YES PLEASE! It is so annoying lol

We've logged this as I believe there should be a notification.

what do you mean you've logged this? i went through notifications menu 3 times and i can assure you, there is no such option

As in logged it as a bug to be fixed, I believe.

You already have the ability to disable the popups of the blockade messages.  Open the message and click the slider in the upper right. 

SpankydaMonkey wrote:

You already have the ability to disable the popups of the blockade messages.  Open the message and click the slider in the upper right. 

as i mentioned at the very begining, its simply doesn't work. the pop up keeps appearing every time the route is blocked

You are correct.  Each new blockade is generally different than any other so it will also popup.

I stand corrected after testing this further in my game.