SATELLITE pictures from New South Wales’ peak water authority show the current state of blue-green algal blooms in the Lower Darling River system.
The images, taken on January 7 and released last week as part of an overall report on the current state of blue-green algae growth in WaterNSW managed parts of the Murray-Darling Basin, show increasing blooms along the Great Darling Anabranch and in the Menindee Lakes.
The pictures were captured and accompanying report released ahead of increased water flows through the Menindee Lakes and the opening of Weir 32 which was aimed at increasing oxygen levels in the lower lakes’ system and avoiding a mass fish kill event.
At the same time the report was released, Water NSW announced it would be increasing flows out of the lakes and into the Lower Darling from 750 megalitres to 1500ML for 48 hours from January 10.
“This blue-green algal alert report is based on routine monitoring at sites in the Murray and Sunraysia Algae Reporting Area,” the report said. “The sites are monitored by WaterNSW and local water authorities.
“The satellite image of the Menindee Lakes … shows very low-level to low phytoplankton activity in lakes Wetherell, Tandure, Pamamaroo and Copi Hollow.
“Phytoplankton activity in Lake Menindee ranged from very low to medium.
“Lake Cawndilla had low to medium level algal activity. Weir 32 weir pool had very low to medium phytoplankton activity.
“The Murray River near Wentworth had very low phytoplankton activity … while the Anabranch appears to have had medium phytoplankton activity.
“The lower Darling River had very low to medium phytoplankton activity.”
The Water NSW report said forecast conditions were expected to be “favourable” to increased blue-green algae.
“At Menindee, days are forecast to be mostly sunny,” the report said. “Maximum day air temperatures are expected to be between 30 degrees and 42 degrees with minimum temperatures ranging from 14 degrees to 25 degrees.
“These environmental conditions are expected to create favourable circumstances for blue-green algal growth.”
As of yesterday, red alerts for blue-green algae remained in place for Ellerslie on the Lower Darling and the Silver City Highway crossing of the Great Darling Anabranch, as well as at a testing site in the Menindee Lakes above Weir 32.
The red alerts that had been in place at Pooncarie and Tolarno have been changed to amber.
Along the Murray River the blue-green algae alerts was listed as either green or amber level.
Sites at Mount Dispersion, Merbein, and Fort Courage were all at amber, while Euston/ Robinvale, Buronga, Lock 9 and Lock 8 were marked green on WaterNSW’s algae alerts map.
