What is a low-pressure sewer (LPS) system?

A low-pressure sewer (LPS) system is a type of wastewater collection system that uses small pumps located within each property boundary to move wastewater from individual homes through smaller pipes to a central pump station. 

How does a LPS system work?

All wastewater from the home (from toilets, sinks, dishwasher, washing machine, etc) flows by gravity into a collection tank. When wastewater reaches a certain level, the pump turns on automatically and pumps the wastewater to the sewer main. As it pumps the wastewater, it draws through a grinding mechanism, turning it into a slurry. 

As a purchaser at Park Ridge what do I have to do?

1. Your architect will detail the Ecoflow LPS system on the house plans at the front of the house. 

2. Your builder or drain layer will contact Ecoflow and order their Park Ridge LPS package.  

3. Your drainlayer will install the house drainage system and the Ecoflow LPS system. 

4. The house construction is completed. 

5. Finally, the control system is installed on the side of the house and the LPS system is commissioned. 

6. The LPS system will operate without any user input, flush toilet, take a shower etc as you normally would.

What does the Ecoflow LPS system cost? Where do I purchase it from?

If purchased directly from Ecoflow, the Park Ridge LPS package valid to 31 December 2025 is $8,200 (plus GST). Installation costs will be specified by your drainlayer or builder but are typically around $3,000 (plus GST). The Ecoflow LPS system can be ordered by email info@ecoflow.co.nz or calling 03 349 2506.

Does the Ecoflow LPS system require maintenance?

The LPS system is like any other household appliance such as a washing machine and does not require any regular or preventive maintenance if installed and operated properly. When properly operated, users should expect a reactive service to be performed every 5-8 years. Ecoflow recommends users budget approximately $5/week ($260/year) for reactive maintenance at the service interval.

Where should the LPS system be installed in my property?

The collection tank and grinder should be in the front of the house as close to the house as possible but ideally 2m away from the foundation. The tank may be installed in a garden and the electronic control system, generally on the side of the house. If the collection tank is to be installed below a driveway, then a ‘trafficable lid’ should be selected when the LPS system is purchased. 

Will my builder or drainlayer know how to install the Ecoflow LPS system?

Ecoflow the Park Ridge LPS supplier has provided training to local Queenstown plumbers and drainlayers on ‘best practice’ installation of the pump, collection tank and control box. Park Ridge has also provided popular group home builders a technical information package so they’re familiar with the Ecoflow LPS system, where to order, design requirements and installation guidance. 

What does the LPS system look like once installed?

The collection tank is a small lid easily disguised with planting. The electronic control system is a small plastic box mounted to the side of the house. Both the lid and the controller may be painted to help blend into the garden and house. 

Installed collection tank

What are the benefits of a LPS system and why was it used at Park Ridge?

Benefits to LPS sewage system over a gravity and large centralised pump station network include. 

• Lower environmental impact 

• Large, centralised sewage pump stations can fail and risk discharging sewage into the sensitive downstream ecosystems. 

• At Park Ridge, these include Woolshed Creek, various wetlands and ultimately the Kawarau River. 

• A LPS system which utilises small individual tanks located within each property boundary significantly reduces the risk of a large-scale sewage discharge. 

• Better use of land

• With a LPS network, land usually reserved for large, centralised sewage pump stations, can instead form part of the local Council reserve land, meaning more surrounding open green space for residents to enjoy. 

• Less impact on community infrastructure

• The LPS network is connected to the already constrained Hanley Farm wastewater pump station. 

• By utilising the LPS network, the Park Ridge Development has a lower impact on the existing community infrastructure.

Do I still pay Queenstown Lakes District Council (QLDC) rates for wastewater?

Yes, since the LPS system ultimately connects to a QLDC owned and operated network and treatment facility, QLDC wastewater rates are charged per the relevant policy.  

Can I use other brand LPS systems other than Ecoflow within Park Ridge?

No. Ecoflow is the only brand LPS system which may be used within the Park Ride development. This is because the Ecoflow Control Systems speak to each other to ensure the wastewater network operates as efficiently as possible. Other brand control systems are not compatible. 

I’m intending to build a residential flat connected to my primary dwelling, can I use a single Ecoflow LPS system for both?

Yes, absolutely. Both sewage discharge pipes can operate with a single grinder pump, collection tank and control system. Further details regarding connecting 2 inlets to a single tank can be found in the technical guidance document.

Where can my architect, builder or drainlayer find further technical details?

Technical design information, pump details, operation & maintenance manuals and installation advice can be found via the Ecoflow website https://www.ecoflow.co.nz/technical-info

Are LPS systems widely used throughout the Queenstown Lakes District?

Yes. LPS systems are used at a variety of residential and commercial land developments throughout the district. They are currently in use at the Jacks Point Subdivision, Lake McKay in Luggate and will be used at the Hogan Gully Golf Course currently under construction. 

Which part of the LPS system does the purchaser own and maintain vs what does QLDC own and maintain?

QLDC owns, operates and maintains the boundary kit and sewer main outside the boundary. The resident owns and maintains the electronic control system, collection tank, grinder pump and pipes within the section to the boundary kit. 

 Who do I contact with any further questions regarding low pressure sewer?

In the first instance, please contact Ecoflow directly. The Christchurch branch can be reached in office hours on 03 349 2506, or admin@ecoflow.co.nz. Further information can be found via the Ecoflow website.