Wastewater Treatment

Wastewater treatment is the process used to remove contaminants from wastewater or sewage and convert it into an effluent that can be returned to the water cycle with a minimum of impact on the environment.

Findlater Construction manufacture and install both primary and secondary wastewater systems suitable for residential or commercial use. Our trained servicemen service these and other systems.

Wastewater Services

Primary and Secondary Wastewater Systems

Where no council, or any other, reticulated sewer is available to connect to, such as in rural communities, wastewater is then generally treated with an “on-site wastewater” system. Such systems use a traditional septic tank, followed by an effluent disposal bed, from which the effluent soaks into the ground, this is a primary wastewater system.

If the site characteristics aren’t suitable for a primary wastewater system, then a secondary wastewater system would be usually installed.

Secondary wastewater systems treat wastewater to a higher standard than primary septic tank systems and there are many different types of secondary wastewater systems. They dispose of the treated wastewater to land usually via wastewater drip line, effluent disposal beds, eco mounds etc.

The most popular secondary types of wastewater systems are AWTS’s (Aerated Wastewater Treatment System), with PBR (Packed Bed Reactor), SBR (Sequencing Bed Reactor) and others also available.

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Around 2011 Findlater Construction started manufacturing septic tanks in our Blenheim yard, followed a little later by aerated wastewater systems, grease traps, pump chambers, and more.

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Findlater A2000 Aerated Residential Wastewater System

Our A2000 system is an aerated secondary wastewater system. Aerated systems use proven technology to produce high levels of wastewater treatment. This method of treatment is commonly used in municipal treatment plants worldwide.

The Findlater A2000 wastewater systems have been available since 2012, and they have performed reliably, treating wastewater to a high standard and with few problems.

In NZ, wastewater systems are performance tested by the OSET (On-site Effluent Treatment) trials held at the Rotorua City Wastewater Treatment plant. We had our A2000 system tested in 2012 at Trial 8 where it performed admirably. As the OSET programme is changing we are having our system re-tested, Trial 15 starting early 2020, with results available in March 2021.

We are proud to say that we have only made few minor changes to the A2000 system for the latest round of testing, at the 2020 OSET Trial 15.

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Commercial Wastewater Systems

We have been installing, servicing and modifying commercial wastewater systems since the 1990’s.

The commercial wastewater field can be challenging, with careful consideration needed when making buying decisions, and in choosing the people to work with.

We manufacture and install small to medium sized commercial wastewater systems and would welcome your enquiry.

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Wastewater System Design

In deciding which is the most suitable wastewater system for a site, an engineer or wastewater system designer are employed to investigate the site conditions and wastewater loadings. They provide an “on-site wastewater“ report, which is required by regulatory authorities to obtain a building consent or other consents so a new or upgraded wastewater system can be installed.

The report will investigate the soils, terrain, ground cover, topography, groundwater levels, proximity to water bodies, potable water supply, wastewater loadings, and whether a primary or secondary system is most suitable. It will consider all options and make recommendations as to the most appropriate wastewater system for that site.

We are accredited by several local authorities to provide wastewater reports.

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Decentralised Wastewater Treatment

In areas where there is no municipal sewer system a decentralised wastewater system may be installed to service several buildings/sections. An evaluation of site-specific conditions and loadings will be required to determine the most appropriate approach and type of system.

Findlater Construction have designed and constructed decentralised wastewater systems at the Koromiko Airpark and Portage Sub-division.

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Wastewater Projects

Frequently Asked Questions

Typical locations where on-site domestic wastewater systems are used to service properties and dwellings in areas where there is no sewer reticulation, include:

  • Areas such as the Marlborough Sounds or other Coastal Areas
  • Rural residential subdivisions
  • Lifestyle blocks
  • Remote Areas such as High country cabins/huts

We can advise you on if you need an on-site septic system or if you are able to connect to a mains sewerage system.

We can help you with this. This is based on many factors including the location, soil type, how much room you have and how many people live on the property.

Therefore it is best to get Findlater Construction to carry out a site inspection to devise the best system for your property. Give us a call on 03 579 2284 if you’d like to arrange an on-site inspection.

Septic Systems – Commonly known as a septic tank and soakage trench or bed, the traditional septic tank and soakage trench systems work well for large lots (1/4 acre or more), but have limitations in clay soils or gravelly soils. A primary septic systems does not treat wastewater in any way, they simply work to reduce solids before discharging the liquid to the soakage trench.

Aerated Treatment Systems – An aerated treatment system pre-treats wastewater before discharging in a controlled manner to a land treatment area on-site. They are able to be used in less than ideal soil conditions and work to reduce harmful groundwater contamination. We can retrofit a system to improve its treatment of your wastewater before discharging to a land treatment area.

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We strive to build a robust, high quality wastewater system that will work well and stand the test of time.

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