Basin / Location association

I think I know the answer to this question, but I'm asking to promote a discussion and standardization in the CWMS database.

Asking the question with Access to Water in mind.

Is there a way to get a list of basins, and then turn around and get a list of locations that are associated with that basin?

I am unaware of a functional basins endpoint (looking at the swagger docs). Even if that worked, the next need of actually getting a list of locations for each basin does not appear available. Location Groups looks interesting, but I'm afraid the application of groups, names, usage, etc would vary between offices and therefore not be consistent to pull at a national level.