Olympic Boulevard and Gangbyeonbuk-ro, the two major mountains of Seoul, are under control 
Near Heukseok-dong, Olympic-daero
There’s not a single car 
Under the Dongjak Bridge in Olympic Boulevard
Two-way control, as expected 
Near Noryangjin Fisheries Market in Olympic-daero
The same
If you look closely, the right side of the road is already heavily flooded 
Near Yeoidyo Bridge, Olympic Highway
First-round flooding 
Near Yeouido 2 Bridge, Olympic-daero
Two-way control, as expected 
Near the downstream IC of Yeouido, Olympic-daero
The wide road on the left is Olympic Boulevard
The flooded road on the right is Nodeul-gil 
Near Yanghwa River Civic Park on Olympic Boulevard
Two-way control, as expected 
Near Hangang Bridge on Gangbyeonbuk-ro
Two-way control. CONTROLLED 
Near Ichon Interchange on Gangbyeonbuk-ro
VEHICLE ENTRY CONTROLS HIGHLY CONGESTED
Olympic Boulevard Gangbyeon Expressway that runs east-west through downtown Seoul
It’s controlled in the middle
I’m on my way to work this morning 
Fortunately, it’s early in the morning when there’s not much traffic
As in 2011, the above mishaps did not occur
Source: I took a screenshot and wrote it