Yeah sure, but that will make your phone significantly bulkier
The Galaxy S5 is waterproof, has a rubber gasket over the charging port and a removable battery but not "significantly bulkier" compared to all of the current crop of mid-range/flagship phones - it's actually lighter than the glass-backed ones
1: https://www.ifixit.com/News/30845/your-phone-is-never-waterp...