Water Level Mark at an Underpass in Haneda

This picture was taken on Ring Road No.8 in Haneda airport.

 

Here the road goes in a trench to cross some way in the airport. The problem is that heavy rain may change the bottom part of the road into a pond. These yellow and red horizontal lines on the wall are water level mark. My understanding is that the road will be closed if water reaches to the red line.

 

Done