2016-02-02 P&O Committee - Item 3 - Attachment 3 - Noosa River Environmental Values and Water Quality Objectives

Noosa River environmental values and water quality objectives




Table 5 Primary contact recreation EV: Water quality objectives for management of cyanobacteria in
contact recreation areas

When cyanobacteria are present in large numbers they can present a significant hazard, particularly to
primary contact users of waters.

 Green level surveillance mode                     Amber level alert mode                      Red level action mode


                           -1                                                  -1
≥ 500 to <500 cells mL                       ≥ 5000 to <50 000 cells mL               Level 1 guideline:
                                                                                               -1
Microsystis aeruginosa                       Microsystis aeruginosa                   ≥ 10 µg L total microsystins
                                                                 3   -1                                       -1
or                                           Or ≥ 0.4 to <4 mm L for the              Or ≥ 50 000 cells mL toxic
                                             combined total of all                    Microsystis aeruginosa
biovolume equivalent of >0.04 to             cyanobacteria where a known
         3 -1
<0.4mm L for the combined total              toxin producer is dominant in the        Or biovolume equivalent of ≥ 4
                                                                                           3 -1
of all cyanobacteria.                        total biovolume                          mm L for the combined total of
                                                                                      all cyanobacteria where a known
                                                                                                                1
                                             Or                                       toxin producer is dominant in the
                                                                                      total biovolume
                                                                     3    -1
                                             ≥ 0.5 to <10 mm mm L for the
                                                                                           2
                                             combined total of all                    Or
                                             cyanobacteria where known toxin
                                             producers are not present.               Level 2 guideline:
                                                                                               3 -1
                                                                                      ≥ 10 mm L for total biovolume of
                                                                                      all cyanobacterial material where
                                                                                      known toxins are not present

                                                                                      Or

                                                                                      Cyanobacteria scums are
                                                                                                          3
                                                                                      consistently present .
Source: NHMRC Guideline for Managing Risks in Recreational Water – Cyanobacteria and algae in freshwater
(NHMRC, 2008).

Notes:

1.     The definition of “dominant” is where the known toxin producer comprises 75% or more of the total biovolume of
       cyanobacteria in a representative sample
2.     This applies where high cell densities or scums of “non toxic” cyanobacteria are present i.e. where the
       cyanobacterial population has been tested and shown not to contain known toxins (mycrocystins, nodularian,
       cylindrospermopsin or saxitoxin).
3.     This refers to the situation where scums occur at the recreation site each day when conditions are calm,
       particularly in the morning. Note that it is not likely that scums are always present and visible when there is a high
       population as the cells may mix down with wind and turbulence and then reform later when conditions become
       stable.




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