In the 1990's David Kay, a home builder wanted to construct his own domestic waste system and after some research had decided that a dose loaded system using a siphon, not requiring power or pumps would ideally meet his needs. As siphons at the time were not readily available, he figured he could build his own using PVC pipes. He needed an engineer to certify his design and installation for local authority purposes and approached Colin Ashby a local Consulting Engineer.
At the same time, Colin had been struggling with the dilemma of providing clients with a low cost, simple and reliable on-site waste water disposal system which did not have the problems of a conventional septic tank, but without all the "bell and whistles" of a secondary treatment system- pumps, blowers, timers, float switches, alarms and all the electrically powered things that cost more money up front, burn electricity (money), are prone to break down and have high maintenance requirements.
David's dosing siphon system worked surprisingly well and met the need which Colin had foreseen. Although this system was developed initially for David's own use, Colin encouraged him to start manufacturing the siphons and Colin would design the siphon dosed primary system for other customers. David's initial system was to have a single chamber septic tank with an outlet biological filter, followed by the siphon mounted in a cattle trough with a lid. However at Colin's suggestion, the system was developed with the siphon commonly installed in a two chamber septic tank having a biological filter between the first and second chambers and the siphon mounted inside the second chamber at the outlet. By installing the unit in two chambers in a single septic tank it was easy for a drainlayer to pick it up with a hiab and simple to install. Between David and Colin, the idea of a distribution manifold has been developed downhill from the siphon to more evenly distribute effluent into a Low Pressure Effluent Distribution (LPED) disposal field. The unique manifold ensures that the bottom distribution line does not become overloaded or flooded as can occur with other LPED systems.
David and Colin have also developed an Excel spreadsheet to model the hydraulic design of the effluent field, and found the spreadsheet to be very accurate predicting flows within 5 to 10%. The spreadsheet design insures accurate and even distribution of effluent across the entire field for a variety of field configurations and over varied topography.
The first siphons were constructed from PVC pipe and PVC pipe components and did have their limitations. Initially they had a stall flow of about 30 litres per minute and an upper capacity of approximately 300 litres per minute. This design was copied by other people over the years who didn't fully understand the intricacies of the design and competing siphons today don't always work as well as even David's original design.
David however has continued to apply his experience and intuitive understanding of natural fluid flow and the latest iteration, the Super Siphon, is so good that it does not stall at any flow range (high or low) even if the flow is completely stopped and can be field modified for a range of drawdown distances. The design is so innovative that it has been patented. To facilitate the design the siphon has been constructed using a rotomoulding process and is made of polyethylene plastic which is tough, long lasting, non-corrosive and much more environmentally friendly than PVC.
David and Colin formed Vortech Ltd, a company to manufacture and ensure the quality and reliability of the siphon which they have developed. With the great assembly and distribution team at Autoflow Ltd we think we offer the best siphon on the market today. Through Vortech Ltd. David and Colin intend developing other low energy, environmentally friendly products for the benefit of mankind such as the self cleaning water filter.