Wisconsin Mound system?
Muddytyres
| Posted in General Questions on
I’m considering purchasing a house that needs a lot of work to make it Green. It has a wisconsin mound system septic which we really don’t see around here and I know very little about. I’m in zone 5. It would have been installed in the 1970’s. Could someone tell me more about this system or give me a source of reliable information?
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Replies
Hi Sara -
there does not seem to be any info on this topic on GBA to date. The only resource I could find with an internet search is this one: https://www.env.nm.gov/wp-content/uploads/2017/08/WisconsinMoundManual-1.pdf.
You probably need to find a local expert or see if anyone in your Agriculture Extension service has experience, possibly a soils scientist.
Peter
Thanks. It's interesting that I'm not finding much info.
Mounded septic systems are in wide use throughout the country. This is the first I've heard of them being called a "Wisconsin" mound. Probably only called that in Wisconsin. The manual that Peter found describes what I've typically seen as a mounded system, and it's a good primer on their design. Being published in 2000, it's pretty current. Your state DEP and/or agricultural extensions will probably have detailed regulations for their design in your state.
Mounded systems are used when the characteristics of the local site or soils are not conducive to a traditional gravity system. They work just fine, but do have the added complexity of the pumps and controls to deal with.
Maintenance generally consists of pumping the tanks and occasionally replacing the dosing pump and controls. Any septic system installed in the 1970's may be approaching the end of its useful life, and a mound system is no different. It is important to know how many people are using the system vs. how many it was designed for. A 4 BR system might work fine for a single user but be nearly useless for 4 people. Have it inspected by a local septic company that has knowledge of mounded systems and prepare for some expensive repairs.
Recently on the Canadian show Holmes and Holmes they used a mounded septic system because there wasn't enough room on the site for a traditional septic field. The system involved using an extra tank for further filtration of the waste water.
https://www.ecoflobiofilter.com/waste-water-septic-tanks/green-technology
https://www.ecoflobiofilter.com/main-navigation/discover-ecoflo/tertiary-treatment.aspx
Basically at the front of the property they built a rectangular stone retaining wall and placed the septic system inside and then covered it so that it looked like a raised garden.