Utility Sink plugs up - bad design?

[GMZoo]

I have very little experience with plumbing. I have a 10 yr old home with septic located on east end of house, kitchen-laundry-garage utility sink on west end of house. Also garage where utility sink sits is lower elevation than kitchen/laundry by about 4' 2". Laundry plumbing shares wall with utility sink. Utility sink plumbing comes directly out of cinder-block garage/foundation wall, making it difficult to see or get to. Utility sink regularly clogs, and has been cleared by several plumbers. Water originally seemed to sit directly in the utlity sink drain, almost leeching into the tub. Each time, plumber indicates major update to utility sink plumbing is required to fix this "RIGHT", expensive due to cinder-block install. Last visit, the plumber raised the utility sink using 4x4 blocks under the four legs. This helped the standing water problem, but again the drain is clogged and won't clear with plunger.
Plumbers have indicated that laundry drains into west end of yard vice into the septic system. How is this determined? What should I look for to confirm? Suspect this is not true because kitchen waste seems mixed in with laundry water when it backed up again last night. Kitchen waste should be going to the septic, we believe....

I could add picture, if requested.

[Gary Swart]

It sounds to me like there the drain is not sloped enough. A drain needs to be sloped by at least 1" per 4 feet of length, and while more is OK, it should definitely not have dips with high spots. It's pretty basic that water will not flow up hill under gravity. Years ago, my father had a home with a basement drain under the slab that did not have enough slope. It required clearing about once a year due to accumulation of debris. Proper repair would have required very costly concrete removal to redo the slope. Realize that (a) this needs to be professionally done, and (b) professionals do not come at bargain basement prices, this will cost you some $$. To state what should be obvious, this is NOT a DIY job, especially for a novice. The plumber that raised the sink improved the slope away from the sink, but did not go nearly far enough. You've already had this advice from the plumbers, there's no magic fix-in-a-can for $19.95 plus shipping that will make this go away, nor is there any secret trick that will remedy the problem. I'm sure you were hoping for advice that would tell you how to DIY this for cheap, but sometimes, you just have to bite the bullet and pay the man.

[jimbo]

I have seen lots of old garage sinks which drained to some kind of drywell, or even just out into the yard! Sounds like your sink gets more usage than such an arrangement will support, and of course today it is completely NOT allowed by code. I suspect it would NOT be grandfathered if your local official find out about it.

A camera inspection would reveal more details, but the cost of that ( few hundred) might be better spent on just having a proper drain installed.

[jadnashua]

There are self-contained pump+basins designed to get around moving the drain water to the proper drain - check out Liberty Pumps for some choices. Ideally, though, you'd fix things so gravity could do its thing without assistance by the pump. I used one of these at my mother's house for her utility sink/washing machine in the basement since the outlet to the septic tank was about 4' higher and there was no way gravity could do its thing. Something like this may solve the problem: http://www.libertypumps.com/Products.../Product/?p=19

[hj]

From your description, I do not really have any idea what your situation is or why the sink plugs frequently, BUT I am also not sure if the "plumbers" know what they are doing.

[GMZoo]

Thanks for these notes on my problem. Does anyone know how I can tell if the drain is going somewhere OTHER than my septic system which is on the opposite end of the house (as noted by prior plumbing visits) ? If my kitchen 'waste' is going somewhere other than the septic, this is a problem I need fixed, regardless of the plugged drain in the utility sink, right??

[jadnashua]

A good plumbing shop will likely have a sewer camera. With one of those, they can also record which will show the condition and help you locate where the lines go. I think I've read that that can be combined with a locator beacon to help pinpoint things even better.

[GMZoo]

Thanks for these updates. I went under the house to my 'clean' crawl space, and sure enough, the drainage system is very clear and simple. The slope of the entire system is fairly shallow, which may contribute to the clogging. The laundry and utility sink go right into the main line, NOT the other direction as we had been told by several plumbers... From the utility sink entrance to the wall, I snaked the drain to 25' which didn't help. I got a 50' snake, also no luck. Ended up cutting into the main drain under the house at about 1/2 way along the main line (about 42') and snaking from there, which DID clear the pipe. And Oh-So-Messy.... at least it was food crud... I installed a 'T' so that we could snake from there if needed, without cutting the next time. I got a recommendation to use 'THRIFT' to clean out the rest of the gunk, and would love to hear opinion on that product if you have any experience with it. Two full days after completion, there is no clog and no leaking under the house, so I think I've cleared that hurdle and hopefully we can keep it clean. Please comment on 'Thrift'.