Virginia Department of Transportation reopened two lanes on I-66 after an hours-long closure.
Over the morning commute, two westbound left lanes in Fairfax County were closed for emergency road work.
VDOT says crews scoping out the road discovered a cavernous hole looming under the pavement that measured 12 feet wide, 6 feet long and 6 feet deep.
"We did not want people driving on it until we could get it shored back up," a VDOT spokeswoman told News4.
The hole wasn't a sinkhole, she said. Workers found it as they did pipe work.
Crews filled the void with a sand and cement mixture then let the materials set before reopening lanes.
Originally, VDOT said the work may impact the afternoon rush hour. Fortunately for commuters, crews began picking up cones after 1 p.m.
Even during the typically slower midday hours, dense traffic slowed to a crawl as cars squeezed down to two lanes.
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