I want to make a road with a bordure as on the picture

Currently I do the next steps:

1. 2 main loop cuts vertically, 6 horizontal loop cuts for curving -> 2) Select horizontal edges and manually move each of them to the left -> 3) Additionally, accurate road width by moving vertices -> 4) Select faces and extrude them down

Is there another methods to do this, maybe more accurate/easier? Also, For example, I badly imagine what will I do if need to extend the existing area.

I want to make a road with a border as shown in the image below:

Currently I do the next steps:

1. 2 main loop cuts vertically, 6 horizontal loop cuts for curving

2. Select horizontal edges and manually move each of them to the left

3. Additionally, accurate road width by moving vertices

4. Select faces and extrude them down

Is there another methods to do this, maybe more accurate/easier? Also, For example, I badly imagine what will I do if need to extend the existing area.

I want to make a road with a bordure as on the picture

Currently I do the next steps:

1. 2 main loop cuts vertically, 6 horizontal loop cuts for curving -> 2) Select horizontal edges and manually move each to the left -> 3) Additionally, accurate road width by moving vertices -> 4) Select faces and extrude down

I want to know ss there another methods to do this, maybe more accurate/easier? Also, For example, I badly imagine what will I do if need to extend the existing area.

I want to make a road with a bordure as on the picture

Currently I do the next steps:

1. 2 main loop cuts vertically, 6 horizontal loop cuts for curving -> 2) Select horizontal edges and manually move each of them to the left -> 3) Additionally, accurate road width by moving vertices -> 4) Select faces and extrude them down

Is there another methods to do this, maybe more accurate/easier? Also, For example, I badly imagine what will I do if need to extend the existing area.