It's as if you were washing something away and it drained down the sink or bathtub drain. It's gone, it's not coming back, and there's no sense trying to get it back.
The past tense of "drain" is "drained."
The past participle of drain is drained.
Your kitchen sink drain and your shower drain are connected to a common drain line. There is some sort of blockage in the drain line past the point where the shower drain ties in. You need to call a plumber to run a snake through the drain line from the kitchen to where it ties in to the main drain of your house.
In this usage, "bathtub" is an adjective, modifying the noun "drain."
The sewer
form_title= Bathtub Drain form_header= Fix your bathtub with help from experts. When did your drain stop working?*= _ [50] Does that bathtub drain empty water too slowly?*= () Yes () No Do you own or rent your home?*= () Own () Rent
The sewer line is plugged or collasped. The sink and bathtub may drain because they drain at a slower rate. Toilet is all at once and the drain can't handle it. Water has to go somewhere so it backs up in the sink and tub.
A clogged bathtub drain can be a frustrating issue, leading to standing water and unpleasant odors.
You apparently have a creative drain system in your house. Your kitchen sink and your bath tub drains are tied together on the same branch flowing to your main line. I am assuming the toilets are not bubbling or overflowing when the kitchen sink drains. If they are, your main sewer line is clogged. If not, you need to have someone (preferably a plumber) run a cable or snake, as some people call it, through the kitchen sink drain.
Its your bathtub drain.
YES, you do need a trap. Usually the bathtub drain is on the same sewer line as the nearby toilet.The smell from the toilet's discharge will sneak up through the bathtub's drain line without a trap ... not pleasant!.