Incident involved a tractor trailer.
Funding issues have strung out the set of three highway widenings inside the Capital Beltway.
Maintenance work will close a ramp leading from the Teddy Roosevelt Bridge (Interstate 66) for several hours each day over the next month.
All lanes have reopened.
A car fire is blocking both westbound lanes of I-66 at Glebe Road in Virginia, with delays expected to last for at least one hour.
A crash involving a Metrobus on I-66 closed lanes and snarled traffic as the evening commute got underway. Four people were sent to the hospital.
Officials said crews are working to put out the fire, which is impacting traffic at Washington Boulevard.
After a quiet morning, traffic is picking up on the region's main roadways out of town.