Home of the BrewNosers

I just moved to a house with a septic system and have a couple questions for brewers in a similar situation.

1) yeast slurries - Is dumping the yeast slurry down the drain going to cause a problem? I'm concerned that I might throw off the balance of the bacteria in the tank and septic field.
2) sanitizers - I imagine bleach is a big no, but what about StarSan?

Thanks

You've just given more thought to you septic system than 99% of the owners out there.

I'm on a septic and I've never considered any of these points...let's hope they don't cause issue because I may be in trouble if they do.

KMcK wrote:You've just given more thought to you septic system than 99% of the owners out there.

I don't want to be pumping the tank every year!

Oh, apparently, StarSan is safe - I'd have to dump 20+ liters (undiluted) straight down the drain all at once.

That's a great question. I've only had a septic system for two years so I'm no pro but one common theme is people keep recommending I dump a product into to encourage the break down of the solid wastes... this was what the previous owners used so I kept on using it.

http://septobac.com/" onclick="window.open(this.href);return false; it's available at local stores like SuperStore and Walmart

I was told to stay away from bleach and harsh chemicals so go easy on the star san....

Seems there's no real definitive answer. I'd often wondered about this myself and came across this. The most interesting part is:

I've asked the local septic guy after that thread and he got a big chuckle and asked just how much yeast does the average HB really dump. The yeast does have a tendency to stick to the pipes but by doing a double flush your safe.

Been dumping most of my yeast into the septic tank since starting brewing with no problems, roughly 3gals of yeast so far this year alone.

but then another post says:

Yeast is terrible for sewage systems. Organic waste has a value called BOD, or Biological Oxygen Demand. Bacteria consume oxygen while decomposing organic waste. If the waste has a high BOD, then the bacteria consume too much dissolved oxygen and potentially deplete it.

Yeast has a BOD much, much greater than even feces, and puts a huge, undesirable demand on the sewage system. Sewage system people no likey that.

Might be worthwhile giving a couple different septic disposal companies a call to see if you can get a straight answer. Septic backup is not a fun thing to deal with at all.

You could always beach your yeast, let it sit overnight for the chlorine in the bleach to evaporate and then dump it down the drain. Dead yeast don't hurt anything.

I had a septic system for 18 years. I dumped yeast, bleach and cleaner down the drain with no problem. We did have the septic tank pumped every 3 to 5 years. It passed inspection with flying colors when we sold the home.

JLC

jeffsmith wrote:Seems there's no real definitive answer. I'd often wondered about this myself and came across this. The most interesting part is:

I've asked the local septic guy after that thread and he got a big chuckle and asked just how much yeast does the average HB really dump. The yeast does have a tendency to stick to the pipes but by doing a double flush your safe.

Been dumping most of my yeast into the septic tank since starting brewing with no problems, roughly 3gals of yeast so far this year alone.

but then another post says:

Yeast is terrible for sewage systems. Organic waste has a value called BOD, or Biological Oxygen Demand. Bacteria consume oxygen while decomposing organic waste. If the waste has a high BOD, then the bacteria consume too much dissolved oxygen and potentially deplete it.

Yeast has a BOD much, much greater than even feces, and puts a huge, undesirable demand on the sewage system. Sewage system people no likey that.

Might be worthwhile giving a couple different septic disposal companies a call to see if you can get a straight answer. Septic backup is not a fun thing to deal with at all.

I read that thread too... I'm more confused than when I asked the question John's real-life experience is good to know, but Fishdisease's idea makes good sense. I imagine I'll just try and avoid chlorine based sanitizers and weather permitting, dump the trub and yeast (that doesn't get harvested) onto the compost pile.

Yeast is terrible for sewage systems. Organic waste has a value called BOD, or Biological Oxygen Demand. Bacteria consume oxygen while decomposing organic waste. If the waste has a high BOD, then the bacteria consume too much dissolved oxygen and potentially deplete it.

Yeast has a BOD much, much greater than even feces, and puts a huge, undesirable demand on the sewage system. Sewage system people no likey that.

I'd err on the side of caution and go with this post. We all know from experience that yeast consume a lot of oxygen and if the volume you discharge is enough they could, combined with the bacteria, make your system go anoxic. The bacteria would likely die and the yeast would go dormant. When more oxygen gets flushed into the system the yeast would likely take over and you'd have Coors Light coming out the other end.

You wouldn't want that, now would you?

KMcK wrote:You wouldn't want that, now would you?

No I would not! I'm gonna try my best to dump it all on the compost pile. I'm sure I will have a few episodes where I forget (or I'm just plane lazy), so its heartening to know that others have avoided catastrophe with a lot less dilligence.

I've been dumping my trub on the compost pile for a few years and have wondered about the sensibility of that. Am I cultivating some mutant hybrid yeast that's now spreading around the neighbourhood? If I use it on my hops will it come back to haunt me in a future beer? Will I be able to produce some really crazy lambics in the future?

You just gotta love the artificial intelligence at work in computers these days:

Yeast will eat the oxygen, it's one of the concerns of waste treatment systems with breweries. I have no idea how much it would take to influence your system but I'd dump it out in the woods or something to be safe. Yeast and trub are pretty acidic so it may interfere with composting as well, not sure. I dumped the trub out of a 15 gallon batch on my mother's lawn out back once. Once. Grass didn't grow there for 2 years So yeah, dump it where you don't want to mow

If you have any spruce or cedar on your property, dump it there. They love high acid soil and the nitrogen in the dead cells will give them a boost.

Thanks Nash - good to know.

mgc wrote:If you have any spruce or cedar on your property, dump it there. They love high acid soil and the nitrogen in the dead cells will give them a boost.

There are a few cedars - a couple too close to the house (I'm concerned what they'll do to my foundation). In the back field there are shit loads of spruce - I'm sure if I look I can find a few closer to the house.

Hi,
I'm on a septic and I dump all my yeast, sanitizers etc in the woods out back. Why take chances? It only takes a minute to walk out and dump it. Basically if you feel the need to ask someone if its okay, you already have the feeling its not. My neighbor had a problem with his septic (non brewing related) and it cost him $20,000 to repair/replace. I don't have that kind of coin lying around.
Tim

FWIW there's an engineer on the forum who deals with septic systems and drainage. He may be able to answer your questions. Hint: he's one of the original club members.

I'm with John (or Anita). I do try not to put _much_ bleach down the drain, but I've never worried about yeast. otoh, I figure yeast is a good nutrient for the garden, so it usually goes straight there.

I suppose, technically, the guy who said yeast has a huge BOD is correct - but it is only going to consume O2 in the presence of sugar. I doubt an awful lot of convertible sugars go down the drain. And anyway, "Sewage system people no likey that" must be untrue - they love anything that fucks up your system: it's money in their pockets.

There's a huge difference between what I might put in my septic system, occasionally, and what a commercial brewery would be dumping

Ive been on a septic for about 9 years, I have it pumped every 2-3, i dump all my yeast/trub etc. down the drain.
If i dump my sanitizer I dilute it greatly. I havent had an issue but i do like the idea of killing the yeast first.

I always thought of the yeast as food for the septic, i never really thought of it as competition to the bacteria, thats why i am a physical/analytical chemist and not an organic one

derek wrote:I suppose, technically, the guy who said yeast has a huge BOD is correct - but it is only going to consume O2 in the presence of sugar. I doubt an awful lot of convertible sugars go down the drain.

What if Andy is diabetic from all the beer he drinks?