WASHINGTON -- The White House Big Dig is finally wrapping up, but the Big Reveal is proving to be a pretty big letdown.

After nearly two years and $86 million worth of noisy and disruptive construction, the West Wing has emerged from its visual seclusion remarkably unchanged. And deep underground, whatever has been built there remains shrouded in mystery.

Plus, if you ask what the next phase is in this massive, four-year project, the official answer is "TBD" – to be determined.

The construction project – officially a long overdue upgrade of White House utilities – began in September 2010 with the excavation of a huge, multistory pit in front of the West Wing, wrapping around to include West Executive Avenue, the street that separates the White House from the Eisenhower Executive Office Building. A tall, green construction fence sprang up that blocked America's most famous office complex from public view.

But now the fence has come down, revealing the familiar whitewashed sandstone facade and the lone Marine guard who stands watch at the entrance to the West Wing lobby.

Bulldozers have covered up the hole. Contractors have repaved the asphalt driveway. National Park Service crews are mostly finished re-grading, re-sodding and replanting. Their goal has been to return the area to its original appearance.

So what, exactly, did all the digging, hammering, welding and concrete-pouring accomplish?

The General Services Administration, which oversaw the work, said it was to replace aging water and steam lines, sewers, storm sewers and electrical wiring conduits. Heating, air conditioning and fire control equipment also are being updated, officials said.

However, what reporters and photographers saw during the construction appeared to go well beyond that: a sprawling, multistory structure whose underground assembly required truckload after truckload of heavy-duty concrete and steel beams.

The GSA maintains this structure is merely "facilitating" the utility work. But neither the agency nor the administration will elaborate on its function. Last year, when the project began, GSA officials denied the construction was for additional office space or another bomb shelter. The existing White House bunker, known as the Presidential Emergency Operations Center, is under the East Wing and dates to the Roosevelt administration.

The GSA went to great lengths to keep the work secret, not only putting up the fence around the excavation site but ordering subcontractors not to talk to anyone and to tape over company info on trucks pulling into the White House gates.

Meantime, for most of those who work in the West Wing, the project has been a huge headache. Sometimes literally.

It's meant shouting to be heard over jackhammers and backhoes, and long walks on arching ramps to circumvent the extensive work zone. The GSA even built a temporary concrete-and-steel platform to elevate TV reporters and their cameras so the White House North Portico could still be seen over the fence. The platform, like the fence, is now gone. And no one's happier than West Wing denizens whose windows were blocked off.

"Now that the sights and sounds of construction workers and their equipment are gone, my outlook on the North Lawn of the White House has, literally, brightened," said deputy press secretary Josh Earnest.

But the respite may be short-lived.

Future phases of the project, whose total price tag tops $376 million, are expected to involve more excavation elsewhere on the North Lawn – the well-groomed park that tourists see from the fence on Pennsylvania Avenue – and possibly inside the East and West wings. GSA officials say wrap-up work is actually continuing on the underground utilities, albeit out of sight.

And they resolutely refuse to identify the next major work area, or to say when that construction will begin.

"The scope of any additional work in the West and East wings has not been determined, so the timing, obviously, hasn't been finalized," said agency spokeswoman Mafara Hobson.

Also on HuffPost:

Loading Slideshow...
  • Wells Blue Bunny Ice Cream, Le Mars, IA

    Josh Haner, a staff photographer for <em>The New York Times</em> who covered the GOP races in Iowa, shared in this article with NY Times blogger James Estrin that Wells Blue Bunny Ice Cream in Le Mars, Iowa, is a must-visit for candidates racing through the state.  <a href="http://www.thedailymeal.com/over-top-burger-toppings-slideshow?utm_source=huffington%2Bpost&utm_medium=partner&utm_campaign=eat%2Bto%2Bbe%2Bpresident" target="_hplink"><strong>Click here to see Outrageous Burger Toppings</strong></a> <em>Photo Credit:</em> © <strong>Wells Blue Bunny Ice Cream</strong>

  • The Machine Shed, Rockford, Ill.

    Famous for its chocolate-covered bacon and Krispy Kreme cheeseburger, The Machine Shed in Rockford, Ill., has been visited by Mitt Romney and Rick Perry this year. <a href="http://www.thedailymeal.com/coolest-people-food-slideshow?utm_source=huffington%2Bpost&utm_medium=partner&utm_campaign=eat%2Bto%2Bbe%2Bpresident" target="_hplink"><strong>Click here to see The Coolest People in Food</strong></a> <em>Photo Credit:</em> © <strong>The Machine Shed</strong>

  • Lizard's Thicket, Columbia, S.C.

    Perry and Santorum both enjoyed some down-home Southern cooking at this South Carolina joint. The restaurant has hosted rallies for half the GOP candidates this year and was Hillary Clinton's restaurant of choice during her 2008 campaign for president in Columbia.  <a href="http://www.thedailymeal.com/what-stars-eat-between-takes-slideshow?utm_source=huffington%2Bpost&utm_medium=partner&utm_campaign=eat%2Bto%2Bbe%2Bpresident" target="_hplink"><strong>Click here to see What the Stars Eat Between Takes</strong></a> <em>Photo Credit:</em> © <strong>Lizard's Thicket</strong>

  • Comma Coffee, Carson City, Nev.

    Comma Coffee is a relatively new kid on the block to political campaign stops, but since they opened their doors in 2000, they have hosted Hillary Clinton, President Barack Obama, Joe Biden, Dennis Kucinich, Ron Paul and even former President Jimmy Carter. <a href="http://www.thedailymeal.com/americas-50-most-powerful-people-food-2012-0?utm_source=huffington%2Bpost&utm_medium=partner&utm_campaign=eat%2Bto%2Bbe%2Bpresident" target="_hplink"><strong>Click here to see America's 50 Most Powerful People in Food</strong></a> <em>Photo Credit:</em> © <strong> Journalist </strong>

  • Wings Plus, Coral Springs, Fla.

    According to The Sun Sentinel, former President George W. Bush put Wings Plus on the political campaign map in Florida by campaigning there for re-election in 2004. This campaign season, Wings Plus has hosted rallies for Herman Cain, Rick Santorum and Newt Gingrich. <a href="http://www.thedailymeal.com/americas-15-best-french-fries-slideshow?utm_source=huffington%2Bpost&utm_medium=partner&utm_campaign=eat%2Bto%2Bbe%2Bpresident" target="_hplink"><strong>Click here to see America's Best French Fries</strong></a> <em>Photo Credit:</em> © <strong>Wings Plus</strong>

  • Pizza Ranch, Hull, IA

    Ames.Patch.com says that there have been more than 35 visits by Republican candidates this year to Pizza Ranch restaurants in Iowa. The sudden popularity is explained by Dennis Goldford, a political science professor at Drake University. "It's a very convenient location where, presumably, the people who go there know what Pizza Ranch is about. It's a good place to find like-minded people who are open to this kind of message." He's referring to the chain's web site language, where they state their vision is "to glorify God by positively impacting the world we live in."  <a href="http://www.thedailymeal.com/america-s-most-outrageous-grilled-cheese-sandwiches-slideshow?utm_source=huffington%2Bpost&utm_medium=partner&utm_campaign=eat%2Bto%2Bbe%2Bpresident" target="_hplink"><strong>Click here to see America's Most Outrageous Grilled Cheese Sandwiches</strong></a> <em>Photo Credit:</em> © <strong>apolitics</strong>

  • Tommy's Country Ham House, Greenville, S.C.

    Tommy's is a de rigueur stop for candidates on the trail in South Carolina. The Greenville restaurant made headlines this year when both Romney and Gingrich's campaigns booked events for the same time on the same day. Although a Ham House showdown was avoided by some creative rescheduling, both candidates cracked jokes at their rescheduled appearances. "Callista and I are thrilled to be here, but I have a question -- where's Mitt?" Gingrich joked. "I thought he was going to stay and maybe we'd have a little debate here this morning. So I'm kind of confused."  <a href="http://www.thedailymeal.com/americas-oldest-restaurants-slideshow?utm_source=huffington%2Bpost&utm_medium=partner&utm_campaign=eat%2Bto%2Bbe%2Bpresident" target="_hplink"><strong>Click here to see America's Oldest Restaurants</strong></a> <em>Photo Credit:</em> © <strong>Tommy's Country Ham House</strong>

  • Charlie Parker's Diner, Springfield, Ill.

    Mitt Romney visited this Springfield, Ill., diner for pancakes and omelettes during a campaign stop in March. While there, Romney told a joke, comparing Charlie's Famous Giant Pancake, to the Puerto Rico primary results: "These pancakes are about as large as my win in Puerto Rico last night, I must admit," Romney said. "The margin is just about as good." <a href="http://www.thedailymeal.com/where-eat-if-you-want-be-president-slideshow?utm_source=huffington%2Bpost&utm_medium=partner&utm_campaign=eat%2Bto%2Bbe%2Bpresident" target="_hplink"><strong>Click here to see More Places to Eat If You Want to Become President</strong></a> <em>Photo Credit:</em> © <strong>Jimmy Wayne</strong>