Radial Flow Splitter

This unique and patented device is a new concept for effluent distribution for your septic tank.

Gravity fed effluent distribution has been an underdeveloped area for many years with many problems and complaints as a result.

The invention of the Radial Flow Splitter was followed by extensive research and testing in collaboration with IT Sligo. A thesis was dedicated to the subject: ‘Review of the Effectiveness of Gravity Effluent Distribution Devices Used in Domestic Wastewater Treatment Systems’..

Improved Effluent Distribution

  • Even distribution via up to 12 outlets per unit, unaffected by off-level installation or soil settlement.
  • Improved treatment, reduced risk to ponding, pollution and odours.
  • For use of standard 1.5” pipes on the outlets.
  • No clogging as with perforated 4” percolation pipes.
  • Designed and tested for dealing with dirty water and bio-film.
  • No moving parts and easy to inspect.
  • The system makes it easy for you to multiply discharge points by interconnecting a few splitters, e.g. for larger areas.
  • The outlet pipes do not require exact sloping as with perforated pipes.
  • Installation on slopes is now a lot easier also. Pipes can run very shallow or even above the surface, as long as the effluent exits at the set depth. This enables alternative layout options e.g. allocating different areas on the site with the most favorable conditions.

Also important to know: The effluent coming from the tank can either be driven by gravity or by a pump into the flow splitter. Any percolation area however requires constant as possible conditions for treatment to be effective. A constant drip therefor is preferable to i.e. an intermittent flush coming directly from a large pump. To improve this is to use simply an additional tank, pond or otherwise, to attenuate the flow coming directly from a pump before it enters the percolation area.


Two different RIBBIT Radial FLOW splitter mOdels
Two different RIBBIT radial flow splitter models. Notice the different arrays - 4 inch & 1.5 inch inlets.

Build for on-site wastewater treatment systems with a septic treatment tank. Designed to distribute the effluent evenly into a common percolation area, raised bed, willow system or vertical-flow reed bed. Uniform percolation can now be achieved building a simple system with dozens of discharge points. No more ponding, pooling, clogging or blocking.

Two different RIBBIT Radial FLOW splitter mOdels


Improved distribution of septic tanbk effluent with RIBBIT Radial Flow Splitter

Wastewater Distribution Specifications

  • Housing: 12” PVC riser. Max. height 200 mm.
  • Outlets: Depending on model
    • 1.5” female connectors (4x or 12x), radially positioned.
    • 4” male connectors (4x), radially positioned.
      Number can be reduced by combining outlets internally. Required blank-off caps are provided.
  • Inlet: Depending on model
    • 1.5” female connector or
    • 4” male connector.
  • Head loss: Between inlet and outlet: minimal 72 mm. Internal components are easy removable for inspection.
  • Materials: Plastic (PVC, HDPE, PETG and PLA) and ceramic.
  • Weight: Approx. 5 kg.
  • Compliance: Compliant with EN12566 for use in onsite waste water treatment systems, depending on application
  • Flow rates:
    • 20 ltr./min. maximum accuracy.
    • 20 - 40 ltr./min. effluent will also flow through inbuilt ‘secondary baffle’
    • above 40 ltr./min. inundation. Internal splitter will overflow with surplus of effluent flowing directly into outlet pipes.

Radial Flow Splitter Insert

(to be placed inside your existing distribution box)

RIBBIT Radial Flow Splitter for use with perforated pipes, for improved effluent distribution
This unit is specifically designed for remedial applications where poor distribution is causing issues. It can be fitted within a few minutes. It is compatible with a standard 14” square D-box with 4 outlets but other sizes and configurations are available upon request.

Starting at € 89 excl. VAT

12 way Radial Flow Splitters

(12 x 40mm outlet for septic tank, willow beds etc.)

12 way RIBBIT Radial Flow Splitter for improved distribution of effluent
This unit has 12 outlets to connect to standard 1.5” pipes.
Even when installed 1” off-level one can expect the differences in flow to be within 20% accurate.

Starting at € 149 excl. VAT

4 way Radial Flow Splitters

(4 x 40mm outlet - primary radial flow splitter for willow beds etc.)

4 way RIBBIT Radial Flow Splitter for improved distribution of effluent
Almost identical to the 12 Way unit with slightly different internals. You choose 4 outlets only and blank off 8. This makes installation easier if a larger number of outlets is needed and use this as a primary splitter and attach 4 secondary splitters. Also available as a 2-way or 3-way splitter. The picture features an additional conical baffle. This may be needed if effluent is pumped in directly and at a (too) high pressure. .

4 way 110mm Radial Flow Splitter

(4 x 110mm outlet for common percolation areas)

RIBBIT Radial Flow Splitter for use with perforated pipes, for improved effluent distribution
This unit is based upon same principle as 4- and 12-way systems but is compatible with more conventional percolation methods whereby 4” perforated pipes are fitted and located inside elongated stone-filled trenches. Ideal for those who feel they have good reasons to stick to this traditional set-up but want the most accurate distribution over 4 trenches.