Washing machine grey water

[bsa0021]

I looking for some advice on removing my washing machine water from my septic system. My laundry is on my first floor which currently runs to the basement and into the drain system. My plan is to run another pipe through the floor and out the side of the house just above the sill plate. My concern is how much does the pipe have to drop (Slope) as it exits the house. I don't want the pipe to exit higher than needed since I am exiting the front of the house. Is the flow from the washer strong enough to push the water outside even if the pipe is level? I'm planning on keeping the exsisting drain system intact if it ever needs to be returned to the original configuration.

 

[rowerwet]

I have a pvc ball valve with a T above it in a vertical drop from my washer drain, I close it for the summer and divert the water into my gutter drain pipes that disperse the water along a lilac hedge, for the winter I open it and cap the diverted side to keep it from venting the septic tank.
I don't think the slope is that big of an issue from the washer, as the water only has some lint and sand in it from what I have seen, slope is more for #2, and kitchen waste like grease and food scraps.

 

[bsa0021]

I guess I was hoping I needed more slope to make the job easier. If slope was an issue, I could run the drain along the wall behind the washer and out the house about 6" above grade. Or, the hard but more aesthetically pleasing route by opening the wall, dropping the pipe into the basement and out the house about an inch above grade.

 

[benjamin]

1/8" per foot minumum, maximum slope is vertical.

Some say that if it's too steep the liquids will outrun the solids, but I say that's purely theoretical with plastic pipe and especially with laundry water.

 

[bsa0021]

Do I need to install a trap in my vertical pipe before the horizontal sloping pipe?

 

[benjamin]

only if you want to stop airflow. usually the trap is put where the machine discharges. and a elbow from vertical to horizontal should be of the long radius type, but we're past that point of formality on this one.

 

[Dune]

Even a level pipe will drain, (what else could the liquid do but run out of the pipe?), but the plumbing code calls for 1/4" per foot for pipe under 4" dia., and 1/8" per foot for pipe 4"and larger.

 

[ROBERT F]

We did same deal in house in Arizona, till pack rats made a home in the pipe while we were on vacation. Washing machine filled the pipe, and the laundry room. the lint build up in the grass was astounding too! and then the one time she washed all the whites in bleach, and the grass didnt like that at all either.

 

[bsa0021]

Minor issues when you consider the cost of replacing a septic system. I'm planning on putting a lint catch on the washer hose before it goes in the drain. I don't use bleach (it weakens elastic on socks etc.). And I plan on running the pipe into a dry well under ground which will prevent rodents in the pipe.

 

[billb3]

We have a grey water dry well and leech field. ( the tank was too small so added some pipe for extension )
clothes washer, dishwasher and kitchen sink ( other end of the house)

It's old so I have no idea about being code or not, except it doesn't leak.

I've had to clean out plastic pipe. Follow the pitch rules. Sand piles up just like it does in the ocean.
Put a trap.
Chipmunks and mice like pipes for highways.

Plus it might keep natural gas out.