The J. Edgar Hoover FBI Building in Washington. (Rich Clement/BLOOMBERG)

The J. Edgar Hoover Building, which occupies an entire block at a choice Pennsylvania Ave. intersection in downtown Washington, is “aging” and “deteriorating” and in need of serious repairs, the Government Accountability Office said Tuesday. The FBI, in coordination with the General Services Administration — which oversees most federal buildings — is reviewing a series of proposals to either renovate the building or relocate the agency to a new home — but none of the options come cheap, according to the report.

Much of the problem stems from the agency’s staff growth since the Sept. 11, 2001 terrorist attacks. Back then, 9,700 headquarters staffers worked at seven locations; now, about 17,300 employees and contractors work at 40 separate sites across the country, including 22 in the Washington area.

The FBI headquarters is named for the agency’s former director, J. Edgar Hoover, seen here at the end (left) and beginning (right) of his career. (ABC PHOTOGRAPH)

The GAO report and FBI officials agree there are long-standing security concerns with the agency’s current headquarters and nearby leased locations. The Hoover Building, completed in 1974, is surrounded by four busy D.C. streets — 9th, 10th and E Streets, and Pennsylvania Ave and vehicle barriers and a dry moat protect the building from potential attacks. Still, the Hoover Building, like most downtown D.C. locations, is just a few feet from the road.

Much of the agency’s leased annex space is located in multi-tenant buildings and the FBI maintains little control over common areas, including lobbies or parking garages, GAO said.

So what can the FBI do? It has a few options, according to the report:

1.) Stay in its current location: Keeping the current Hoover Building doesn’t do anything to solve the space or security issues, GAO said, and staying put would require the FBI to continue leasing space. The cost of doing so is likely to climb higher in the coming years.

2.) Renovate the Hoover Building and consolidate leases: Renovations and new leases wouldn’t completely solve the space and security problems, but repairs to the current headquarters would allow for upgrades and make it more energy efficient. It would take up to 14 years to complete renovations, at a cost of at least $1.7 billion, GAO said.

3.) Demolish the Hoover Building and rebuild at the same site: Security concerns would remain, but tearing Hoover down and constructing a new building would solve the space concerns. But agency operations would likely remain dispersed across dozens of locations. Estimates suggest it would take at least nine years to complete the project at a cost of at least $850 million.

4.) Build a new headquarters at a new location: This option would solve space and security concerns and ideally would be located on about 50 acres of land accessible to D.C.-are public transportation systems, GAO said. In 2010, the FBI and GSA estimated the project would take at least seven years and cost at least $1.2 billion — but those costs didn’t include how much it might cost for new furniture and equipment.

If history is any guide, it could take more than a decade until the FBI finds a new home: It took Congress more than 12 years to authorize, plan and construct the Hoover Building in the 1960s and 1970s.

Until the FBI finds new space, the report said the agency should work with GSA to ensure at least minimal renovations are made to the Hoover Building to ensure the safety and functionality of the building. Officials quoted in the report said the plan to do so.

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