Underground house plan

Hello fellow off grid lunatics,
I'm new here but have been doing a lot of research into Off grid lifestyle.I have come up with a few sets of designs and would love some input.I am sure there are things I've overlooked
and would appreciate any help I can get.
I have come to the conclusion that my roofing system will have to be above grade at least until I can properly figure out how to waterproof the dwelling then I can use the dirt from th pond i'll dig to cover the top of the house.I am wondering how big a deal waterseepage into the structure is? If I build the roof above grade I should be able to Cantalever out a couple of feet and stop imediate runoff.
I found the attachment bar at the bottom so illl upload my diagram for my plumbing and septic system.Give it a look and any suggestions would be welcome.
I'll be back l8tr,

Looks like you are mixing grey and blackwater and using a standard leach field? That is very wasteful, especially with only a 550 gallon cistern.

I didn't post the septic drawing yet it sends all waste water created out to growing plot. Its underground so suggestions would be helpful.
Also doing it myself limited space and finances.I felt this would be the most efficient way to get the plumbing installed.Perhaps line installed taking grey water Where?

Since this thread is in the Earthship forum, I sort of feel like you are aiming toward an Earthship-style plumbing system.

If that is the case, this plan is all wrong. Your cistern is tiny if you are using rainwater harvesting. You're throwing the bulk of your perfectly good greywater into a septic system and therefore making it unhealthy blackwater. You are flushing your toilet with potable water. You're growing edible plants over a blackwater leach field. You have to light a fire to make hot water, then you have no control over the temperature....

My suggestion: Don't reinvent the wheel. Plans for Earthship plumbing systems are not hard to come by. Earthship Biotecture will even sell you a water module which brings together the bulk of the filters and pumps necessary. The system should:

1) Use unfiltered rainwater for your sinks, showers and bath. (or use filtered potable if you have children who tend to drink their bathwater!)
2) Filter rainwater for potable to a seperate spigot.
3) Take all water from the sinks to a greywater botanical cell in which you can grow edible plants.
4) Collect treated greywater from the botanical cell to flush the toilet.
5) ONLY send water from the toilet to the septic, which can now be much, much smaller.
6) Send effluent from the septic to a seperate botanical cells with NO edible plants near the surface (it is okay to grow edible tree and vine plants, but you don't want things in the ground because if the septic overflows you will be eating the shit of everyone who uses your toilet)
7) Don't use a leach field. Leach fields are effectively putting shit in your groundwater.
Heat water primarily using a solar collector system. (using an absorber coil from a stove is okay if you must use a stove often enough for the heat input to be substantial)

Alternatively, you can use a composting toilet and thus not need a blackwater system at all. This simplifies everything but many people don't like using composting toilets.
Also note that this system would still work correctly even if all your botanical cells are outside. It is a matter of increasing the plumbing length.

: I think you are right about the gray water it wouldn't be that much trouble to run the sink and and shower to a seperate system, but what about the soap? We are going to try and take a stab at making our own but, it takes weeks before they can be used and still contain ash based lye.We'll probable use store bought for a while as well as laundry detergent to clean our clothes.
Thats a lot of extra steps settin up two diferent supply systems for water.
I was planning on digging a well and filling a 2 x 350 gallon water tanks with a solar powered 12v pump, and gravity feed system to the home.
I would only need to run it when the top 350 gallon tank runs low.
It will then pass through a 12V UV purification system only turned on as needed I will be burning the Highly efficient gasifying wood stove that will use only 16% the wood of as conventional wood stove and attaching it to an antique wood burning cook stove I have just purchased. It will cook our food and the remaining energy will be used to heat the water.
The avg. temp. should remain around 50-55* most of the time, but we will have to cook every day anyway.
As far as collecting Rain water, I hadn't even factored that in. We are building underground and most people do that through a gutter system.
We are building into the side of a hill with a southern facing exposure, to take advantage of all the natural lighting we can get.
The plan is to use LED lamps that run on rechargeable batteries for the most part, and only use battery banks when we have to. I have also been looking into using side illuminating fiber optic rods as an option for supplimental light at night.
One High output LED hooked up properly can light up many seperate rods, placing a mirror at the end of it doubles the intensity of the rod.
The property we are looking into purchasing right now has a natural spring fed year round creek on it, we are also looking into a water turbine system to suppliment the solar.
there have to be trade offs somewhere,No system is perfect but this is far more Eco-Friendly than I'm living now .
Thanks for the input I enjoy the chat.