What is the East Rotoiti Rotomā Sewerage Scheme?

    The East Rotoiti Rotomā Sewerage Scheme (the Scheme) aims to protect the health of the waterways, the health of the public, and to provide an essential service to the community. The Scheme will provide an essential service to approximately 680 households and has the capacity for future developments.

    Included is a wastewater treatment plant built behind the Rotoiti Emery Store, and a reticulation network that connects homes in Rotomā and East Rotoiti to the plant. Each property will have a preliminary on-site system that provides a high level of pre-treatment, a condition of the Resource Consent and Cultural Management Plan. This reduces the risk of para reaching waterways in the event of a breakage or damage to the pipes.

    What is the purpose of the East Rotoiti Rotomā Sewerage Scheme?

    Water quality has been declining in several Rotorua lakes, including lakes Rotoiti and Rotomā over a period of time and this is why organisations are now working together to help stop the rising nutrient levels.

    For Rotoiti and Rotomā, domestic septic tanks contribute to the diminishing water quality as they are a source of pathogens and nutrients (nitrogen and phosphorus).  One of the most effective ways to improve water quality (and protect the lakes) is to remove old septic tanks and replace them with a new system to collect human wastewater, reticulate (pipe) it to a wastewater plant where it can be treated and disposed of. 

    The scheme is a key component of the Lake Rotorua and Rotoiti Action Plan (External link) devised under the programme.

    What areas will the East Rotoiti Rotomā Sewerage Scheme cover?

    The scheme will service properties from Curtis Rd (east Rotoiti) through to Matahī Spit (Rotomā).

    What wastewater pre-treatment system will be installed in Rotoiti?

    There has been a thorough and robust process to select the system that best meets the required performance criteria including operational effectiveness, system safety, effluent performance, cultural alignment and long-term cost effectiveness. The awarded system for East Rotoiti is Biolytix BF2. This is the system that also met the earlier trial criteria.

    The Biolytix BF2 Eco Pod (system) is the approved on-site wastewater system for East Rotoiti. There will be one system installed per dwelling, and it will sit below the ground surface with an access cover above ground. It is connected to the electrical panel of the house. The system uses micro-organisms, and tiger worms, to break down organic material. This is a natural process that reduces any offensive odours from wastewater.

    When wastewater enters the system, solid waste is separated from liquid using filter beds. Tiger worms and other organisms break down waste solids and convert them into liquid.  The tiger worms live throughout the filter bed, naturally aerating it, and wastewater is broken down by microorganisms as it trickles through the filter bed. The treated wastewater is then pumped from the on-site system through the local reticulated network to the main Wastewater Treatment Plant on Haumingi 9B3B for final treatment and disinfection prior to discharge. 

    For more information about the system visit www.biolytix.com or contact Council on 07 348 4199 to speak to an engineer about how the process works.

    What is the Rotoiti Rotomā Sewerage Steering Committee?

    It is a community committee that was set up in 2014 to explore options for an East Rotoiti | Rotomā Sewerage Scheme for its hapori (community).   

    Over several years the community-led Rotoiti Rotomā Steering Committee (established in 2014) oversaw the decision making to identify the best onsite pre-treatment for installation on properties. 

    How did the Rotoiti Rotomā Sewerage Steering Committee pick a preferred option?

    At the core of the committee’s work were environmental, social, and cultural values. These values informed solutions to provide resilience in the technical aspects of the reticulation network and the wastewater treatment plant in every day usage, as well as in the event of emergencies (e.g. earthquakes).

    What involvement has the Cultural Impact Team had in the scheme?

    Ngāti Pikiao Cultural Impacts Team provide specialist cultural and technical knowledge to the project. The team ensures that the recommendations of the two cultural impact assessments (one for the reticulation network, and one for the Haumingi 9B3B wastewater treatment plant site) are incorporated into the Council’s planning, design, construction and operation of the Scheme.

    How much is the overall cost of the scheme?

    The estimated cost of the scheme will cost a total of about $51m. 

    Funding contributions:
    Ministry of Health - $4.46m
    Bay of Plenty Regional Council - $8.62m
    Ministry for the Environment - $21.65m
    Rotorua Lakes Council - $1.15m

    How much will homeowners contribute to the scheme?

    Council remains very aware that the final cost is a concern for residents and it’s important to note that every effort has been made to constrain final costs.

    there will be a capital contribution from landowners for the system. This capital contribution won’t need to be paid until the scheme is completed (under current Council decisions) and the full, actual costs are settled. This will likely be in two years’ time (2023). 

    All scheme participants will pay the same charge (except some community facilities such as schools, marae and sports clubs due to their importance to the community). Council’s advice is that it will continue to pursue the goal that the lowest possible net costs are achieved for the local ratepayers.  

    There will also be an annual operating cost per annum, which is equalised across Rotorua district to all properties connected to a wastewater scheme. This operating cost covers maintenance, repairs and system renewals.

    Where is Wastewater Treatment Plant?

    The wastewater treatment plant is behind the Rotoiti Emery Store, on land owned by Haumingi B93B. 

    How does the Wastewater Treatment Plant work?

    The treatment plant uses natural bacteria (to remove nutrients), a membrane bio reactor (to filter and remove more nutrients), Ultraviolet (UV) light (to disinfect in the same way that the sun does), and then irrigating to pumice soils (providing additional natural filtration and safe dispersal).


    What is a STEP system?

    STEP stands for Septic Tank Effluent Pumping system.  It is an on-site wastewater pre-treatment system.

    How does the STEP system work?

    The STEP system comprises of a septic tank with a pump.  It pre-treats wastewater, which is then pumped to a central piping network and on to a treatment plant.  The outflow is highly treated at the treatment plant before it is released on to land. 

    What to do if you have a concern about the STEP system

    For any issues please phone council on 07 348 4199 (24/7)

    Who will be responsible for maintaining the STEP system?

    Council is responsible for the maintenance of your STEP system