

Crews inspect a sinkhole Tuesday morning that prompted the closure of the George Washington Parkway’s southbound lanes. (U.S. Park Police)

(Related: Commuters react to sinkhole that caused major delays on GW Parkway)

Updated at 9:16 a.m.

After 12 hours of crews working to fix a pothole that shut down the southbound lanes of the George Washington Memorial Parkway, federal highway officials said they ‘ll now try to figure out what caused the problem.

The roadway’s southbound lanes between Route 123 and Spout Run Parkway were closed all day Tuesday after a sinkhole was discovered Monday night. Crews arrived on the scene around 9:30 a.m. on Tuesday and finished fixing the roadway around 8:30 p.m. the same day. But a small portion of the roadway was still closed in the early morning hours Wednesday because the asphalt was drying in the wet, damp conditions, according to officials at the Federal Highway Administration.

The entire stretch reopened shortly after 6 a.m. Wednesday. On Tuesday, the closure of the roadway caused traffic delays throughout the morning rush hour.

Federal highway officials said Wednesday that they are not immediately sure what caused the sinkhole but are looking into it.

“They were focused on fixing the problem rather than studying it,” said Doug Hecox, a spokesman for the Federal Highway Administration, which was in charge of helping fix the pothole. He said there could be a variety of reasons for sinkholes, including water accumulating underneath the roadway or “changing geological conditions way, way underground.”

“They’re not easily predictable,” he said. He said the 12-hour fix was “especially fast when you consider all the weird weather.” Typically, it is a bit faster and easier to fix roadway problems with asphalt when it is warm and dry.

Updated at 6:06 a.m.

All of the southbound lanes on the George Washington Memorial Parkway are now open after a sinkhole shut it down Tuesday.

Updated at 4:30 a.m. Wednesday

Some of the southbound lanes of the George Washington Memorial Parkway reopened early Wednesday morning, but some work remains on part of the roadway as crews continue to fix an area where a sinkhole erupted.

A sinkhole had led to the shut down of all southbound lanes at Route 123 all day Tuesday.

In a Twitter message, the U.S. Park Police said that the GW Parkway “is open – one right lane closure SB at Windy Run is in place. All lanes will be open for morning commute.”

Around 4:30 a.m., the police said that crews were finishing up some work on the GW Parkway at Windy Run. Drivers can only get by in that section in the right lane at this time, they said.

Both of the southbound lanes on the parkway are expected to fully reopen soon, although police said they did not have a specific time on the reopening. Late Tuesday night, highway officials had said the roadway’s southbound lanes would fully reopen by 5 a.m.

The Tuesday shutdown of the parkway caused major traffic delays in the morning commute.

Truck just unloaded load of gavel into #GWsinkhole pic.twitter.com/TUQpBmzGsC — Bruce Leshan (@BruceLeshan) December 2, 2014

Updated at 9:30 p.m.

One southbound lane of the George Washington Memorial Parkway was reopened Tuesday night after repair of a large sinkhole which shut down the lanes at Route 123 since Monday night.

However, the U.S. Park Police said that one southbound lane of the parkway remained closed at Windy Run. Sgt. Lelani Woods said it would reopen at 4 a.m. Wednesday.

Updated at 4:01 p.m.

As work continued to repair a large sinkhole on the George Washington Memorial Parkway, Federal Highway Administration spokesman Doug Hecox said he expected the road would be entirely open to traffic by 5 a.m.

Updated at 12:46 p.m.

Work is underway to repair a large sinkhole on the southbound lanes of the George Washington Memorial Parkway at Route 123, and officials now say they expect the roadway to reopen before Wednesday morning’s rush hour.

“The backfilling is underway,” said Doug Hecox, a spokesman for the Federal Highway Administration. “We have equipment ready to begin the paving as soon as the backfilling is finished.” He said the sinkhole is being backfilled with dirt and rock.

“The current estimate,” Hecox said, is that the parkway would reopen “tomorrow before rush hour.” But he cautioned that he did not know exactly when that would be and that officials still needed to coordinate with the U.S. Park Police, the agency that helps oversees the roadway.

The southbound lanes of the GW Parkway in that area have been closed since early Tuesday morning and created a headache for commuters, with some people reporting drives of up to three hours to reach their destinations.

Hecox said federal highway crews that are now at the site have found that the sinkhole is “not as large as it was originally estimated to be.” Officials now say the sinkhole measures 10 feet by 5 feet.

Updated at 11:05 a.m.

Federal Highway officials said it is likely to take crews more than five or six hours to fix a large pothole that closed the southbound lanes of the George Washington Parkway at Route 123 on Tuesday morning.

Fixing a sinkhole of this size typically takes five to six hours — if conditions are dry and warm. But with the cold temperatures and rainy conditions, it is expected to take longer. Officials said that means it is likely that the parkway’s southbound lanes will remain closed through Tuesday evening’s rush hour and could be closed into Wednesday morning’s rush hour, as well.

“With the cold, it is likely all of the work will be done late tonight,” said Doug Hecox, a spokesman at the Federal Highway Administration. He said it will be up to the U.S. Park Police to decide when to reopen the road. Just before 11 a.m., Sgt. Lelani Woods, a spokeswoman for the park police, said in an e-mail: “It is still unknown as to how long the closures will be in effect, however, with weather permitting repair efforts can begin soon.”

One problem in fixing the sinkhole, highway officials said, is that it depends on how the asphalt reacts with the wet weather.

“Asphalt requires warmer weather and prefers drier weather,” Hecox said. “When you have water and colder weather, it complicates the behavior of the pavement.” He said crews may have to put asphalt down in chunks and may have to go back over it with a paver several times.

Federal highway officials said that roughly 60,000 vehicles a day travel that segment of the George Washington Parkway. They estimate that roughly 100,000 vehicles were affected by the closure of the GW Parkway on Tuesday morning.

Hecox said that when that portion of the GW Parkway is “out of commission, those drivers are forced onto other routes.”

“It could be that 100,000 drivers are inconvenienced by this little hole,” he said. “It is all the more reason for us to work quickly.”

He said a crew of roughly a dozen people is working to repair the roadway. “It is a heavily traveled route,” Hecox said. “We can’t afford for that road to be closed for that long.”

He said the Federal Highway Administration learned of the sinkhole around 7 p.m. Monday. Crews had to wait until daybreak Tuesday to get a better sense of the size of the hole and figure out what equipment would be needed to fix it.

The exact cause of the sinkhole is unknown, but Hecox said it could be “due to geological structures underneath” or potholes. He said the recent warm — and then cold — temperatures in the area can also create something that is known as a “freeze thaw,” where pavement expands and contracts. “That can aggravate existing potholes and make it bigger,” he said.

Updated at 9:58 a.m.

Highway officials said the George Washington Parkway southbound lanes will likely remain closed for Tuesday evening’s rush hour and not reopen until Wednesday morning.

At 9:54 a.m., Federal Highway Administration officials said equipment was coming from another project on the Clara Barton Parkway and work to fix the sinkhole on the GW Parkway’s southbound lanes at Route 123 would begin “within the next hour.” Officials said workers would begin to remove pavement and backfill the hole Tuesday afternoon.

Doug Hecox, a spokesman at the Federal Highway Administration, said the conditions of rain are “not favorable” for fixing and repaving the sinkhole. But he said, “given the tens of thousands of drivers that cont on that route, we’re going to pave in the rain anyway. It will be a rough, ugly patch.” He said it is possible that the southbound lanes of the parkway could open Tuesday but “for now, we anticipate it will be open Wednesday morning.”

Officials also closed the ramps on Interstate 495 of both the inner and outer loops to southbound George Washington Parkway at Exit 43 until further notice so crews could repair the roadway.



Sinkhole along George Washington Parkway south at Route 123. (U.S. Park Police)

Earlier post:

A sinkhole has closed the southbound lanes of the George Washington Parkway at Route 123 Tuesday morning and caused several miles of traffic backups in the surrounding area. The roadway will be closed in the southbound direction until at least noon, federal highway officials said.

The southbound lanes are closed between Route 123 and Spout Run Parkway.

The hole at its surface, according to U.S. Park Police officials, measures roughly six feet wide by three feet long. But federal highway officials said their engineers have found that the size of the hole below the surface is larger. Hecox said just before 9 a.m. that the sinkhole measures 25 feet wide by 3 feet wide “from one side to the other side.” He said there is a “bigger void below the visible hole.”

“You’re just seeing the top of the hole,” Hecox said. Engineers on the scene, he said, are saying the sinkhole is 25 feet wide “from the furthest part of the void.”

“It is a big empty spot,” Hecox said. “There is a larger hole. A lot of that is underneath the pavement and you can’t see it.”

The sinkhole was discovered around 7 p.m. Monday when there was a crash involving four vehicles along the parkway, according to Sgt. Lelani Woods, a spokeswoman for the U.S. Park Police. There were no reports of injuries. Woods said it is possible that the hole may have started as a pothole and gotten larger because of weather conditions.



Another view of sinkhole at GW Parkwy south and Route 123. (U.S. Park Police)

On Tuesday morning, there were reports of several miles of backups on the GW Parkway and some surrounding roads. U.S. Park Police advised drivers to use alternate routes into the District, including Clara Barton Parkway, Route 50 and Glebe Road. But some drivers reported traffic was backed up along those roads as well.

Metro said its buses in the Rosslyn area are having to take alternate routes because of the sinkhole problem. At 8:30, its buses on the 15K and 15L routes were running up to one hour late in both directions.

“Traffic is backed up,” Woods said. Traffic southbound on Route 123 is bumper-to-bumper and commuters are seeing tail lights, as far back as Interstate 495, she said. Drivers are advised to avoid the area.

Virginia Department of Transportation officials said just before 8 a.m. that there were roughly four-mile backups along Interstate 495 north as a spillover from the GW Parkway closure.

GW Pkwy users: With traffic diverted to 123 for sinkhole repairs, consider alt routes to DC from Beltway--50, Clara Barton, Glebe, etc. — VDOT Northern VA (@VaDOTNOVA) December 2, 2014

ICYMI, from Nat Park Service: MT @WTOPtraffic: GW Pkwy S diverted to VA-123 S thru Tues am rush for emergency road work #VATraffic... — VDOT Northern VA (@VaDOTNOVA) December 2, 2014

AVOID: G/W Parkway SB CLOSED btwn Rt 123 + Spout Run Prkway, THRU RUSH, sink hole #vatraffic #dctraffic @ABC7Bri pic.twitter.com/sFcZrY9vCL — WTOP Traffic (@WTOPtraffic) December 2, 2014

Sinkholes often open unexpectedly and can cause major damage. In April, a street in the Charles Village neighborhood of Baltimore collapsed, washing away cars and flooding CSX railroad tracks.

Here’s a look at sinkholes around the world.

Original post at 5:11 a.m.

A major stretch of the southbound lanes of the George Washington Memorial Parkway in Arlington and Fairfax counties is closed Tuesday morning because of a large sinkhole.

The sinkhole developed Monday night. The GW Parkway is closed between Route 123 and Spout Run Parkway. The sinkhole is located just south of Route 123.

The closure is expected to last through Tuesday morning’s rush hour, according to the U.S. Park Police. The northbound lanes of the parkway are open.

Just a reminder! GW Parkway SB CLOSED between 123 and Spout Run. Get off on 123 and take Old Dominion. @nbcwashington pic.twitter.com/nWdTxKB4e6 — First4Traffic (@First4Traffic) December 2, 2014

Southbound GW Parkway? Nope. 30x30 sinkhole approaching Spout Run forces exit at Rt 123. Take Chain Bridge instead pic.twitter.com/yiFCyigzy9 — John Domen (@JDDsays) December 2, 2014

Large sinkhole closes traffic along southbound George Washington Memorial Parkway http://t.co/61W1v0sLrp pic.twitter.com/WZ3bfvzCFN — FOX 5 DC (@fox5dc) December 2, 2014

Officials are warning drivers to avoid the area. Drivers can get onto the GW Parkway from Spout Run Parkway. Officials have advised that drivers take Chain Bridge Road as an alternative.