"Greywater-Wise" - The Requirement for National Greywater Reuse Guidelines

A recent survey identified the disposal of excess water and reduction of the loading to failing septic tank systems as the key drivers for greywater reuse in New Zealand. As a result, unregulated greywater disposal practices are more common than previously believed, particularly in rural areas of high environmental value. There are increasing demands for greywater systems as the general public becomes more water conscious; particularly as water metering is introduced throughout New Zealand. Some councils, such as Kapiti Coast District Council and Gisborne District Council, have developed specific guidelines for greywater use in their regions. However there is typically extensive variation between different councils, causing confusion and tension between engineers, system suppliers, and local government. The requirement for national guidelines is increasing and will likely need to be addressed in the near future. The Centre for Integrated Biowaste Research (CIBR)’s “Greywater-wise” program is investigating the impacts of greywater diversion and disposal practices on the environment, particularly focusing on the long-term implications for soil, groundwater and public health. The scientific information obtained from these studies will be essential to form the basis of a New Zealand specific Greywater Guideline that takes into account New Zealand’s unique soils and climate.