Below are the newsletters / progress reports to date. Regular updates will follow.
Midge control update
Fortunately, an astute and eminently qualified resident has drawn to our attention, serious concerns regarding the midge treatment which I previously incorrectly advised was being undertaken by the City of Bayswater. Following written clarification kindly provided by the City, the correct advice regarding midge control measures it is undertaking is:
- The City of Bayswater has undertaken spraying of Biflex Aqua max, a water-based residual barrier insecticide, on the perimeter vegetation of Lake Brearley and Lake Bungana, to reduce the harbouring midge numbers. It has not sprayed and will not ever spray Biflex Aqua max on any water course. Moreover, it takes take all measures to ensure when spraying that a reasonable buffer is kept between the spray rig and the lakes, so that no off-target drift enters the lakes.
- Piloting a large-scale trailer-mounted wide-mouth insect trap on Lake Brearley. The trap attracts the insects with bright lights, then sucks them into a water tank, where they drown. If this proves effective, the City will build and deploy more traps in the vicinity of the lakes.
- The City of Bayswater has applied for an off-label licence from the Australian Pesticides & Veterinary Medicines Authority (APVMA) to use S Methoprene a biological mosquito Larvicide to treat the chironomid midge Larvae in the shallow breeding areas of the lakes. Research informs the same mosquito larvicide used to reduce the emergence of adult mosquitos in the wetlands, can also reduce the chironomid midge numbers (The City advises that the only registered chironomid midge larvicide at present is A Bate (Temephos) an Organophosphate. It is not willing to use this product within the water ways, as research indicates it could in fact increase nutrient loading, among other issues in the lakes).
- Affected residents are encouraged to apply a registered residual barrier spray to the flora and hard surfaces surrounding their property to reduce the incidence of midge harbourage. Note: the use of any pesticide around your home, does have a potential risk. However, the products Coopex and Biflex are synthetic pyrethroids that are approved by the APVMA for this use. It is also recommended that we utilise whatever insect traps we have. While these efforts may seem a ‘drop in the ocean’, every bit counts.
Lake Bungana Dredging
The dredging of Lake Bungana finally commenced in early August (following initial teething problems) and is progressing well. The estimated completion time is early October, following which another treatment of Phoslock will be applied.
Some interesting observations by the dredging crew are that the sediment is up to 300mm deep and the Lake itself is up to 15 metres deep in some areas.
Note: if you watch the video, you will see the water turn black near the end of clip – this is when the suction tube reaches the bottom of the lake.