We fell in love with our hilly land, but before we bought it, we were advised to have a soil evaluation report a.k.a. perk test done to see if we would be able to build an at-grade septic system instead of a mound system for our future (now not so future) house.
The Wisconsin At-Grade system has been approved since 1982 on sites where soils are too deep to require a mound, but too shallow to install a below grade soil absorption system.
At-grade systems are less expensive than a mound system because there is no need for costly C33 sand. They do less construction damage than in-ground soil absorption systems because because there is less excavation required in the absorption area.
We felt lucky to be one of the few sites in our township that met the qualifications.
The county sanitarian told us that the only other option was an outdoor privy permit for an outdoor toilet. He said that to legally spend the night in any building on our land we need a septic system or a permitted privy. Legally this privy could not be an old fashioned outhouse or a modern composting toilet. The official wisdom in our county is that human waste has to go into a septic system or a buried tank – both of which must be periodically pumped and hauled who knows where. Collecting everyone’s “septage” into one spot to deal with it, when people with enough space could be composting it instead seems like overkill.
According to the Wisconsin Department of Commerce, a certified pumper (septage servicing operator) can dispose of septage from the tank at a municipal waste water treatment plant or through land application if allowed by local codes and done according to septage disposal regulations. Many tanks need to be pumped every 2-3 years.
Several factors determine tank pumping frequency:
- Number of people living in the home
- Water usage
- Garbage disposal or whirlpool tub
At present while camping out, we have been doing just fine with a Luggable Loo. This system is remarkably easy to maintain and odor free. I see from looking at homes on the Tiny House website that many Tiny House home owners use a basic lugable loo for a toilet, and have no gripes. If any of you have found you can live with luggable loo/or composting toilet and gray water system for general washing purposes, more power to you. This is without a doubt a more ecological way to go, and I’d love to hear about it.
But we are going with the official system to keep our local inspectors happy. (We are already going to be asking a lot of our inspectors with whole tree timbers, strawbale walls and sod roof.)
Then to keep ourselves happy, we will add a composting toilet in one of our two bathrooms in the house, which will mean very little use of this septic system we are now in the middle of installing. We won’t have a garbage disposal or whirlpool.
Here’s what we have learned about the care and feeding of our septic system to keep it as green as possible.
There are two layers of solids that form in the septic tank: one that settles to the bottom and a scum layer that floats on top. Only the liquid in between these two layers is pumped to the drainfield.
To minimize the amount of solids:
- Don’t flush cigarettes, diapers, feminine hygiene products, paper toweling or facial tissue. They can contribute to the scum or sludge layers
- A garbage disposal can contribute considerably to the sludge build up
- Don’t put grease or oils down the drain from cooking, or skin lotions. They increase the scum layer.
- Use liquid detergents instead of powdered detergents because powdered detergents have fillers that add to the sludge layer.
- Use toilet tissue that breaks down rapidly. Test by placing a tissue sample (preferably unused) in a jar of water. Cover the jar and shake rapidly. The tissue should fall apart easily when shaken.
- Install a filter on the washing machine water discharge line to trap lint.
- A biggie that we want to make sure gets done right now is to have an effluent filter installed on the outlet of the septic tank to help prevent solids from flowing into the drainfield.
- Keep hazardous materials OUT, like herbicides, insecticides, paint thinners, solvents, excess medications and cleaning products including bleach and drain cleaners (automatic toilet cleaning dispensers are frowned on).
- It’s not necessary to use additives like septic system starters.
In this way we will minimize the amount of our “septage” being hauled hither and yon while staying out of conflict with local requirements.