Fact Sheet 5, Water Services Act 2021

    Drinking Water Acceptable Solution

    Acceptable Solutions provide drinking water suppliers with a ready-made option to meet their compliance obligations under the Act.

    They apply to particular supply types and situations and must be implemented in their entirety.
    If your existing supply fits the requirements of an Acceptable Solution or you choose to adopt an Acceptable Solution for a new supply, there is no need to have a WSP or comply with the Drinking Water Quality Assurance Rules 2022. These requirements are all covered in a very bespoke way in the Acceptable Solution you chose for your supply.

    The three available Acceptable Solutions are for the following source water/supplies:

    • Mixed-use rural water supply – where 50% or more of the water supplied is intended for agricultural or horticultural purposes.
    • Roof water supply – where water is supplied to a building or group of buildings which share the same water source.
    • Spring or bore water supplies – where drinking water is supplied from a bore or spring.
    • More acceptable solutions to come.

    To be able to adopt an Acceptable Solution, the source water must meet the criteria set out in the Acceptable Solution, so it is suitable for the proposed treatment. Typical applicable criteria to be able to adopt Acceptable Solutions are listed below:

    • The population served by the entire drinking water supply must be less than 500 people. This does not apply to the mixed-use rural water supplies, where the population limit is per building or group of buildings.
    • Any treatment system must be designed to meet the peak instantaneous demand for treated water.
    • The water supplied to a building, or group of
      buildings, must share the same roof water source.
    • Water abstracted from a bore or spring must be tested to demonstrate specific raw water parameters are within specified limits to ensure the treatment process proposed by the Acceptable Solution is suitable. This applies for example to iron, manganese, alkalinity, UV transmittance and turbidity.

    Each Acceptable Solution will require:

    • Operations and Maintenance (O&M) Manual and Standard Operating Procedures (SOPs).
    • Maintenance, inspection, calibration.
    • Monitoring and testing.
    • Incident management.
    • Training.

    The treatment prescribed in the Acceptable Solutions consists of end-point treatment system made of cartridge filtration followed by UV disinfection. Acceptable Solutions are not headworks treatment systems.

    There is no chlorination requirement in the Acceptable Solutions. Disinfection occurs with the UV treatment, but disinfection residual is unnecessary when there is no network downstream of the point of disinfection. The population limits per building (500 people) and group of buildings (100 people) ensure the lack of chlorination is safe and appropriate.

    Water quality testing and backflow prevention must be carried out as set out in the Acceptable Solution adopted. The maximum population is 500 people, except for the mixed-use rural water supply, where the population limit is only per end-point treatment system as noted above.

    All New Zealanders need access to SAFE drinking water.

    Download this free guide to help understand the Reform of the Water Sector (Drinking Water) in New Zealand and the new Water Services Act 2021.