Omaha WWTP – Land Discharge Consent & Beneficial Re-Use Outcomes

This project involved the replacement of the previous resource consents for the Omaha Wastewater Treatment Plant (“Omaha WWTP”) treated wastewater discharges. The Omaha WWTP is located ~70km north of Auckland on Jones Road, Omaha Flats. It treats wastewater from Omaha, Point Wells and Matakana. Treated wastewater is discharged to land at forestry blocks within the Omaha WWTP site itself, and to the Omaha Beach Golf Course (“OBGC”). There is no direct discharge to water but the irrigation areas border the Whangateau Harbour which contains substantial ecologically significant areas. At the OBGC, treated wastewater is used to irrigate fairways, tees and fringes primarily during summer-autumn, via subsurface drip irrigation. The irrigation is of great benefit to the OBGC, reducing their freshwater and fertiliser usage. Watercare work in tandem with the needs of the OBGC, to keep the irrigation supply available to provide summer irrigation. A multi-disciplinary team was brought together by Watercare to assess the existing and future environmental impacts from the discharges, and the capacity of the land application sites to accommodate additional volume to meet projected growth. Central to the replacement of the resource consents was the formation of the Omaha WWTP Consultative Group. The extensive engagement included their participation in scoping an investigation plan for the project, consideration of the results of these investigations and discussions of how subsequent stages of the investigation should proceed. Technical experts presented the results of their work to the Omaha WWTP Consultative Group, who were able to discuss the findings directly with the experts. The technical work and consultation process took nearly three years and resulted in widespread community support for a formerly contentious discharge. Replacement consents were recently granted for the Omaha WWTP with 35 year durations and no capital upgrade requirements.