Mystery Greywater Drain
My house was built in 1956 and it has a greywater laundry drain which backs up. The pipe goes out the garage wall on the same side as the main drain and disappears under the sidewalk. My first assumption was that it went into the main drain, but when there is water flowing through it there is none visible in the clean-out connection on my main drain. Then I figured it was a greywater drain to the ditch on the side of my lot, but I can't find where it comes out or dig out the pipe in that direction. It has flow, but not enough to handle the washing machine draining. Other than breaking up the sidewalk, or digging holes all around my yard, what solutions are there to finding this mystery drain? Any suggestions would be helpful.