Grey water hugelkultur

Hi, new here like many. Here is my situation, sloped site in central NM, semi arid 7500ft, dry,13"-15" counting snowmelt. Building an off grid all solar house on a south facing slope from recyclings of a closed down saw mill. This has resulted in a LOT of scrap fir and pine as well as the fire safety thinning of pinyon and Juniper. The fill required for the house resulted in a pit 25X60X5 down hill from the home site. So, the pit which is in a small watershed is now filled with the aforementioned unuseable logs and cutoffs. during the monsoons it does fill with rainwater.
My plan is to pipe all household grey water to this ( high clay site), cover the pit with about 40 or more yards of composted manure and a bit of soil, ( we have no top soil to speak of here) and fence it off as a future garden site ( mule deer/elk/rabbits/bears etc.)
Has anyone experience with using grey water, and such a deep pit? Should I try to distribute the greywater near the surface? Does that matter?

I'm thinking the first pit could be filled with reeds, papyrus, or other marsh type grasses to clean the water. Then overflowing into a secondary pit with lotuses or other plants that grow in your area and maybe some fish. That water would then be good to use on all of you garden.

Michael S. New wrote:a pit 25X60X5 down hill from the home site. So, the pit which is in a small watershed is now filled with the aforementioned unuseable logs and cutoffs. during the monsoons it does fill with rainwater.
My plan is to pipe all household grey water to this ( high clay site), cover the pit with about 40 or more yards of composted manure and a bit of soil, ( we have no top soil to speak of here) and fence it off as a future garden site ( mule deer/elk/rabbits/bears etc.)
Has anyone experience with using grey water, and such a deep pit? Should I try to distribute the greywater near the surface? Does that matter?

No such experience. But from your description, I'm curious about the small watershed. Try to imagine it filled with a garden, and then having a monsoon rain. What would that look like? What would it look like with a larger than average (say a 10 year or 50 year) rain event? The concern is that you will create a big garden slurry/slump in the wrong situation. If this is not a concern, it sounds like you have a great site for a future garden.

Considering that you mention snow, there is considerations of the ground freezing. It is imperative that the greywater outlet be below the frost line. If you are high up in NM the frost can be deep.

It sounds like the wood will turn into a nice hugul once it becomes buried. I don't think you need to go too deep, just below the frost line and root zone of your nearby plants.

If you are gardening in the greywater zone, there is consideration of ensuring that the greywater drain is not blocked or clogged by roots or soil/ or a bacterial anaerobic slime seal. Study up on creating a good outlet doing this job only once! I would suggest that it dumps into a worm bin, which will eat the slime and create a biofilter for the waste, but this is not necessary so long as you build a good outlet system.

Sounds like there is a lot of wood in there. kind of too bad, because if it fills with water it might be a great place to have a pond system, with hugul beds extending out of it on the sides as chinampas.