Blue-green algae alert lowered for majority of Lake Albert
Published: 10 May 2018 11:33am
The blue-green algae alert for the majority of Lake Albert has been lowered, with a 30m exclusion zone in place at the northern and eastern shore of the lake.
Blue-green algae is still visually present in the exclusion zone and Council advises the community against making contact with the water in this area, or where an algal scum can be seen.
Council regularly conducts water quality monitoring at Lake Albert in line with National Health and Medical Research Council (NHMRC) guidelines, with the current alert first issued on 21 December 2017.
For an alert to be downgraded there must be two consecutive samples at a low level and no algal scums present.
Samples have returned lower levels of cyanobacteria and Council staff have been working closely with the organisers of this weekend’s Barry Carne Interstate Ski Challenge to minimise any impact on the event.
“Staff have been regularly testing the water throughout the alert period and while there have been lower readings at times, the algae has still been visually present,” Wagga Wagga City Council’s Manager Environment and City Compliance Mark Gardiner said.
“A range of factors contribute to higher blue-green algae levels and at Lake Albert the continuing warm weather and low rainfall have seen the algae persist for a number of months.
“With the current cold weather pattern there has been a significant reduction in the blue-green algae present in the lake and the westerly winds are containing it to the north and east sections of the lake.
“We have put a 30m exclusion zone in place in this section, which is marked with signs on the shore and buoys on the water.”
Work continues on long-term options to improve water quality
Along with monitoring the current situation at Lake Albert, staff have been investigating long-term options to increase water levels and improve water quality.
“Council has been investigating a range of options to manage water quality at Lake Albert,” Strategic Asset Planner (Parks & Recreation) Ben Creighton said.
“These are still high level concepts to be researched further so we can assess how effective they may be in improving the lake’s water quality.
“The designs, costings and modelling for the Tatton stormwater catchment project are also complete and Council is now looking at grant options to fund the works.”
Council has also been liaising with researchers from Sydney University, who have expressed an interest in studying the lake and have applied for state funding to undertake the project.
What is blue-green algae and why does it appear in Lake Albert?
Blue-green algae can appear as specking, suspended clumps or as algal scums that take the form of green or yellow discoloured slicks on the water surface.
Algal blooms generally occur in waters rich in nutrients and thrives in dry, warm conditions.
“Lake Albert’s water level is reliant on stormwater from the catchment area,” Mr Gardiner said. “Conditions have been highly favourable for blue-green algae growth with little rain this year and warmer weather continuing through autumn.
“Along with thriving in warm conditions, blue-green algae is found in waterways high in nutrients, particularly phosphorus. Without regular rainfall, Lake Albert receives a high dose of nutrients from the stormwater when it does rain, such as from fertiliser and animal faeces, which can cause blue-green algae to persist.
“With cooler weather and rain forecast, the cyanobacteria will become less prevalent and we will continue to monitor the lake closely.”