where to download images to ?

I am keeping user's images of documents in an S3 bucket. When they first login I get all of their images and download them to my server. They are getting put into /app/assets/uploads/ etc. I am concerned about keeping user images mixed in with my code. I am using CI3 and Docker. Can anyone recommend a better place to keep user's images and tell me how I can create a path to these files in CI3?

proof that an old dog can learn new tricks