Septic Systems - Aerobic vs. Conventional

[plowking]

In NH,I see aeration systems ,mostly around lakes and lots that are considered unfit for conventional systems. These systems have a three compartment tank. First compartment is actual septic tank,second compartment holds the aerator,it is surround by a plastic media,third compartment is pump chamber or dosing[ settling] tank. The water quality going to the leachfiled is suppose to be drinking water quality,hence the reduced distances,setbacks and smaller footprint of leachfield. The aeration pump is mounted outside on a post or in the basement. I usually feel the conduit from the pump going to the tank,I believe it should feel warm if the pump is doing it's job....I did have a problem with earlier tanks, the screen or grill seperating compartments let the media fall back into the primary tank,it clogged up the hoses to the septic pumper when they[we] were servicing tank,new tanks have better design. The media can be shaped like hair curlers,other shapes depending on the manufacturer. Some of these systems have leachfield vents as well,I prefer the additonal venting . plowking

 

[Bird]

In NH,I see aeration systems ,mostly around lakes and lots that are considered unfit for conventional systems. These systems have a three compartment tank. First compartment is actual septic tank,second compartment holds the aerator,it is surround by a plastic media,third compartment is pump chamber or dosing[ settling] tank. The water quality going to the leachfiled is suppose to be drinking water quality,hence the reduced distances,setbacks and smaller footprint of leachfield. The aeration pump is mounted outside on a post or in the basement. I usually feel the conduit from the pump going to the tank,I believe it should feel warm if the pump is doing it's job....I did have a problem with earlier tanks, the screen or grill seperating compartments let the media fall back into the primary tank,it clogged up the hoses to the septic pumper when they[we] were servicing tank,new tanks have better design. The media can be shaped like hair curlers,other shapes depending on the manufacturer. Some of these systems have leachfield vents as well,I prefer the additonal venting . plowking

The Hydro-Action system I had installed in 1997 for $5,000 actually had separate tanks instead of just differnt chambers; a concrete septic tank, then from there into the fiberglass or plastic treatment tank, then to the dosing tank which was another concrete tank just like the first one. If I rmemeber right, the two concrete tanks were 500 gallons each while the treatment tank was 750 gallons. A stainless steel submersible water well pump was what pumped the water from the last tank out a 1" PVC line to a "T" then on to two sprinkler heads. Between the treatment tank and the final or dosing tank, there was a "basket?" in which I put chlorine tablets once a month.

 

[Bigfoot62]

What were people paying for the NORWECO systems back when you installed them?

You're gonna hate me for telling you. The first one that I installed, 1984 IIRC, was $3600 delivered. (my cost) Total charge for a typical installation run from about $4200-6000, depending on effluent discharge.

After the final treatment, is the effluent flowed by gravity into a leach field?

No leach field required back then. A few people wanted them, just to soak up some of the water. Some folks wanted a holding tank and sump pump so that the effluent could be used to irrigate the lawn or flower beds. Most would simply discharge into a natural drain or pump it a short distance to get it out of the way.

NORWECO actually sells and recommends bacteria treatments . . .

I said that I like the NORWECO treatment plant. I don't agree with everything they're promoting. I would guess that NORWECO, like most others, sells bacteria because there is a market for it. Not that it's needed, or even that it may be beneficial, but because it makes $$$$.
Another example of successful marketing is the automotive extended warranty program. ALL car dealers promote them. Most dealers try harder to sell you the ext. warranty than the car itself. Why? HUGE profit. The typical ext. warranty has a 200-300% mark-up. And, if you do the math, it goes in favor of the dealer. Rarely, if ever, are you going to have a "covered" repair that cost as much as you pay for the warranty. Now, the dealership isn't looking out for your well-being, he's just making $$$$.
I still believe that buying bacteria is like purchasing snake oil.

 

[dmccarty]

In the end it comes down to what works better and how much $$$ does it cost.

I have 3 options:

1 - Install the conventional system that is NOT aerated and have a system that is very inefficient, produces deadly gases, and because of it's anaerobic design will eventually fail. Cost = $7,000

I have not seen or heard of many conventional systems failing. Our conventional system does not stink. I sure am not worried about deadly gases. That is one of the reasons for plumbing vents. Heck, I could smell the gases, if the wind was right and I was in the yard, in our city house connected to the sewer. I have NEVER smelled gases from our system except when we had the tank pumped and that was not bad at all. The gases from the sewer in the city were worse.

Most of my neighbors would love to have a conventional system like us. They have continuing expenses higher than ours and they will have repairs. As long as gravity still works, our system will keep flowing.

You are going to spend $60 a year on power. Do you think this pump will cause the solids to be completely removed from the tank? Will you still have to pump the tank? If so why waste the money on power? In four years the power will cost you $240 which is far more than we pay to pump the tank.

Later,
Dan

 

[Pettrix]

I have not seen or heard of many conventional systems failing.

Most of my neighbors would love to have a conventional system like us. They have continuing expenses higher than ours and they will have repairs. As long as gravity still works, our system will keep flowing.

You are going to spend $60 a year on power. Do you think this pump will cause the solids to be completely removed from the tank? Will you still have to pump the tank? If so why waste the money on power? In four years the power will cost you $240 which is far more than we pay to pump the tank.

Later,
Dan

Conventional systems fail all the time. It is a fact that just by their basic design, they have a life span of 20-40 years, at which point they will expire/fail because the soil will no longer be able to filter the effluent.

A conventional/anaerobic system just by design produces methane gas because it is anaerobic. An aerobic system does not produce methane gas.

There still will be solids in the aerobic, it is just that instead of pumping every 3 years, you can extend that to 6 years and have a more efficient system. Out here it costs $650 to pump a 1,500 gallon tank. I would rather spend the $60 a year on power and extend the pumping interval.

 

[Bigfoot62]

Conventional systems fail all the time. . .

So do mechanical systems.

A conventional/anaerobic system just by design produces methane gas because it is anaerobic. An aerobic system does not produce methane gas.

There still will be solids in the aerobic, it is just that instead of pumping every 3 years, you can extend that to 6 years and have a more efficient system. Out here it costs $650 to pump a 1,500 gallon tank. I would rather spend the $60 a year on power and extend the pumping interval.

I don't mean to beat a dead horse, and it sounds like you have made up your mind. I understand your concerns and your desire to scrutinize the details. I'm a detail guy myself. I probably over-analyze everything. (at least that's what my wife says ) But, you're skipping over a couple of very important basic facts here:
1. Your location was approved for a "conventional" system. (ie: septic tank and field line) Millions of these have been installed over the last 100 or so years and MOST of them work, without issue, for years - even decades. BTW, my 1000 gallon septic tank has been in contiuous use for 20+ years without ANY problems, failures, backups, etc. All without ANY service, maintenance, or adding any "magic" bacteria. In fact, my septic tank has never been pumped. *NOTE: But, as I stated earlier, we don't abuse our septic system. We don't dump dirty mop water down the drain. We don't clean our plumbing fixtures with bleach. (yes, there are people who do this) We don't have a garbage disposal. (garbage goes in the garbage, not the septic tank) Etc, etc, etc.
2. The other thing, that you seem to be insistent on, is making a conventional system aerobic, by adding on after-market gizmos. I would be curious to know what your state sanitarian (that's the title here in LA) thinks about all that stuff. Septic systems, and thier various components, must undergo years of testing and trials, demonstrating that they actually work, before they are approved. IF these gadgets were so great, your state health department would have recommended them. But, they didn't. They issued you a permit for a conventional system.

You are anticipating all of these problems with a conventional septic tank, even before you have it installed. Just relax. It'll be OK. :thumbsup:

 

[Pettrix]

2. The other thing, that you seem to be insistent on, is making a conventional system aerobic, by adding on after-market gizmos. I would be curious to know what your state sanitarian (that's the title here in LA) thinks about all that stuff. Septic systems, and thier various components, must undergo years of testing and trials, demonstrating that they actually work, before they are approved. IF these gadgets were so great, your state health department would have recommended them. But, they didn't. They issued you a permit for a conventional system.

You are anticipating all of these problems with a conventional septic tank, even before you have it installed. Just relax. It'll be OK. :thumbsup:

As far "pumping" goes, it's like a car engine. Some people change their oil every 15,000 miles, sometimes longer, they claim that everything is fine but ONE DAY it will fail and fail catastrophically. That engine could have gone 200,000 miles with regular oil changes but since they changed it every 15,000 miles, that engine seized at 75,000 miles.

In regards to the county departments, they don't require annual check-ups on conventional systems. The reason why engineered systems require annual check-ups is because people fail to maintain them and when a mechanical element fails in an engineered system, the system shuts down completely. In a conventional system that has an aerator, if the aerator fails, the system still works. The system is not dependent on that aerator, the aerator is supplemental and helps but it can run without it. That is the beauty of it.

Let me ask you this. If on a conventional system that is gravity fed.
1 - If the aerator stops working, what will happen, does the system stop working?
2 -What harm will come from introducing air into the first chamber of a 2-chamber conventional system?

If you can show me how it will harm the system, I will reconsider my position.

Not everything in the septic industry and states codes is done for the betterment of people and septic systems. There is a lot of money $$$ involved in this industry and greed/corruption sometimes rules. Septic companies make the most money on their "engineered" aerobic systems and counties make a killing charging fees on engineered systems. It is a high dollar industry.

Here is an interesting read about the septic industry:

Excessive Engineering and Regulatory Overkill - The Septic System Owner's Manual (page 1)


"It may have started 15 years ago in California, when engineers began to convince health officials that the tried and tested gravity-fed septic system did not work (at least in a majority of cases). Where previously you could install a gravity-flow system, homeowners now had to install high-tech, expensive, electricity-powered "mound" systems. My septic system cost less than $3000 in 1972, and it has worked beautifully for 34 years now. My neighbor, maybe 500 feet away, with the same soil profile, recently had to install a $40,000 mound system. "

 

[Bigfoot62]

As far "pumping" goes, it's like a car engine. . .

No, my friend, it's nothing like a car engine. A septic tank only needs to be pumped if there is an excessive buildup of solids. IF you don't kill your bacteria, or overload the capacity of the tank, that won't happen.

In regards to the county departments, they don't require annual check-ups on conventional systems. The reason why engineered systems require annual check-ups is because people fail to maintain them and when a mechanical element fails in an engineered system, the system shuts down completely. In a conventional system that has an aerator, if the aerator fails, the system still works. The system is not dependent on that aerator, the aerator is supplemental and helps but it can run without it. That is the beauty of it.

True, true.
But, the real "beauty of it" is that a conventional system doesn't need anything to keep working properly.

Let me ask you this. If on a conventional system that is gravity fed.
1 - If the aerator stops working, what will happen, does the system stop working?
2 -What harm will come from introducing air into the first chamber of a 2-chamber conventional system?

1. No, it's still a conventional septic system - no aerator required.
2. I think it was Jim that said, you will be suspending solids that would normally settle to the bottom of the tank and be digested by anaerobic bacteria. Those suspended solids will find thier way into your leach field because a conventional tank is not designed to prevent that. It's not made for an aerator.

If you can show me how it will harm the system, I will reconsider my position.

See #2 above. Also, if local code allows a metal tank, an aerator will promote rapid oxidation, causing the tank to prematurely collapse. Years ago, there were some area manufacturers that built coated steel treatment systems. BAD idea.

Not everything in the septic industry and states codes is done for the betterment of people and septic systems. There is a lot of money $$$ involved . . .

Yep, that's why I believe that some installers try to sell aerobic sytems to people who only need a septic tank.

Here is an interesting read about the septic industry:
Excessive Engineering and Regulatory Overkill - The Septic System Owner's Manual (page 1)
"It may have started 15 years ago in California, when engineers began to convince health officials that the tried and tested gravity-fed septic system did not work (at least in a majority of cases). Where previously you could install a gravity-flow system, homeowners now had to install high-tech, expensive, electricity-powered "mound" systems. My septic system cost less than $3000 in 1972, and it has worked beautifully for 34 years now. My neighbor, maybe 500 feet away, with the same soil profile, recently had to install a $40,000 mound system. "

I highlighted (bold) the words in your above quote. That's what I've been saying.

I am researching septic systems for a home I would like to build in a rural area . . .

Hey, I've tried to directly answer your questions, based on my experience and proven industry standards.
If you're wanting to justify your opinion by winning this "argument," then congratulations - you win. I'm tired. I quit.

 

[plowking]

There has been some discussion about frequency of septic cleanings. I do septic tank cleanings in NH. I find that having well water,water softener discharge and customers on medications and the cold weather can slow down the efficeincy of the septic tank. The average around here is 2-4 years. A lot of newer houses have effluent filters,so the filters and/or the septic tanks need yearly cleaning. I have heard of tanks in warmer climates going a lot longer because the temperature stays higher year round in the tank. The tanks I do that go 15- 20 years between cleanings have deterioted and the outlet baffle is usually missing. Septage can turn sulfuric after it has been in tank for over five years. Sellers of houses that haven't been cleaned in a long time will sometimes call [ on advice of their agent]to have tank cleaned so they wont' get scolded by the septic inspector for the buyer. after seeing condition of system. plowking