Water softener gray water drain

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Ashful

Minister of Fire
Mar 7, 2012
20,042
Philadelphia
Noting some pretty serious corrosion of my 12 year old concrete d-box, and just guessing how much damage it's done to my septic tank over the last 30 years, my septic tech suggested I get our water softener off the septic system. Trouble is, that system is in our basement utility room, surrounded by house or patio on three sides, with the only exit being thru a 2' thick granite wall on the fourth side.

I do have a 4" drain line that runs around most of the perimeter of the house, which I believe to be all non-perforated, it catches water off all of our downspouts and tees into a 6" line that runs to a storm drain. I could run a 2" line from outside this utility room, and tee into this line at the nearest downspout drop, about 60 feet away. It's a job, but nothing insurmountable.

But penetrating this foundation wall below grade is going to be a serious "thing". Plumbing thru the wall above grade ain't the prettiest thing, but it's hidden by some landscaping, and could be done if it doesn't create two problems:

1. Freeze potential.
2. Air gap violation.

On the air gap, I'm assuming that I'd still want some sort of air gap, preferably outside the structure, in case the line backs up with storm water. We occasionally get big rains, which by my calculations when combining all of the various roofs and patios tee'd into this line, are coming relatively close to the total line capacity. The water softener is a piss in the ocean in this net capacity, but I don't want a backed up drain to flood our basement during a tropical storm, either.

There's no windows in that portion of the basement, but I believe grade is almost plumb with the sill, or perhaps just a few inches below. There's some slope down to the next downspout drop, so I could get this line down a few feet below basement ceiling height, but again... penetrating 2 feet of granite with much more than a 1/2" line is going to be an absolute nightmare.

Thoughts?
 
Yeah you definitely want that out of your septic system...that's a no no.
Hard to say on how exactly to get it out of your house, without being familiar with the place...sounds like a challenge for sure.
Our water softer discharges out through the wall above grade and into a downspout pipe...no issues with that.
 
Yeah you definitely want that out of your septic system...that's a no no.
Hard to say on how exactly to get it out of your house, without being familiar with the place...sounds like a challenge for sure.
Our water softer discharges out through the wall above grade and into a downspout pipe...no issues with that.
Ours runs overnight, like most I suspect. We're often below 20F at night, and occasionally below 0F. Just worried it might freeze up between runs with an above-grade penetration, as the cycle starts and ends with fresh water, brine only making up one middle phase of the cycle. No issues for you in Ohio?
 
No issues for you in Ohio?
Nope, it has fall on it the whole way once it goes through the wall...so no water left to freeze.
 
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Okay, then it looks like I have a goal! Will try to measure elevation and sketch up a cross-section, to get this figured out in the next few days.
 
You can tee in a vacuum breaker (or an inverted check valve) at the high point of the discharge line to ensure that it drains completely.
 
Codes around my place say everything has to go into septic I find this to be stupid I do not understand their reasoning for this. Grey water like softner and washer I would like to just send to a dry well system.
 
Codes around my place say everything has to go into septic I find this to be stupid I do not understand their reasoning for this. Grey water like softner and washer I would like to just send to a dry well system.
I guess I need to do more digging on this, and then if it doesn't agree with the goal of preserving my septic system equipment, decide if I even care. What I found in just a few minutes of digging is that there seem to be at least as many localities with code preventing the discharge of a water softener into a septic system, as ones who require it.

I may have added confusion in using the term "graywater" in my post title, as it seems the discharge of a water softener backwash may not be considered graywater, by some definitions of the term.

This article doesn't answer the question at hand, but lends some motivation to my original point: https://www.waterworld.com/home/art...ptic-systems-and-the-problem-is-easy-to-solve
 
I am planning the same project on our Northwoods build. No softener installed yet, but my plumber gave me an insane quote for a softener and dedicated drain that doesn't go to the septic and advised against running to the septic. My inspector told me to just keep the drain field 25' away from the well. I think I'm going to dig down, core through the foundation and put in a dispersal basin seeing as we haven't done any landscaping yet...
 
Have you researched how that dispersal basin will affect the surrounding landscaping? In my case, the well is adjacent to my only potential outside wall, so I'll be routing into a drain that goes around the house, anyway.

Some seem to like to run the softener drain to the septic system drain field, bypassing the septic tank, but I was planning to just run it to a storm basin at the back of my property. It'd be a drop of piss in the ocean, as that storm basin joins all of our regional road run-off. The salt coming off my softener system ain't even 0.0001% of what they put on our roads, every time there's a forecast for any winter precipitation.
 
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Bottom of the basin will be 4' minimum below grade, so I doubt it will affect much. If it does I'll have a patch of dead grass... Oh well. Haven't decided if I will or won't put a surface drain on it. That would help with some of the surface runoff coming down the hill, but I fear it might also make it more likely for the basin to freeze.
 
Some seem to like to run the softener drain to the septic system drain field, bypassing the septic tank
I was thinking you could do something like this after replacing the distribution box with a plastic unit.
There's a lot of salt in urine anyway that's not removed in the septic tank.
 
Maybe just discharge it to your salt water swimming pool... :p
 
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I have similar problems with basement below ground. I use slump pump and 5 gallon bucket for the Water Softener to pump into for flushes. It all goes to 55 gallon barrel. Lasts about 20 years or more until it fills up with junk from laundry sink. Barrel has holes and gravel under and beside it.

DSCN1414.JPG
 
I was thinking you could do something like this after replacing the distribution box with a plastic unit.
There's a lot of salt in urine anyway that's not removed in the septic tank.
Hah... they actually switched me from a plastic D-box to concrete, 12 years ago! Box is so deep that the plastic one caved in under the load of the dirt atop it. If I could do it over, I'd probably choose a plastic box with a larger concrete plate bridging over it and distributing soil load around it, but since I just finished two days' work of digging it up, re-burying it, and cleaning up that mess, I ain't going back in now!

I do think the storm drain system is the best route. Like I said, it already handles more brine coming off our road in each and every winter storm, than my softener will put into over the course of an entire year.
 
Our softener and iron remover discharge above grade to a dedicated drain line that's buried approximately 12"-6" below the grass. It is approximately a 50' run before a surface termination at the base of some large trees. In the 5 years I have had no freezing issues, the water dissappears in an hour or so (guessing 20gals or more discharged) the grass under the spruce trees does fine, not sure how it affects the spruce trees? I think you are completely fine to exit above surface and tie into your downspout. I have mine set for 5:30pm to be able to "be around" if something acts up. I prefer this over a middle of the night problem to deal with.
 
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I was thinking you could do something like this after replacing the distribution box with a plastic unit.
There's a lot of salt in urine anyway that's not removed in the septic tank.
It’s the concentrated amount of salt brine that hits the concrete during the regeneration process that causes the erosion. Urine is often dilluted when it hits the system.
 
When I bought my house, mine was routed into the septic. You could see the damage it caused, although it wasn’t much, but it was visible. I re-routed it to a dry well in the other side of the back yard. It goes through the block just below grade. I’ve often worried about freezing also. But we’ve had the coldest weather in years at times this year, and I’ve had no issues. You could also manually regenerate the system during the day when the sun is out and it’s warmer if you were really concerned about it freezing. But I would def do something to get it out of the septic. That salt brine is bad stuff
 
That concrete dbox could just be a crappy dbox. There’s always a pocket of sand in the mix!

Definitely don’t run the backwash into the septic.
 
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How often is your water softener regenerating and have you measured to see how much brine it is outputting?
Will take me a bit to calculate this. Stand by...
 
There's a big spike in electric usage on the well pump circuit near my scheduled regen time every 6 days on average, so that's likely where our water usage is putting it these days. I have one kid to takes "forever" showers, and a wife nearly as bad.

I've used 0.93 ft3 of solar salt pellets in 47 days. I think these pellets come in somewhere around 63 lb/cu.ft., so let's say ~1.25 lb. per day of salt, or 7.5 lb. per regen cycle.

If you want to know how much water is mixed with that salt, I have to do another calculation off the energy monitor, but I can only see total water used in that cycle. Figuring out which phase of the cycle (brine phase vs. rinse phase) goes with which fraction of water usage would be some real work.

I'll have to check after next regen to see capacity between regen's, i.e. how much water is used between each regen. Oddly enough, in scrolling through the menu just now, I see hardness had been set up to 15, whereas we only run 194 mg/L (11.3 grains) here. Now I'm not sure if I had dialed it up because I was seeing minerals in the output years ago, or if it was changed accidentally. But I just dialed it back down to 12 grains, which bought me 3x more capacity remaining before next regen (600 vs. 200 gallons). I do remember fiddling with this before, but didn't leave myself any notes other than a calculation of grains from total hardness on a water test.
 
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House has it going into Septic system. Update building codes says to do it into a Dry well. Septic tank guy says having it go into septic system keeps stuff like Soaps etc from hardening. Any way you look at it (dry well vs Tank) you are adding salt into the ground. Depending on your water table, it may be moot where it is. I have a very high water table so I assume that salt is being distributed throughout the yard. Simple 7th grade Science. High concentrations will diffuse to lower concentrations
 
I was just thinking you would need to know those calculations to size your dry well if you take that route. Would you be able to route the discharge hose into a 55 gallon drum to see your output? Might not be as bad as you think and other factors might be at play.
 
My dry well is a standard sump pump basin I got from Home Depot. It’s plenty brig enough. Just drill a ton of holes in the sides, cut the bottom out, and surround it w stone.