could be monumental, similar to a hurricane wiping away another beach city.

Meanwhile, cities across the nation’s southern tier, like Atlanta, Las Vegas, and Raleigh are all already sinking deeper straws to suck up even the pond scum from their drought-ravaged reservoirs. Georgia has resorted to desperate new lows, some of which actually date from the 18th century — not just praying for rain (perhaps more of a strong-arm tactic to embarrass Florida to reduce its claim to downriver flow), but recently seeking to move its Tennessee border. Yet these areas continue to grow; as with electricity, the expectation is just that water will be provided regardless of cost or future prospects — and reporting on the crisis continues to focus on such short-term thinking. Sure, conservation pricing has resulted in higher water bills for many (Mayor Franklin in Atlanta pays about $100 a month for water) — but how high would water bills have to go in order to dissuade new arrivals, or to convince non-water-intensive industries (e.g., not manufacturers) to begin looking elsewhere? My guess is that prices would have to go very high indeed.