Make line features thick and yet not overlapping

[zhongying_gan]

Hello,

I'm using ArcGIS Pro 3.0.2. I would like to make a highway speed map that looks like the following:

You can see that there are two parallel lines for each freeway, because there are always two directions.

I have a line feature of California highway system in ArcGIS Pro. When zoom in, I can clearly see the freeways of two directions:

But after I zoom out, the two-direction lanes just merge into one:

I tried to make both lanes very thick, as shown in the first map (my goal), but the lines just overlap each other:

I was wondering if there is a way for me to make both lines thick and repel each other so that they are not overlapping? Any comments will be greatly appreciated. Thank you.

[DavidSolari]

Would a reference scale meet your needs? I can't think of any other way to control line sizes across arbitrary scales. If you have a set list of fixed scales you can create multiple copies of each line layer and hand-size each thickness to taste.

[SarahRijneke]

If the roads have been digitized in the direction of travel (i.e. right side of the street was digitized heading northbound, left side was digitized heading southbound) you should be able to use an offset.