St Mary of the Falls

Enter parking lot from Bagley Rd, just north of Columbia. The left set of doors (there are three) are the ones you want. After entering church, go up slant to the right and then turn right after going through the doorway. There are two gender-neutral bathrooms in the hall.

Be mindful that this is a church. They are, however, pretty progressive and you'll be welcome. The doors are open for only a portion of time every day - I would recommend using this as a backup if you can't find anything else local.