Tauranga city integrated water management study

While water is plentiful in New Zealand, drinking quality water is becoming a valuable commodity requiring careful management if it is to be available for future generations. Tauranga’s population is forecast to double by 2051, placing increased pressure on the way the Council manages existing infrastructure and levels of service. As a result, drinking water demand management has become an increasingly important tool for Local Government.

Tauranga City Council partnered with GHD to investigate an Integrated Water Management (IWM) approach to developing demand management strategies. Analysis indicates that significant reductions (14 %– 41%) can be made to domestic drinking water demand through implementation of water saving devices (WSD), rainwater tanks (RWST) and greywater reuse. An IWM approach also enabled investigation of the impacts of demand reduction on wastewater discharge and stormwater runoff.

Simplified economic cost benefit analysis indicates installation expenditure is one of the challenges to implementation of WSD, RWST, which needs to be addressed. For the time being, Council will focus on education and incentives through its WaterLine program and improving system losses through pressure reduction and leakage management, while undertaking further assessment of options. Detailed investigation is also required to quantify environmental, social and cultural impacts of water demand management, and to develop truly sustainable water management.