Two catch basins in the Storrow Drive tunnel became clogged early this morning and overflowed, flooding the tunnel and causing a massive traffic headache for morning commuters, officials said.
State Police notified the Department of Conservation and Recreation around 1:30 a.m. after a trooper noticed the melted snow pooling in the tunnel, said William Hickey, DCR spokesman.
It remains unclear how much water accumulated, but “it was certainly enough to cause a public safety concern,” Hickey said.
DCR officials arrived at the tunnel at 5:30 a.m. and closed both lanes on the eastbound side at about 6 a.m.
Crews have been pumping water out since this morning, and the left lane was reopened around 9:30 a.m., once enough water was removed.
Both lanes are expected to be open by the evening commute.
The two catch basins were choked with debris, officials said.
DCR workers clean catch basins along Storrow Drive biannually, Hickey said. He said he wasn’t sure when the two problematic drains were last cleaned.
The DCR had planned to close one lane of the tunnel at 10 a.m. today to start a pothole repair, but the work was unrelated to this morning’s flooding problem. “Separate issue,’’ Hickey said.
According to the boston.com traffic service, cars at one point were backed up on the eastbound side of the road into Newton and beyond.