One lane of northbound traffic remained open until 3:15 p.m., when all lanes were closed to remove the truck. The southbound lanes were also closed for about 45 minutes.
The delays for northbound drivers were compounded once the truck was removed and crews discovered it had dropped its load of frozen Alaska king crab onto the road.
SDOT officials opened a lane of northbound traffic about 6:30 p.m., and the second lane was opened at 8:30 p.m., after crews repaired damage to the guardrail.
Video from the scene shows heavy equipment scooping boxes and loose crabs from the roadway.
SDOT spokesman Norm Mah said the crabs were placed in a pickup truck by a front-end loader and then hauled to a dumpster for disposal.
There were no injuries reported from the crash and SDOT officials said engineers examined the viaduct and verified that it remained structurally sound.
It's a crabby commute after a semi hauling frozen crab overturned on the Alaskan Way Viaduct! One NB lane has reopened - http://bit.ly/1UEyy9aPosted by KOMO News on Monday, April 4, 2016
Pack your patience and don't drive "shellfishly" - 1 NB lane is open, and 1 will stay closed due to Viaduct guardrail damage: http://bit.ly/1UEyy9aPosted by KOMO News on Monday, April 4, 2016