Tweed Shire Council has issued an amber alert for blue-green algae in the Tweed River at Uki, two weeks after declaring an amber alert for Clarrie Hall Dam.
Council’s Water and Wastewater operations Manager Brie Jowett said the amber alerts meant blue-green algae might be multiplying in the affected waterways.
However, Mrs Jowett stressed tap water across the Tweed including at Uki, remained safe to drink and bathe in.
‘We have a water treatment plant at Uki and it draws and treats water from the river for the local community,’ said Mrs Jowett.
‘The heavy rain earlier this week increased the amount of water spilling from the dam, with the water flowing down Doon Doon Creek into the Tweed River upstream of Uki.
‘This is the most probable reason why our scientists at the NATA-accredited Tweed Laboratory have just detected blue-green algae in the river at Uki.
‘We will continue to ensure drinking water throughout the Tweed is treated appropriately for the conditions.’
Mrs Jowett said the algae detected in the dam and river was not a species capable of producing toxins.
Water treatment process is robust
However, she stressed even if toxin-producing algae was present, Council’s water treatment processes were robust. ‘We remove blue-green algae from our treated water whenever blooms occur, so our tap water would still be perfectly safe to drink and bathe in.’
Water for most of the Tweed is sourced from the Tweed River downstream at the Bray Park Weir. The village of Uki has its own treatment plant, drawing water from the Tweed River at Uki. The village of Tyalgum has its own water supply – the Oxley River at the Tyalgum Weir.
Council is monitoring the situation and maintaining testing twice a week at the dam, the Tweed River at Uki and Bray Park, and weekly from the Oxley River at Tyalgum.
Blue-green algae occurs naturally
Blue-green algae occurs naturally and can reproduce quickly in still or slow-flowing water when it is warm and sunny and the water is nutrient-rich.
Affected water can appear to have a green, paint-like scum on the water, near the edges, or greenish clumps throughout the water. It can have a musty odour.
Mrs Jowett said Council was taking a precautionary approach and advising against recreational activities in the Tweed River at Uki and Clarrie Hall Dam. ‘At this time, do not swim in, kayak on or touch water in the affected waterways.
‘Do not drink or eat fish and shellfish from the waterway and keep animals away.
‘Please remember, never drink untreated river water at any time. During any blue-green algae bloom, do not water livestock with untreated river water.
Seek medical advice if symptoms appear
‘If you come into contact with the algae, rinse it off with fresh water and seek medical advice if symptoms appear.’
Warning signs are going up at public access points to the Tweed River near Uki to inform the public of the presence of blue-green algae and any potential risk.
Warning signs remain in place at Crams Farm and the Clarrie Hall Dam wall.
For the latest update on algae alerts, visit Council’s website at tweed.nsw.gov.au/recreational-blue-green-algae-alerts.
