Results from the monitoring programme are assessed against the coastal water quality standards outlined in the Northland Regional Coastal Plan (RCP), ANZECC guidelines and the Ministry for the Environment (MfE) Microbiological Water Quality Guidelines.
· Bacteria - During 2008-09, concentrations of enterococci bacteria were low at all sites and compliance with the MfE guidelines was 99% throughout the Bay of Islands.
Enterococci are micro-bacteria, which are indicators of faecal contamination.
· Nutrients - During 2008-09, compliance with the guidelines for total phosphorus (TP) was 78%, and generally good at most sites. However, sites in the Opua Basin, Waikare Inlet and the Kawakawa River recorded lower levels of compliance.
· High concentrations of dissolved reactive phosphorus (DRP) were recorded at a number of sites throughout the Bay of Islands and overall compliance against the guidelines was low at 45%.
· High concentrations of ammonia were recorded at sites in the Waitangi River, the Waipapa River, Kerikeri River, Wainui Island in Kerikeri Inlet and the Upper Kawakawa River. Overall compliance throughout the Bay of Islands was 63%.
Phosphorus is a nutrient that is essential for plant growth however too much phosphorus in a water body can cause excessive plant growth, which can lead to a reduction in water quality and toxic algal blooms. Ammonia is a nutrient that occurs in a number of waste products, and this may be toxic to some organisms.
· Bacteria - During 2008-09, concentrations of enterococci bacteria were low at all sites and compliance with the MfE guidelines was 99% throughout the Whangarei Harbour.
· Nutrients - High concentrations of TP were recorded at most sites in the harbour and there was a low level of compliance with the guidelines at all sites between One Tree Point and the Town Basin.
· Concentrations of DRP were high at sites between Onerahi and the Town Basin and compliance with the coastal water quality standards was low. Overall, compliance with the water quality guidelines was 22% throughout the harbour.
· Concentrations of ammonia exceeded the guidelines at sites between Onerahi and the Town Basin and overall compliance with the guidelines was 41%.
· Bacteria - During 2008-09, concentrations of faecal coliforms were below MfE microbiological guidelines for shellfish gathering waters at eight of the nine monitoring sites. At the site off Cape Horn, the median concentration of faecal coliforms exceeded 14 faecal coliforms/100ml and more than 10% of samples from this site exceeded 43/100ml.
In addition to the existing water quality programme, a new monitoring programme will be established in the Hokianga Harbour in 2009-10 and a pilot water quality programme will be initiated in the Kaipara Harbour. The Council is successfully working on these projects with the Auckland Regional Council in the Kaipara Harbour and the Far North District Council/Waiora Hokianga group in the Hokianga Harbour.