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WLS-042 Experimental and Alternative Onsite Wastewater Treatment Systems (OWTS)

Appendix A of the Onsite Wastewater Treatment Systems (OWTS) Manual with lists of approved experimental and alternative OWTS.

Version: 09/15/2019

Appendix A

OWTS Systems

  1. Approved Experimental OWTS
    1. Bottomless Sand Filters
    2. Gravel less Pressurized Dispersal Channel (GPDC)
  2. Approved Alternative OWTS
    1. Wisconsin Mound System
      1. An above ground system built with a gravel bed and sand area
      2. Pressure distribution
      3. Sites with shallow soils
    2. At Grade System
      1. An above ground system built with gravel
      2. Pressure distribution
      3. Sites with shallow soils
    3. Drip System
      1. Shallow subsurface dispersal
      2. Time dosing, pressure distribution and flexible tubing
      3. Sites with shallow soils; steep slopes (greater than 30 percent variance)
    4. Shallow Trench Pressure Distribution (STPD)
      1. Pressurized trench system for sites with shallow top soils over slowly permeable or fractured rock
      2. On slopes up to 30 percent
    5. Shallow in Ground (SIG)
      1. Utilize shallow depth trenches and pressure distribution
      2. Minimum if 24 inches of soil below the trench bottom

Pretreatment Units


  1. Aqua Filter
  2. Pura System SBR (aeration system), Models PS1-4 through PS1-8 and PS1-9 through PS-14
  3. EZ-treat (Recirculating Synthetic Filter)
  4. Aqua Klear (Air diffuser)


  1. Peat Moss Systems
  2. Recirculating Sand Filter
  3. Single Pass Sand Filter
  4. Advantex Units (filter fabric)
  5. Clearstream
  6. Bio-Microbics Fast
  7. Hoot Aerobic
  8. Microseptic Enviroserver
  9. Multiflo
  10. Norweco Singulair
  11. Norweco Biokinetic Singulair
  12. Nayadic
  13. Peat filter
  14. Southern Aerobic
  15. Whitewater Aerobic

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