INTERIM Blue-Green Alage Management Protocols Released
Date: 24 November 2009
Originally published in November 2001, the Blue-Green Algae Management Protocols was revised in 2007 to ensure their consistency with the Australian Drinking Water Guidelines 2004. The Draft Blue-Green Algae Management Protocols was sent to all member councils in January 2007 on CD rom. Both the 2001 and the 2007 Blue-Green Algae Management Protocols were prepared by Adrian Farrant, Public and Environmental Health Consultant, for the Water Directorate.
In October 2009 the NHRMC released the DRAFT Australian Drinking Water Guidelines 2009 and invited submissions. In this document, the NHMRC included new alert levels for toxic blue-green algae for raw water storages. It is noted that blue-green algae occur in all natural waters and are of no concern in small numbers. Health risks can arise from ingestion of cyanobacteria (blue-green algae). The NHMRC sugggests that water authorities use the following target levels to determine the next course of action:
500 cells/ml — increase monitoring;
2000 cells/mL — consider need for toxicity testing (seek expert advice);
The NHMRC alert level limits in the DRAFT 2009 ADWG have been included in the latest version of the Water Directorate’s document, INTERIM Blue-Green Algae Management Protocols. At this stage we are unsure if the NSW Algal Advisory Group will adopt the draft NHMRC alert levels for toxic blue-green algae in raw water storages. The Water Directorate will endeavour to update our INTERIM Protocols to reflect any changes to alert levels by the NHMRC or the NSW Algal Advisory Group.
The Water Directorate believes that the distribution of these INTERIM Blue-Green Alage Management Protocols to member councils will ensure that the chance of blue-green algae incidents in the oncoming high-risk summer period will be greatly reduced.
Any queries about the status of the DRAFT NHMRC alert levels or the INTERIM Protocols can be forwarded to Gary Mitchell. A full copy of the revised Australian Drinking Water Guidelines 2009 can also be viewed on the NHMRC website and the closing date for submissions is 15 January 2010.
