16-001014-02A (Ultimate SCMMP)

2.3.2     MOSQUITOES

In a well‐designed and managed WQCP mosquitoes are rarely a problem and in most cases community education is part
of the solution. Residents should be encouraged to eliminate mosquito breeding sites by eliminating stagnant pools of water
formed by containers, pot plants, etc.
The creation of diverse habitats, that support predatory insects, minimisation of areas for mosquito larvae to hide,
maintenance of flow through the constructed WQCP, avoidance of small puddles, algae build up on structures and
control over water levels are the main mosquito management strategies.
Checks should also be undertaken for the presence of mosquito fish. While mosquito fish are effective for controlling
mosquito larvaue, some species (i.e. Gambusia spp.) may adversely impact frog and native fish populations. Coppock
and Erskine (1997) have found that native Fire‐tailed Gudgeons (Hypseleotris galii) are successful predators of mosquito
larvae and should be seeded into the pond before Gambusia can establish. Their introduction into a constructed WQCP
is only viable if a reasonable quality of oxygenated water can be established.

Insectivorous birds should be encouraged to keep control over adult mosquito populations.
Maintenance staff should check for the presence of mosquito larvae in shallow pooled water at the edge of the
constructed WQCP. A key performance indicator during the Operational Phase is 1 larvae per 2 ladles dips
(300mL ladle).
Corrective actions shall be consistent with the most current versions of the “Water by Design – Rectifying Stormwater
Assets”. Removal of litter (that can create habitats for mosquitoes) and isolated pools of water through filling and/or
profiling are immediate corrective actions that should be undertaken if a mosquito habitat is identified. If the problem
persists, Page 53 of the “Water by Design – Rectifying Stormwater Assets” indicates further corrective actions. An extract
is provided in Appendix A. Some of these involve consultation with a mosquito specialist, checking that WQCP ponding
depths is in accordance with design details and introducing predators of mosquitoes.

2.3.3     CYANOBACTERIAL BLOOMS

Performance indicators for managing cyanobacterial blooms during Operational Phase includes:
 No fertiliser to be used on the banks of the pond or WQCP;
 Schedule and measure any fertiliser applications to maximise nutrient uptake by plants and avoid runoff throughout
   upstream catchment;
 Water is clear, that is turbidity is such that the floor of the pond can be seen at 0.75m depth;
 No visible algal blooms;
 No floating declared or environmental weeds present; and
 Macrophyte coverage to be above 15% of the WQCP water surface. Inspections shall also assess unhealthy
   plants or dieback.

If inspections reveal non-performance of indicators (as indicated above in bolded italics), water quality testing is
required to assess the potential of Cyanobacteria Blooms and need for corrective actions. Macrophyte coverage and
dieback rates that trigger the requirement for water quality testing are to be regularly reviewed and updated as per the
latest peer reviewed journal specifications. Yearly assessment of performance indicators is to be undertaken. This is in
accordance with Item 2(a) of Council’s Operational Works - Bulk Earthworks Decision Notice (dated 15 October 2015).

Performance indicator for water quality testing is ≤500cells/mL Microcystis aeruginosa or biovolume equivalent ≤0.04
mm3/mL combined total of all cyanobacteria. Further details on the response to trigger levels for cyanobacteria blooms
can be found in Appendix A and includes notification and signage for higher algal counts, as based on the Queensland
Water Quality Guidelines 2009 and the NH&MRC Guidelines for Managing Risk in Recreational Water (2008). Trigger
levels are to be regularly reviewed and updated in accordance with the latest relevant health regulations. Yearly
assessment of required performance targets is to be undertaken. This is in accordance with Item 2(b) of Council’s
Operational Works - Bulk Earthworks Decision Notice (dated 15 October 2015).

Corrective actions shall be consistent with the most current versions of the “Water by Design – Rectifying Stormwater
Assets”. Page 58 of the “Water by Design – Rectifying Stormwater Assets” indicates corrective actions that may be




16-001014-02A | SMCMP | PALM LAKE RESORTS                        COOROY RETIREMENT COMMUNITY, TRADING POST
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