Summer 2022/23 toxic algae are assessed in accordance with New Zealand guidelines for cyanobacteria in recreational freshwaters: Interim guidelines (2009) and presented in the charts below. The green (⬤) and blue (⬤) dots show observed toxic algae cover by transect and bankside assessment methods with red circles (◯) around them if detached toxic algae mats were present. River flow is shown by the continuous black line () and the orange ( ) and red ( ) dotted lines mark alert (>20%) and action (>50%) levels of toxic algae cover respectively.
Click on the tab headings to see charts for each Whaitua and scroll down to see sites grouped by their monitoring tier in the Sentinel Site Framework, see the methods page for more information on this framework. Other sites that are monitored for toxic algae but not assigned a tier are included for reference as well.
Hover over points on the graphs to see specific values, and hover on legend entries to highlight that series. Note that the y-axes for flow (right side of plots) are on different scales across sites, this is to highlight the possible effect of relative flow events on toxic algae cover rather than comparing absolute rates.
Tier 1 sites
Tier 2 sites
Other sites
Tier 1 sites
Tier 2 sites
Other sites
Tier 1 sites