On some interstate highways the line markings are white dashed lines followed by black dashes. Why black?

Question

I took a picture on I40 in North Carolina but cannot post it. These lines are intentionally painted. I have also seen them in PA.

Answer 1

The highway dept periodically repaints the lines in the roadway, when they do they have to blackout the old lines to keep the old and new from " bleeding " together otherwise it would appear to be one solid line after awhile...TAG

Answer 2

Makes them stand out better.

Answer 3

Covering the aging old white dashes?

Answer 4

I see that sometimes where the black is used to cover up temporary white lines used when lanes were shifted for construction.  Once the lanes go back, the temporary lines are covered with black.

Answer 5

It's to make the lane markings stand out against the gray color of  the concrete.

Answer 6

It's so that aerial troopers can see the lanes against the light concrete.  White stripes don't contrast well from a plane.  Ohio uses planes also and they do the same thing.

Answer 7

I have never seen black dashes....where can I see some? to me black dashes would be hard to see so ....I dont see why that color would be used...especially when its night time

Earth

Answer 8

The only time I've seen this is when they have had to paint over the original white line in black to match the asphalt due to some road work being done. Then when they repainted the white line they didn't match up and the black line shows in between. But that's just in my area. It may mean something else in another state.