Freshwater Toxic Algae Monitoring
Toxic algae are assessed in accordance with New Zealand guidelines for cyanobacteria in recreational freshwaters: Interim guidelines (2009). 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.
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.
Use the tabs below to see toxic algae cover at Tier 1 and Tier 2 sentinel sites in respective Whaitua for the 2020/21 summer season, then hover over points on the graphs to see specific values, or on legend entries to highlight that series.
Te Whanganui-a-Tara
Tier 1 sites
Tier 2 sites
Ruamāhanga
Tier 1 sites
Tier 2 sites
Kāpiti Coast
Tier 1 sites
Tier 2 sites
