Tweed Council is wanting to reassure residents that treated water from the Tweed mains supply remains safe to drink despite alerts for blue-green algae being extended in the Shire.
Today, amber alerts for blue-green algae were issued for the Tweed River at Uki and Bray Park Weir. Last week an amber alert was issued for Clarrie Hall Dam.
Council testing has shown the level of blue-green algae has quadrupled at the dam in the past week, most likely due to the high level of nutrients washed into the dam by the December rains and continuing hot weather. Despite this, potentially toxic species of blue-green algae currently are not dominant.
Weir is full
The dam is full and spilling to Doon Doon Creek, a tributary of the Tweed River, allowing algae to flow downstream to Uki and Bray Park Weir.
Council draws raw water at Uki to treat at the village’s water treatment plant and again at Bray Park Weir to treat for the bulk of the Shire’s water customers.
Council’s water treatment processes are designed to remove any potential toxin from blue-green algae. Treatment also removes any taste and odour compounds from the algae.
Council will increase testing to monitor the algal blooms, and adjust its treatment processes as required to ensure the Tweed’s drinking water remains safe to drink and pleasant tasting.
Amber alerts mean recreational users of the dam and river should not come into contact with the water and livestock should not drink the water as it could potentially be toxic.
Signs have been placed at popular recreational access points to warn the public of the risks.
Blue-green algae occur naturally and can reproduce quickly in favourable conditions.
Affected water appears to have a green paint-like scum, near the edges, or greenish clumps throughout the water.
Anyone who thinks they may have been in contact with blue-green algal water is advised to seek medical advice if symptoms appear.
For the latest, visit Council’s website at www.tweed.nsw.gov.au/waterandwastewater.
As far as I am aware blue-green algae commonly occurs in this area during dry periods when nutrients build up in the low water levels. The fact that the dam is full and blue-green algae is present rings alarm bells for me, since I would consider that excess nutrients are running into the dam, ie pollutants in the form of nutrients.