Data centers go underground

Computerworld - As Hurricane Ike bore down on Houston one Friday last September, the Continental Airlines' flight operations center, located on the 14th floor of a glass-sided downtown high rise, suddenly went dark. For the airline's pilots and flight crews, however, business proceeded as usual.

Here's why: At that same moment, 42 miles north of the city and some 60 feet underground -- in a hardened Cold-War era bunker built by a paranoid millionaire oilman to survive a nuclear holocaust -- Continental's backup data center took over. Throughout the ordeal -- from Friday morning, as the storm approached, through Saturday, when winds above the Westland Bunker in Montgomery, Texas, gusted to 125 miles per hour, until Sunday evening, when operations resumed in Houston -- the airline managed an 89% on time rating for its global flight schedule.

Locating a backup data center in an underground bunker may seem like overkill, even in a hurricane zone. But the facility met all of the airline's requirements -- including cost, says John Stelly, managing director of technology at Continental. The bunker, run by real estate partnership Montgomery Westland, has been converted into 33,000 square feet of rack-ready data center space complete with air conditioning, redundant network and power sources, uninterruptible power supply systems and backup generators.

Continental leases 2,000 sq. feet underground and another 12,500 sq. feet of office space above ground, in a hardened building complete with 3-inch-thick bulletproof windows. The airline can house its entire operations staff of up to 125 people at the backup site.

After Hurricane Katrina, Continental began looking for a fallback data center for use during hurricanes. Westland "was far enough away to be out of harm's way but close enough for folks to drive to," Stelly says. The blast-resistant facility is admittedly a bit much for even Continental's backup needs, but the four-feet-thick walls and high security entrance are nice extras, Stelly says.

Also, connectivity options at the Westland facility were a plus. The network and power feeds for the bunker were sourced from areas well away from Houston, while pricing was competitive with above-ground co-location facilities.

Rise of the underground

With a renewed focus on data center outsourcing and space in high availability facilities in short supply, investors such as Montgomery Westland have snapped up and renovated abandoned mines and military bunkers in the hopes of cashing in.

[See related stories: Underground data center image gallery / Comparison chart: Underground data centers]

Since 2007, for example, Cavern Technologies has operated a data center 125 feet below ground in an abandoned limestone mine. The mined out area underground, which covers 3 million sq. feet, is 15 minutes outside of Kansas City, Mo. Unlike other mines, the Cavern facility was created with the idea of reuse in mind, so floor space isn't irregularly shaped like other underground facilities can be, says president John Clune. The area's relatively low electricity costs, at 3.5 cents per kilowatt-hour, help to make operating costs lower than those in other parts of the country, he adds.