GeoMat Leaching System

Over 50,000 feet of GeoMat installed in Wisconsin since 2017

GeoMat is approved for the following applications in Wisconsin

  • Conventional gravity systems 

  • Conventional dosing systems 

  • Conventional pressurized systems

  • Regular mound systems

  • Split-bed mound systems


GeoMat Wisconsin Component Manuals

  • GeoMat Inground Component Manual (Click to download)

  • GeoMat Mound Component Manual: Regular Mound and Slit-bed Mound (Click to download)

  • GeoMat inground and mound pressurized systems do not require a gravity effluent filter;                   they do require installation of a pressure filter after the pump.


Load rate for conventional systems

  • The load rate directly under the mat receives 2.0 gallons per day per square foot

  • The basal area receives Column 2 in Table 383.44-2

Load rate in mound systems

  • The area directly under the mat receives 2.0 gallons per day per square foot

  • The basal area receives Column 1 in Table 383.44-2

Split-bed Mounds

How does GeoMat work?


  • GeoMat is comprised of fused, entangled plastic wrapped in fabric on top and bottom.

  • The thin 1" profile maximizes contact with the soil - which enhances oxygen transfer.

  • Together, the fabric and the filament pull the water across the entire surface of the mat.

  • 12” of sand is placed under the mat; providing max treatment of wastewater.


  • GeoMat is 39” wide x 1" high

  • It comes in 100' rolls; a roll is 36 x 36 x 42

  • A roll weighs 70 lbs.

  • A roll easily fits in a pickup (right)


GeoMat utilizes shallow burial depth and even dispersal of effluent to maximize oxygen transfer​

  • GeoMat shallow burial depth (Ideal 12" - Max 42") increases the flow of oxygen to the leach field.

  • The shape and the membrane together draw water away from the point of application,                        across the entire surface of the mat. 

  • Water moves quickly down through the sand beneath the GeoMat,                                                          resulting in different levels of the sand being saturated only briefly, if at all. 

  • As such, the oxygen transfer mechanism is air being pulled behind the dose                                            of water as the wetting front progresses.

  • Since air is being drawn behind the wetting front, oxygen is being supplied                                              to the microbial community in the sand treatment medium.


GeoMat relies on oxygen in the air to create an aerobic environment in the leachfield  

  • Air is 21% oxygen, which means it is 21,000 times greater than the amount of oxygen in water.

  • The higher level of oxygen available in the sand medium is precisely why GeoMat works                        at higher performance levels than ATUs.

  • As a result, GeoMat consistently achieves treatment objectives and is more robust than an ATU.


​​GeoMat brings effluent into contact with as much surface area as possible

  • This is achieved by REDUCING the storage volume so every dose comes                                              into contact with more leaching system surface area. 

  • When effluent infiltrates the sand or soil, it pulls down air from above; provided                                        the top of the system is permeable (allowing liquids or gas to pass through it). 

GeoMat 2.0 gpd/sq.ft. load rate and hydraulic capacity were proven in stringent NSF testing

  • When a proprietary system is tested by ANSI/NSF, or other similar testing authorities,                            the leaching system is hydraulically loaded at the design loading rate every day.    ​

  • The design loading rate used to load the leaching system includes a peak flow,                                        which includes a safety factor typically between 1.5 to 2 times. 

  • In addition, the ANSI/NSF regime requires a high flow stress test be performed.

  • The loading rate applied under NSF testing protocol should never happen in the real world.

  • If the system passes ANSI/NSF testing, it is clearly capable of handling the daily              design load and any reasonable factor above and beyond what has already been                     

      used to establish state regulated design flow values.

How much does GeoMat cost?


1 Roll              $13.75                    $1375.00           

3 Rolls            $13.25                    $1325.00

5 Rolls            $12.75                    $1275.00

How much does GeoMat save?

Example 1:  4-bedroom mound instaled in 2018 in Monroe county

























Example 3:  GeoMat only requires 37" insitu soil in inground installations
  • Dosing systems use 2" Sch.40 pipe with 1/2" orifices drilled at 4 and 8 o:clock

  • Orifices are spaced at 12" intervals; they do not require orifice shields

  • Unlike pressurized systems, dosing systems are approved by counties

  • The quality of a pressurized system at substantially less cost


Example 4: "The bad news is time flies. The good news is you're the pilot."

Everyone values their time differently, so we won't put a dollar figure on it.

We will say the first thing everyone mentions is how fast and easy the job went.  

GeoMat Load Rate Calculations
Based on WI SPS Chapter 383 Table 2

Example 2:  GeoMat vs. EZflow or Stone (.4 Load Rate - 4% Slope - 21" Sand​

Installing GeoMat

Put down 12" of C33 sand, roll out GeoMat, insert laterals, cover with natural fill. THAT'S IT!

Below: Inground pressure system installed by Brian Gundy Septic Systems in Oneida County

Below: 4-bedroom dosing system installed by Brandenburg

Plumbing & Heating, Wausau in 2018

GeoMat is a product of Geomatrix Systems Inc. located in Old Saybrook, CT

  • Dave and Elizabeth Potts founded Geomatrix Systems.

  • Dave 25+ years of experience working with soil and water treatment systems. 

  • He is responsible for GeoMat as well as many other products. 

  • His credentials include authoring peer reviewed articles and studies related to septic systems. 

GeoMat History

  • ​The first experimental GeoMat system was installed in Connecticut in 2002 (it is operating today)

  • The first GeoMat approval was granted in Connecticut in 2006

  • Since 2006, GeoMat has been approved in 17 states with no reported failures