Waitākere Ranges reporting area

Waitākere Local Board

State of Auckland

Freshwater
Report
Card

Area Grade

A

July 2014

What makes up this grade?

What-makes-up-this-grade_FRESH-WATER-WR-2014

The overall grade is made up of five indicators:


Water quality: Water samples are tested for temperature, oxygen concentration, turbidity and the levels of pH, ammonia and nutrients (nitrogen and phosphorus). The results of this testing are compared against guidelines for Auckland to produce a water quality index.

Flow patterns: This involves monitoring the hydrologic connectivity of the river to upstream and downstream reaches and the floodplain using the Stream Ecological Valuation (SEV), which is a method of assessing the ecological health of our rivers.

Nutrient cycling: This involves monitoring the inputs and processing of minerals, particulates and contaminants using the SEV biogeochemical functions.

Habitat quality: This involves monitoring the diversity and quality of habitats using the SEV habitat provision functions.

Biodiversity: Field assessments and samples are collected to assess the type and amount of native plants
and animals using the SEV biodiversity functions.

Quick facts

The reporting area covers 297KM2 representing 6.1% of the region – the seventh largest reporting area

The land cover of is mainly native vegetation (82%) 

The extent of impervious surface (hard surfaces) is low (5%) when compared with the regional average of 9% 

Annual-rainfall_FRESH-WATER-WR-2014

Waitākere Ranges monitoring sites map

Monitoring background and interpretation

Auckland Council’s State of the Environment (SoE) monitoring programme has been building a record of Auckland’s environment for more than 25 years. This information is critical to the effective management of Auckland’s natural environment, after all, you
can’t manage what you don’t monitor.

The monitoring programme shows there is a strong relationship between the health of rivers and the type of land cover in the surrounding catchment. Rivers that drain through forested catchments (particularly native forests) typically have excellent water quality and ecology, while rivers that drain from urban catchments typically have poor water quality and ecology.

The Waitākere Ranges reporting area is predominantly forested and as a result the health of the area’s rivers is considered to be excellent. Rivers in this reporting area tend to have riparian margins with lots of trees and bush, which provide shade, leaf litter and woody debris to the stream. These additions to the stream enhance the quality of flora and fauna which anchor the stream banks. The absence of urban development means there is very little channel modification or pollution from discharges or stormwater. 

Wai Care Waitākare Ranges

wai care logo

Wai Care is a water quality education, monitoring and action programme managed by Auckland Council, for schools and community groups in the Auckland region.

The programme aims to educate people about freshwater issues and encourage and facilitate action in the local community, from water quality monitoring to streamside planting and litter clean-ups.

The following table shows achievements of the Wai Care Programme in Waitākere during the 2013/2014 financial year.

TABLE_FRESH-WATER-WR-2014

Highlights

Henderson Valley School’s ‘Stream Team’ meet every term with Wai Care to monitor their local site on the Opanuku Stream. The group of students from years 4 to 6 are experts on their site and have made videos and presentations to share with other students
and the community. 

For more information on Wai Care, or to view site data for your area, go to www.waicare.org.nz or call 09 301 0101 and ask for Wai Care.