Please see update from Council indicating a possible 4th consecutive year of lake closures due to algae outbreaks!
We would like to use our first update of 2020 to remind you that the Bureau of Meteorology has predicted a hotter than normal summer. This may have implications for water quality in Lake Hugh Muntz. It is difficult to predict the timings of algal blooms and how long they will last. We heard from Griffith University at our latest Lake Hugh Muntz Stakeholder Meeting that lower than average rainfall and higher temperatures may increase the likelihood of a blue-green algae bloom this season. While the City monitors water quality weekly, you should still be on the lookout for changes in water quality and not enter the water if you notice the following;
- scums across the surface of the lake, or
- changes in water colour.
Exposure to blue-green toxins can occur through;
- swallowing affected water
- putting your head under water (swimming, canoe capsizing), or
- direct water contact with the skin, including sensitive areas such as the ears, eyes, mouth and nose.
Cyanobacteria Biovolume – 2 January 2020
The below graph compares the average cyanobacteria biovolume at four test locations over the same time period (Nov-Jan) for the last few years. The graph shows that in previous years (the yellow and blue lines) cyanobacteria volumes generally increase during this time of year. Not all blue green algae are toxic and the City monitors for both Total Blue Green Algae (BGA) and Potentially Toxic Algae (PTA), providing health warnings depending on the biovolume of both types.
Current Water Level
The City has received a number of enquiries regarding the current low water level in the lake. The lake has experienced low levels in the past, during the millennium drought and during a period of low rainfall in 2007. The lake is topped up during rainfall events so with the predicted dry summer season, lake levels may remain low for some time.
Monitoring survey of the Lake Hugh Muntz foreshore
The City is preparing to carry out a monitoring survey of the Lake Hugh Muntz foreshore while water levels are low. City Surveyors will be collecting data around the whole of the lake including the foreshore area adjacent to private properties.
The works are scheduled to begin on Monday 13/1/2020 and will be completed by Friday 17/1/2020.
Griffith University Research
This month Griffith University will be on the water in a research boat undertaking a water quality and sediment survey. The survey will provide further data about phosphorus levels in the sediment and water column during the warmer months. This information will be used to help assess how some management options will perform against algal blooms.