Depends on the ditch. That's effectively how the Loon Lake Powerhouse was constructed. Traversing the entrance shaft funicular you can see the bobble where the upper and lower "ditches" deviated somewhat.

Upper American River Project, east of Sacramento.

https://en.wikipedia.org/wiki/Upper_American_River_Project

Video tour:

https://youtube.com/watch?v=LHYnxvp-hJY