D Nordlan

Thanks, everyone. Lots to consider...not sure what I'm going to do, yet. Will do some testing of water output this weekend.

Just fyi... We typically do around 5-6 loads of wash per week. We normally don't do more than 1 load per day, but sometimes 2 loads on a weekend day. To keep everything healthy (pump, sewer pipe, ground saturation, my nerves), and to occasionally use regular laundry detergent, I was planning on diverting every other load to the yard.

R Scott: Ah, interesting. About what size vertical pipe are we looking at, here? How many gallons would it need to be able to hold at one time?

I found a handy calculator here. http://www.handymath.com/cgi-bin/cylinder.cgi

EX: 6" pipe, 4ft long will store 5.8 gallons

Thanks for the replies.

I took a look at the owner's manual for my washer (LG WM2010C) but didn't see any specs for the pump, other than the total height of the drain hose should not exceed 96" from the bottom of the washer. The drain line that came with the washer is a gray, thin, corrugated plastic tube (3/4" ID).

I'll try to explain the details for my planned graywater system. (If not clear, I'll try to post some sketches.)

Washer: HE LG WM2010 located on ground-level on the inside of an external wall.

Inside: I would mount a 3-way valve about 1 ft from the top of the washer, then run a PVC pipe horizontally from the valve for about 4 ft, then out the exterior wall.

Continuing Outside: The PVC pipe would make a 90 degree horizontal turn along the outside wall for about 6 inches, then I would run a vertical pipe (with a T-connector) 6" up for the vent, then about 4ft down (with an inline swing check valve and a disconnect area) where it would meet the existing 3/4" pvc pipe that runs under the cement walkway.

Existing PVC Under Concrete: The 3/4" PVC goes vertically into the concrete about 4" deep, then makes a 90 degree horizontal turn to run the length of the walkway for about 12 ft. There is a 45 degree bend about half way. The 3/4" PVC exits the concrete about 8" from the fence line, about 4" below the top of the concrete. (I assume the contractor that poured the patio would have enured there was some sloping of the pipe. Water appears to be flowing well when we did some testing.)

Yard Irrigation Line (1): From 3/4" PVC extending from the concrete, we want to run a 25ft straight, slightly downhill-sloping pipe with 3-4 outlet areas, then a 45 degree turn for about 8 ft ending at the final outlet area. We will NOT have any trouble maintaining a slight downhill-slope along the entire length of the 'irrigation' line.

Outlet areas: 4-5 outlet areas. Each outlet area will be large mulch basins with bins to keep the pipe elevated. We will drill a number of holes in the pipe at the outlet areas, based on what the flow looks like during testing.

Hope this is clear! Thanks again.

Hi -- I'm setting up a laundry-to-landscape system and have a question about pipe sizing.

We have an HE washer (a few years old) that has a drain tube of 3/4" ID. We are also planning on hooking in to some pre-existing 3/4" PVC pipe that runs under a concrete walkway (a distance of about 12 ft). (This pipe has never been used, and this will be it's designated purpose. If we can't utilize it, we'll probably scrap the whole project, because we don't want pvc pipe exposed on this nice walkway.)

My question is: do I still set up the system with 1" pipe off a 1" 3-way valve, and also use 1" pipe into the irrigation areas? Or should I stick with 3/4" pipe throughout the whole system? I'd hate to blow out the washing machine motor or run into any other pressurization problems.

Thanks.