The state of Tennessee, which owns the 70,000-square-foot data center near the Cumberland River in Nashville, began a $68 million project this month to build a second data center about 25 miles southeast of Nashville.

The state knows that its 21-year-old data center has reached its end and originally wanted to close it and move its systems to two new data centers. But Mark Bengel, the state's CIO, said budget shortfalls have prompted the state to take an alternative path of building one data center at a time.

Once the new 35,000-square-foot data center is completed, which is expected by the end of the first quarter of 2009, the state will move "the most critical applications" to it, Bengel said. The facility will also serve as a fail-over site, he said. The new data center will cost $44 million, with the balance of the spending to be used to outfit it with infrastructure and IT equipment.

The Nashville data center is unstable because it was built on a landfill. The foundation has been cracking and part of the facility is sinking. The IT staff avoids adding more weight in some sections to help stabilize the building. The data center also has some single points of failure, including one power source, which Bengel said is unacceptable.

But Bengel said the existing facility will hold up until the second data center is built and the migration is complete.

The wild card for the project, and for that matter much of Nashville and areas beyond, is what would happen if the Wolf Creek Dam on the Cumberland River in Jamestown, KY., failed. It is the largest dam east of the Mississippi and the Army Corps identified it last year as one of five dams nationwide most at risk of failing.

Bengel said he has been unable to get the Army Corps "to give us a clear estimate about how big of a risk it is. They just don't know or won't say."

Allison Jarrett, a public affairs specialist with the Army Corps, said the dam remains on the high-risk list, and although the level of risk is difficult to quantify, the potential for failure is minimal. "We really have no concern that the dam is going to fail," she said.

Although the dam has problems, Jarrett said the risk calculation considers the consequences if something should happen. A low risk of failure, coupled with big consequences should it fail, magnifies the potential risk and moves it up the list, she said. The U.S. is spending about $314 million over a number of years to improve the dam.