Why is water coming up from the shower drain, and why does my toilet water back up into the drain?

If the P-trap is made of 2”ABS, fecal matter could not pass through the shower drain.If the drain becomes obstruction, you can clear it with aggressive plunging.

How do you clean the shower drain?First, pour a cup of baking soda down the drain, and then after a few minutes, add another cup.Give the mixture a few hours to work and then rinse the drain with boiling water.

A sewer line problem is when dirty water comes up in your bathtub.The sewer line goes from your toilet, sink, bathtub, and shower to the city's sewer system outside.Tree roots, flushed items, and grease can cause a sewer line problem.

Only a few drains will back up if the sewer line is in a secondary state.The water from the toilet is going into the shower.If the toilet and shower drain are in the main line, you will have issues with every drain in your home.