The Red Alert warning for the Wyangala Dam Abercrombie River arm (site DWYA05), has been lifted following two consecutive laboratory analysis results below red alert level.
While the Abercrombie River arm is now on green alert, there is still a red alert warning in place for the Sandy Creek arm, and amber blue-green algal alerts for other areas within Wyangala Dam, a media release from Water NSW issued Friday afternoon says.
A red alert level warning indicates that people should not undertake recreational activities where they may be coming into direct contact with the water such as swimming, as well as domestic uses including showering and washing.
Contact with the water may also pose a threat to livestock and pets.
While on an amber alert, the water is generally considered to be suitable for water sports, but water users are advised to exercise caution.
It is also advised not to drink untreated or boiled water from the storage due to the risk of stomach upsets. Boiling the water does not inactivate algal toxins.
The water should be considered unsuitable for potable use and alternative supplies or prior treatment of raw water for domestic purposes should be considered.
As algal numbers can change dramatically with changes in conditions, water uses should avoid water which is discoloured or gives off an earthy or musty odour.
Water users should use personal discretion at all times before entering a water body and be aware that the algal situation can change quickly.
WaterNSW will continue routine water quality monitoring and advise of any change as new results are received.
Blue-green algae occur naturally and can reproduce quickly in favourable conditions where there is still or slow-flowing water, abundant sunlight and sufficient levels of nutrients.
Blue-green algae usually appear as green paint-like scums on the water, near the edges, or as greenish clumps throughout the water. It makes the water appear dirty, green or discoloured and generally has a strong musty or earthy odour.
Updates and information about blue-green algae blooms and Red Alert warning areas can be obtained by calling 1800 999 457 or visiting - http://www.waternsw.com.au/water-quality/algae