000A88A4.12D.tif · 132003.221037

& Cardno
MABK
Water levels in the lake were also reviewed. It was found that the maximum and minimum water
levels in the lake were maintained within plus 0.3m and minus 0.4m of the outlet weir level. This
indicates that, provided infiltration gains or losses are minimal, there is sufficient runoff from the
development to maintain a functional body of water within the lake. The appropriate spillway

configuration that minimises potential impacts fromm concentrated flows will be determined at
detailed design stage. :

7.56 Conclusions

The potential impacts of the proposed development were assessed using AQUALM with
established input parameters. The AQUALM analysis indicated that the expected pollutant
exports from the proposed development can be reduced to sustainable loads by the
implementation of appropriate stormwater quality treatment measures. These measures
comprise the use of filter strips/swales in the East Visitor Precinct and the use of bio-retention
systems followed by treatment within the proposed lake at the West Visitor Precinct.

The AQUALM analysis also indicated that there is sufficient runoff from the West Visitor to
maintain a functional body of water within the lake, provided infiltration losses are minimal.

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PETRAS LAND HOLDINGS P/L Neosa North Shore Eco-Tourism Portai September 2003
LA7298-03\Repor\FINAL REPORT - 18Sept03.doc Commerciai in Confidence Page 25