My house is 40+ years old and the sink drain and washer drain run together causing clogging monthly. I have to go to the roof to snake the clog constantly. I'm on a septic tank. Would a garbage disposal help push the water through the pipe which would help eliminate the clogging? I would not use it for disposing of the garbage since I understand that it is not good for the septic system.

A septic system is NOT like a common public sewer system. You have to be extra careful what you place in and down the drains. I would hire a licensed plumber that specializes in septic systems to determine the REAL cause of your blockages. It could be organic or non-organic. It could be the septic tank needs servicing. The horizontal line might be too level. The plumber will rule out, what its not.

Do NOT use chemicals.

Best Wishes

quote; I understand that it is not good for the septic system.

That is interesting, because I have used a disposer with my septic systems for over 35 years without problems, as have MILLIONS of other homes in this area.

If the kitchen is on a separate gray water, food waste can plug up the line quickly. An enzyme drain cleaner and a professional cleaning would be the best route.