toilet backup to dishwasher Home › Forums › Public Forums › Drainage & Sewerage › toilet backup to dishwasher This topic has 1 reply, 2 voices, and was last updated 21 years, 11 months ago by Retired plbg1. Viewing 1 reply thread Author Posts 1 Dec 2002 at 1:44 am #279137 MasterPlumbersKeymaster If toilet is flushed, can it backup into the dishwather? Please explain how this can or cannot happen.[email]null[/email] 1 Dec 2002 at 1:11 pm #300108 Retired plbg1Participant It depends how it is hooked up. If the drain is connected to GD no because it is higher then toilet. Author Posts Viewing 1 reply thread You must be logged in to reply to this topic. Log In Username: Password: Keep me signed in Log In