Nginx Web Server - Home Directory Paths With Spaces

I am working on replacing an apache old home directory web server - users can host static files/web pages in their home directories. I'm sure that my approach is not prefect but it works except for any path that has a space in it. The home directories are split across a few different folders like so:

basedir   
└───faculty
│   └───user1
│       └───public_html
│   └───user2
│       └───public_html
│   │...
└───staff
│   └───user1
│       └───public_html
│   └───user2
│       └───public_html
│   │...
└───students
│   └───user1
│       └───public_html
│   └───user2
│       └───public_html
│   │...

My almost working solutions looks something like this:

location ~ "^/~(.+?)(/.*)?$" {
    set $userAlias "notfound";

    if (-d /basedir/faculty/$1/public_html/){
      set $userAlias "/basedir/faculty/$1/public_html$2";
    }
    if (-d /basedir/staff/$1/public_html/){
      set $userAlias "/basedir/staff/$1/public_html$2";
    }
    if (-d /basedir/students/$1/public_html/){
      set $userAlias "/basedir/students/$1/public_html$2";
    }

    alias '$userAlias';
    index index.html index.htm;
    autoindex on;
  }

The issue is that $userAlias does not get the normalized string, so any path with space tries to resolve a path with "%20" in it, which will not exist.

I am open to any advise.