WaterFlow Resources

Warranties, compliance and our frequently asked questions.

WaterFlow Documents


Waterflow NZ Ltd warrants that the NaturalFlow system will be free from defects in material and workmanship for the following periods of time from the date of installation as set out in the following conditions:

  • Roto-Moulded tanks and components 15 years
  • Filter media 15 years
  • Dosing float and/or pumps 2 years
  • Waterflow NZ Ltd will at its discretion replace or repair such components that prove to be faulty with the same or equivalent part at no charge.
  • Warranty of operation only covers the performance of the NaturalFlow systems as connected to the effluent inflow for which they are designed, and also installed to the criteria as set out in the relative installation instructions and procedures.


Warranty excludes defects due to:

  • Failure to use the system in accordance with owners manual.
  • A force majeure event outside the reasonable control of WaterFlow NZ Ltd as such but (not limited to) earthquake, fire, flood soil subsidence ground water table variations or plumbing fault.
  • Modifications to surrounding landscape after installation.
  • The actions of a third party.
  • The system required to bear loads (either hydraulic or biological) greater than that for which it was designed.
  • Any modifications or repairs undertaken without the consent of WaterFlow NZ Ltd.



The NaturalFlow System complies with all the following standards, as set out in the NaturalFlow Compliance Requirements document.

The NZ Building Code

Section of AS/NZS 1546.1:2008 and Section of AS/NZS 1547:2000 state that tanks constructed to these Standards will meet the requirements of the code for Clauses B1 and B2, structure and durability
Clauses G13.3.4 relating to on-site treatment and disposal systems and G14.3.1 and 14.3.2 relating to the control of foul water as an industrial waste, are also covered in engineers Producer Statement – PS2 – Design Review

AS/NZS Standards

Compliance with the relevant sections of Section 9 of AS/NZS 1546.1:2008
Compliance with the relevant sections of Parts 2 and 4 of AS/NZS 1547:2000


WaterFlow NZ Ltd. FAQs
How Does Your System Work?

Waterflow NZ Ltd, after following the history of sewage treatment, recognized the benefits of treating the low volume, high toxicity black water (from toilets and kitchen sink) separately from the high volume, low toxicity grey water (from baths, showers, dishwashers, laundry etc).
Separated at their source, these waters receive selective treatment in view of appropriate disposal into the environment. The black water passes into the WORMORATOR® which is an enclosed Eco-System, simulating the forest floor, where the solids are separated from the liquid and treated through Vermiculture and various natural processes and filter media’s. Vermiculture processes, as shown through
extensive trialling, reduce the solids by up to 95% which is unmatched by any other type of system meaning virtually no ‘pumpouts’ or hassle of getting rid of this waste. Treatment of the large volume grey water is through a series of natural filtration processes. This water is then combined with black water for final disposal into the soil as per council regulations. The NaturalFlow system also welcomes the use of a Waste Master in the kitchen sink, an added bonus if you so desire!!


Systems are normally held in stock and ready for dispatch from the Waterflow yard.

Does it require Power?

No, the NaturalFlow system uses completely natural aeration processes and does not require an external power source in any of the aeration process – in fact where you have a sloping section you do not require any power whatsoever!

Can the Grey Water be reused?

Yes, this water can then be used for surface or sub-surface irrigation eg; watering trees, hedges, plantings, orchards etc.

Does it require a Soakage Field?

Yes, you will need either driplines, or a soakage field or a combination of both depending on which model or series you choose. These options also depend on the council requirements for the area and the soil types etc on the site.

Is it accepted by Councils?

In most cases an Onsite Disposal System will be a permitted activity and all the Council will require is a site assessment, which will need to be done by a suitably qualified person (this is often incorporated in a Geotech report on the site relating to the building project). This can also be done by a accredited NaturalFlow installer.

What are the Maintenance Requirements?


Maintenance is set out in a homeowner’s manual. The home owner can be trained to manage their system as it is very straightforward and mainly involves only simple visual checks on the system. Waterflow would recommend a yearly visit from an installer and some council’s are now starting to insist on this.

Download the operation manual here:

Home Owners Care Guide

How do I Protect the Worm Colony?

You can help maintain an effective wastewater system on your site, by ensuring no toxic or high chlorine chemicals are put down the Kitchen sink or toilets. A home owner’s guide will be provided with your new NaturalFlow system.

Does Antibiotics or sickness have any effect on the worm colony?

Antibiotics when used in the home through periods of sickness have proven to have no adverse effects on the Worm Colony.

Does temperature affect the Worm Colony?

The Tiger Worms are breed in Cromwell, Central Otago, where they have extreme temperatures ranging between -7° to 38°c. They are well adapted for all of New Zealand’s harshest conditions.

What if the Worms die?

This would be very unusual and would have to be a result of prolonged flooding or toxic chemicals, but this will show up very quickly, through visual checks, and the Wormorator can easily be reseeded with Tiger Worms.

Can I install it myself?

The Natural Flow system, as with all sewage systems, must be installed by a Registered Drainlayer or preferably by an accredited Natural Flow installer.

Can I use my own Drain Layer?

Yes, but the advantage of using an accredited installer is they will provide technical support before, during and after installation.

What is the Difference between an Advanced Primary and a Secondary System?

It relates to the treatment level or purification of the wastewater, with Secondary being more pure than the Advanced Primary level.

What is the minimum Distance allowed for a system from a building?

Anything greater than 3 meters from the building, under permitted activity.

What shouldn't you flush down your toilet?


Dental floss, feminine hygiene products, diapers, cotton swabs, cigarette butts, coffee grounds, cat litter and other kitchen and bathroom items that can clog and potentially damage septic system components if they become trapped.

Flushing household chemicals, gasoline, oil, pesticides, antifreeze and paint can also stress or destroy the biological treatment taking place in the system or might contaminate surface or ground waters.

How close can I discharge to a waterway/building/boundary etc?



We’re in 6,000+ backyards around Aotearoa New Zealand

At WaterFlow we work across the country recommending and installing smarter wastewater and sewage systems, for a cleaner New Zealand.

Whether it’s upgrading a water tank or installing a new water system, we always offer bespoke solutions designed to fit your environment and lifestyle. Take a look at our recent projects to be inspired.

Passive Solar Home

Our clients came with the mission of creating their own passive solar home. The NaturalFlow system was an obvious choice, being power-free. We were able to help them achieve their dream on this awesome property.

Off-grid, tiny homes
14 December 2023
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Family Home

The EconoTreat was perfect for this family home. With higher volumes of waste and council requirements of secondary treatment, they needed a system that would provide a consistently high treatment.

14 December 2023
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Packhouse Accomodation

With large seasonal fluctuations, this kiwifruit packing facility needed capacity for peak season staff. A custom designed system by WaterFlow met the requirements for the project, with the capacity to process up to 54,000L per day.

14 December 2023
Read More

Otamatea Marae

Struggling to have enough water to sustain the events, we were asked to upgrade the water tanks and drainage. With an additional four 25000L tanks, they aren’t likely to run out any time soon!

Marae & Light Commercial
14 December 2023
Read More

Rural Oasis

The Naturalflow NF8000 System was used in this piece of paradise. The landscaping gives it a tropical feel, as you step through to the pool for some quality time out.

14 December 2023
Read More

Bahá’í – Henderson

With major upgrades to the building and facilities, the Spiritual Assembly of the Bahai’s was in need of an upgraded wastewater system.

Marae & Light Commercial
01 December 2023
Read More

It all starts with your site

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Your site and dispersal field have the biggest say in which system will work best for you. Let our team take a look, either on site or via aerial mapping, and we can help you find a solution that works for you.

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