Sand and water bathtub overflow when washer runs in basement

[Jeff White]

Hi Guys, 

I'm having an issue with the basement unit tenant stackable washer/dryer overflowing into the bathtub drain.  

I had a contractor put in a washer dryer down there about two months ago, and it connects to the shower, but everytime the washer runs, it discharges this sand/buildup material.   When the shower runs, it drains perfect fine.

Initially, I thought it was just something leftover from the construction and it would clean itself out.  Not sure if I should call a plumber or try to do something myself with a snake or something else.  

I've included a picture.    Thoughts?

[Jon Holdman]

You have a break in your sewer line.  Get it scoped and look at the video.  The washer is pushing water out faster than it can drain and that's causing the backup into your tub.  The sand is getting circulated back from the break into the tub.  If you're lucky, the break will be a simple one that's outside the house.  Or, could be the whole drain line is bad.  Really, really common around here for houses that have clay pipe.  The clay is now old enough that its shifting and collapsing and it has to be replaced.  Could also be a break under the house.  Not so bad if you're on a crawl space, tougher if you have a slab.