As the light fades on a Friday night in October, one can peer from the comfort of Simon & Seafort's Saloon & Grill in downtown Anchorage to the freezing, glacier-ridden Tordrillo Mountains across the silty waters of Knik Arm and see the future of Alaska's largest city looming.

Seen from a distance, viewed from inside the cocoon of comfort that embodies the good life of Alaskans today, it is all very beautiful, a primordial world where snow, cold and dark still rule. Now imagine the scene transposed on the living rooms of Anchorage.

The city's mayor this week painted an apocalyptic vision for a community quickly running out of energy supplies to heat and light homes. It was bleak and a little scary. But even scarier is that after talking to dozens of people familiar with the natural gas pipeline system feeding the city and the region's main electrical powerplants, one can easily get the idea that Mayor Dan Sullivan might actually have understated the danger.

A big, winter earthquake could easily make Anchorage the first major city in America ever to go cold and dark in the style of the fabled nuclear winter, but it might not even need that. Disaster for Anchorage could come simply in gusts of Arctic air sent south from somewhere up near Point Hope or Nome. Residents likely wouldn't even notice the danger at first. What's a little subzero weather in Alaska, after all?

In the worst-case scenario, it's a disaster: An overtaxed supply of Cook Inlet gas declines to the point where residential furnaces start sputtering out, and the local electrical utilities - which are almost wholly dependent on natural gas for the generation of electricity - stop producing power. Some in Anchorage - maybe many - could then find themselves forced to live in the cold and dark the way the state's aboriginal inhabitants did.

Do you have enough seal oil on hand to fuel your winter lamps? Have you built a sod house in the yard that can be easily heated with a few sticks of wood?

Most readers will here, of course, think the author is joking. This is the 21st Century in the United States of America, and Anchorage is the largest city in the energy-richest state in the union. How the hell could Anchorage end up going cold and dark?

Pretty easily, really. The same way any place dependent on one, nonrenewable resource for its survival could go under. If you have doubts about the reality of the risk, consider this: Parts of Anchorage were on the verge of going cold and dark last winter.

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Depending on whom you talk to, you get various versions of how close the city was to disaster. Some say days; others say hours. Whichever was the case, it is clear the community was on the edge of a critical natural gas shortage just as a lengthy January cold snap finally broke and the threat of a system failure began to ease. The big problem last year, everyone agrees, began with the malfunction of one of three compressors that drive gas through lines feeding north from the Cook Inlet basin to Anchorage and the Susitna Valley.

When that compressor went down, pressure in the pipelines started to fall. Tony Izzo, the former head of Anchorage's Enstar gas, and now an energy consultant, contends the city was within two hours of a crisis. Once pressure starts falling, he said, it can drop very fast "and you can't get it back. There's just so much suction on it from (Anchorage) furnaces and water heaters in cold weather.''
Low pressure could force Enstar to shut one or both of the 85-mile-long pipelines that snake across the Kenai Peninsula and under Turnagain Arm to feed most of the city. There is a third pipeline that serves Chugach Electric's Beluga power plant and continues on into the valley, but the bulk of Anchorage's gas moves on the Kenai lines.

And in the winter, when gas demand is at its peak, the city needs both of them moving all the gas they can. Even in the best of times now, Anchorage is in a precarious position, as is most of Southcentral Alaska. The region has grown to include hundreds of thousands of homes sucking on the gas from the Cook Inlet basin.