Cost of Septic System

[Radiopeg]

Now that we are considering purchasing a lot to play on while we wait for our mainland house to sell, I am starting to research the cost of making the lot ready to build. So my question is, what does a cesspool system cost VS septic? We intend to be Fern Acres. Are people generally putting in cesspools where it is permitted? I find it hard to believe it is still legal anywhere.
I stuck this on the very helpful septic link, hoping to troll for cesspool info.

[Peter Epperson]

I believe that the law hasn't changed and it is still legal to have a cesspool if you have over 1 acre and are more than 1000 ft. from the ocean. Septic systems are appropriate when your sewage can compromise the water table. Fern Acres is well over 1000 ft. elevation and it's very unlikely that any biological material that you dump into a cesspool there will ever be a threat to the water table. Besides that, a septic system will cost you 3 or 4 times more than a cesspool and it needs to be maintained. I can't imagine any reason why you would need a septic system in Fern Acres. I think that the health department agrees. They were very reluctant to make the change to septics in the first place but were required to by the EPA. I think that they have stalled requiring septics everywhere because they realize that in many situations they are unnecessary.

[hotinhawaii]

"Fern Acres is well over 1000 ft. elevation and it's very unlikely that any biological material that you dump into a cesspool there will ever be a threat to the water table."

The elevation has nothing to do with the water table. Raw sewage could easily make it's way into the water table in Fern Acres as the water table could be very close to the surface. In the long run, septic systems are much better for everyone.

If a septic system isn't required but you still want to be environmentally friendly and save money at the same time, consider a seepage pit. It is basically a normal cesspool but with a holding tank located upstream in the waste discharge. This tank will pretreat the waste before it goes into the cesspool.

[hotinhawaii]

As an aside, I was once camp director at a camp where the waste from cesspools eventually began to find it's way into the camp's water table and up through the well. After becoming violently ill and forty other campers along with me, the health dept. shut down the camp. It took a long time for that cesspool to fail, but fail it did.

[MarkP]

My parents live in central NY at an elevation of about 850 feet. They are now on county water but for more than 25 years they relied on a well. The well was only 85 feet deep. Their neighbor 2 lots down had to drill more than 400 ft to get "good" water but had hit water at only 100' or so. This is normal in many parts of the world where the water table (the line where the water stops trickling directly down and starts spreading out sideways) follows the contour of the land. This is due to millions of years of weathering and sedimentation during which impermeable layers develop. Hawaii in general and the big island in particular is pretty young for these processes to have occurred and in general all the islands are giant piles of fractured rubble with intermittent impermeable layers of pahoehoe. While I know that the board of water supply for Honolulu does find pockets of water well above sea level called perched water, they have huge advantages as far as economy of scale goes to find and develop these sources. The rest of us must count on drilling down almost to sea level which is where both rain and sewage goes. Depending on how porous the rock is and how high above sea level you are it can take decades for the water to trickle down, after which you could probably drink the sewage without harm. If however you are near sea level and the rock is porous it can get there very quickly. This definitely can and does happen here in Hawaii as it does elsewhere and it means that you can be swimming in tainted water when you go to the beach or even a well can be tainted. The thing about Hawaii is that the ground is generally so porous. Every slab of pahoehoe has an edge or crack in it somewhere so pretty soon the water goes straight down.

So how is a cesspool different than a septic system? A cesspool is a deep hole in the ground that makes no effort to spread the sewage out over a wide area. The design inherently speeds the sewage on its way down. A septic system is a very shallow hole in the ground that is required by code to spread the sewage out over an area proportional to the expected flow and to deliver the sewage to the top couple of feet of soil where there is oxygen present and where there is tremendous surface area in the surrounding sand and gravel backfill on which aerobic bacteria can live and consume the pollutants. The septic tank also has features to capture solids before the liquid gets to the leach field, in contrast to a cesspool where the solids are free to migrate into the soil. This is not so much to protect the environment. Whether it is water or solids, if it has essence of poo in it it is equally bad and in fact the water is more mobile. The reason the septic tank captures the solids is that the leach field is intentionally designed with very small gravel to get very high surface area. For purely mechanical reasons the solids, if they get through, will clog up the leach field. That is the reason that septic tanks must be pumped regularly. Cesspools sometimes also need to be pumped but by the time that happens you are screwed because it means that the little cracks are all full of solids and the water can't escape. If you let the septic tank go that far you would be equally screwed, but at least with the septic tank, periodic preventive pumping can maintain the porosity of the leach field indefinitely by preventing solids from ever getting to the leach field.

[Radiopeg]

quote:

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Originally posted by Peter Epperson

a septic system will cost you 3 or 4 times more than a cesspool and it needs to be maintained....I think that they have stalled requiring septics everywhere because they realize that in many situations they are unnecessary.

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Thanks, Peter, so much for that info.

Life goes on, with you or without you.

[ericlp]

Another option to consider and I guess you can get plans drawing up with out a cess pool / septic?

That option is a composting toilet by Sunmar. I guess they are now permitted? Well, you could buy your composting toilet from anyone just sunmar is an example.

Then you just collect your grey water for use to water your garden. You know, your shower/sink/washer water ...

I'm pretty sure you could build your own composting toilet, tho... a bit more work would be considerably cheaper then plumbing in a septic / conventional toilet.

[MarkP]

I know we are talking several thousand dolars, which is nothing to sneeze at, but I advocate putting in the cesspool or septic system, then directing as much of my waste as possible elsewhere. No need to tell the county anything about alternative methods of disposal, and you will always have a regular toilet for those squeamish individuals who don't like to use a composting toilet. Finally, resail value will be better with the conventional system installed. I personally feel somewhat bad about using only a cesspool even where it is allowed, because I know they can cause problems with the ground water. Well, I will install one to satisfy the county but I will use it as little as possible.

[David M]

Just curious, just how would such a set up affect resale?

David

Ninole Resident

[MarkP]

I assume that meeting peoples expectations as far as having a normal septic system would put potential buyers at ease. I have often heard disparaging things said about composting toilets, that they smell, etc. I don't think it has to be that way but it is not me that needs convincing.