NASA will reduce its facilities and infrastructure by 15 percent over the next 40 years while balancing its existing work force needs against changing demands when the agency retires its space shuttle fleet and outsources operations in low Earth orbit to the private sector, a senior NASA official said.

With more than 80 percent of NASA facilities at least 40 years old, the agency is looking for ways to streamline excess capacity while retaining strategic capabilities for future use, said Woodrow Whitlow, associate administrator of NASA’s new Mission Support Directorate at agency headquarters in Washington.

“We have a plan where we’re going to drive the average age of our buildings, at least 63 percent of them … [to] under 40 years of age, and we’ll do that over a 40-year period,” Whitlow said March 30 during the Goddard Memorial Symposium, a three-day conference held March 29-31 in Greenbelt, Md.

Whitlow said his directorate will focus on preserving existing structures and capabilities while aggressively modernizing its infrastructure to be cheaper and more efficient to operate. He said an example is the new Propellants North Administration and Maintenance facility at NASA’s Kennedy Space Center, Fla., which produces more energy than it consumes.

NASA currently maintains more than 4,800 buildings and structures with a combined replacement value of over $27 billion. Whitlow said he plans to work with NASA field centers and other support facilities in the coming months to evaluate agency demand for the products they supply. In the meantime, as the agency transitions from its space shuttle and follow-on Constellation programs to new commercial space and technology development initiatives, his directorate will be tasked with recalibrating NASA’s mission support needs.

“We have these transition issues of how do we get the work force we have from where we are now to what we’re going to need to do,” Whitlow said.

In the $18.7 billion spending plan for 2012 that NASA unveiled in February, the agency expects to reassign 90 percent of its space shuttle work force “to follow-on work” by Sept. 30 next year.

“Some of that’s going to require retraining some people, require some rebalancing of work force that we have,” he said.

Whitlow said NASA was already in the process of reducing excess infrastructure when he took the helm of the new Mission Support Directorate and the roughly $3.37 billion annual operations and maintenance budget it oversees, including just over $3 billion in cross-agency support and about $350 million in construction and environmental compliance funding. “Over the last five years we’ve taken down 735 facilities and taken over $1.3 billion worth of infrastructure off the books,” he said. “We want to get similar capabilities, but smaller, so over this 40-year period we’ll reduce our footprint by 15 percent.”

Whitlow described NASA’s $3 billion annual cross-agency support budget as “a nice target for a reduction,” a reference to a spending plan approved by the U.S. House of Representatives in February that would trim that account by nearly $300 million this year relative to the 2010 appropriation. The reduction was part of a broader spending package that was rejected on the floor of the U.S. Senate in March. But lawmakers did approve a $63 million reduction to NASA’s cross-agency support line as part of the latest in a series of stopgap spending measures intended to keep federal agencies operating in the current budget year.