Berowra Creek Algal Bloom Early Warning System
Algal blooms in the Berowra Creek Estuary have been a regular occurrence in recent times. Algae are an integral part of the food web in aquatic systems and provide food for higher organisms such as zooplankton. An algal bloom occurs when one particular type (species) of algae grows much more quickly than other species. This can cause discolouration of the water or a reduction in the levels of dissolved oxygen (which can cause fish kills). Some species of algae can also produce toxins that can be harmful to fish, birds and humans.
In order to better manage these blooms, Hornsby Council commissioned
Manly Hydraulics Laboratory to install a remote monitoring system that
provides an alarm when the chlorophyll-a concentration exceeds 20 mg/L.
The alarm sends an email to staff at Hornsby Council. Once this occurs,
Council takes action as detailed in the Council's algal bloom procedure.
This involves taking samples for laboratory analysis at predetermined
locations to determine what species are causing the bloom and the extent
of the bloom. The procedures detailed in the NSW State Government's Algal
Contingency Plan are also commenced.
