Stormwater Management Plan (Quantity)

 

The times for Dodonaea Basin to empty for different ARI events are present in Table 6 below.

Table 6: Dodonaea Basin Em Time

       

120 120 0
165 140 -25

175 140

185 140 -45

195 140 55
100 175 145 -30

In summary the Option 3 strategy incorporating new Basins B1A, B1C and the reconfiguration of the
Twigrush and Dodonaea Basins will still mitigate peak flow increases from the proposed development.
The reduction in WSL’s in the Dodonaea Basin compated to the previous sttategy is significant. ‘The
time in which the Dodonaea Basin takes to empty has also reduced.

The peak flow management strategy has been updated to achieve non-worsening objectives while the
Dodonaea Basin configuration allows for the installation of a fauna crossing under Dodonaea Close.
We trust this information is acceptable and respectfully request the new stormwater management
strategy for Lake Doonella, Noosa Stage C Development be approved.

Should you require any further information, please do not hesitate to contact Andrew McPhail ot the
undersigned on.
(07) 3895 3444.

Yours sincerely,
Brown Consulting (QLD) Pty Ltd

|

Ss \
Andrew McPhail
Principal Engineer — Water and Environment

ATTACHMENTS
1. Email from SCRC Senior Development Planner Dennis Wallace

2. Drawings
Level 6, 199 Grey Street South Brisbane QLD 4101 Australia Brown Consulting (QLD) Pty Ltd 4
PO Box 10349 Adelaide Street Brisbane QLD 4000 Australia ABN 38 109 428 506

Telephone +61 7 3895 3444 Facsimile +61 7 3895 3400 brownconsulting.com.au