FREQUENTLY ASKED QUESTIONS

 

How do I know if I need an onsite wastewater treatment system?
You will require some form of wastewater system if you live outside the reach of a reticulated sewage system as supplied in most cities, town and built up areas.

Why an Oasis Clearwater Environmental System?

Oasis Clearwater Environmental Systems was one of the first wastewater treatment companies to introduce advanced wastewater treatment systems into New Zealand.


The range and size of systems available has grown and adapted to the requirements of the market. Oasis Clearwater Environmental Systems is the only wastewater treatment company to manufacture all their own systems. Systems are available nationwide via a network of dealers dedicated to installation and servicing.

What is the advantage of dealing with Oasis Clearwater Environmental Systems?

For the homeowner, all our systems are designed to protect the country’s natural water quality. With their low operating and maintenance costs, the systems save money, water and protect the environment.


For commercial users such as councils, developers or engineers, the Oasis systems offer high reliability with low maintenance. Our systems deliver proven design and engineering from single to multiple tank systems. We also offer a full range of spares as well as a commitment to ongoing back-up service.

What is the difference between a conventional septic tank and a wastewater treatment system?

A conventional septic tank processes wastewater by anaerobic bacterial activity and coarse filtration only. The effluent must be dispersed via specially formed disposal trenches designed by a drainage engineer.


Wastewater treatment systems contain a septic process but then go through secondary aerated or other treatment. The aerobic bacterial activity in this secondary treatment is more effective at turning wastewater into high grade effluent. Wastewater is treated to such a degree that the effluent produced can be safely disposed of via effluent irrigation driplines.

 

When would a wastewater treatment system be used over a conventional septic tank?

Wastewater treatment systems are able to be used in almost all domestic applications. Septic systems are limited to areas where the soil is well drained and the environment is least a risk.

How do I know which wastewater treatment system is most appropriate?

The type of system you use is dependent on a number of factors including application, loading, council requirements and individual preference.
Oasis Clearwater Series 2000 is suitable for most domestic situations and is the most commonly used domestic treatment system.

TEXASS system produces a superior effluent and is the best option where intermittent duties and varying flows are present e.g. holiday homes.
MBR system produces the best quality effluent, free of virus and bacteria and is used where the environment is most a risk. Water may potentially be used for recycling.

Aren’t wastewater treatment systems smelly and leak contaminants into the environment?

Wastewater systems that are constructed properly are watertight and buried beneath the ground. Because there is no contact with the atmosphere there will be little or no smell if the system is functioning correctly.

Can normal household chemicals be used with a wastewater treatment system?

Biodegradable chemicals are generally safe but bleaches or anything containing bactericides/antiseptics will kill or at least check the helpful bacteria within the system. Should a system begin to function poorly, chemical usage is often the cause.

How often do you have to clean out a wastewater treatment system?

This will ultimately depend on loading. How much and what type of wastewater goes into the system. On an average domestic system, 5 people living a dwelling, it will be around 3-5 years.

How often should the wastewater treatment system be serviced?

In conjunction with local and regional council requirement, a treatment system should be serviced at least 2 times a year. This servicing should be looked at as preventative maintenance to ensure the correct functioning of the system. Good for you and good for the environment.

What other costs are involved?

Depending on where you live your local councils (district and regional) may require that you have your system designed by an engineer. Some councils also charge for the processing of applications to dispose of wastewater onto a site. Check with your local councils.

What’s the best way to dispose of treated wastewater?

Most treatment plants dispose of the effluent via drip or dripline irrigation. The drip irrigation system is installed as an extension of the chosen wastewater treatment system using small diameter, pressure and flow compensating tubing. Tubes are laid in shallow soil (100-150mm) within gardens, grass lands, tree lots and/or shelterbelts as the ideal recipients of the wastewater plant production (effluent).

What advantages does concrete tank construction offer over other construction materials?

Domestically the tanks are constructed with all stages/chambers of the system contained within one tank.
Installation is simplified because there are no special backfilling requirements.
High groundwater levels at the time of installation are less of an issue.
Concrete has the strength and durability needed for in ground installation. The same reason most buildings are constructed on concrete foundations.