App B - OPW Plans · MCU21/0117.02

Our Ref: 23098
Council Ref: MCU121/0117.01 & OW21/0199.01

Wednesday, 20th August 2025

Development Assessment Engineering
Noosa Council
PO Box 141
Tewantin QLD 4565
Attention: Mark Lewis
RE:      Civil Assessment for Minor Change Application
         Proposed Townhouse Development at 5 Pearl Street, Cooroy

This civil assessment has been prepared to support the proposed Minor Change Application for the
above-mentioned project, as shown in the latest Architect drawing set (Rev F), including the
proposed deck configuration within Units 6 & 8.

The proposed changes relating to stormwater quantity and quality management include:

      1. A deck extension to the Unit 6 terrace spanning across the proposed stone pitched swale;
      2. Replacement of the Unit 8 terrace with a deck spanning across the level spreader/stormwater
         discharge location;
      3. Re-configuration of the bio-retention basin resulting in an increase of the bio-retention area
         from 9m2 to 16m2.
As the proposed changes do not impact the fraction impervious or time of concentration of the site,
the proposed below ground combined rainwater/detention tank serviced by dual pumps and the
gravity emergency overflow weir/pipe are suitably sized to ensure the proposed development will not
discharge stormwater runoff greater than pre-development flow rates.

The proposed minor change will provide an increase in bioretention area and therefore will provide
an improvement of the stormwater quality outcomes. We can therefore confirm that the proposed
minor change will achieve the prescribed water quality objectives.

Please refer to the updated Siteworks and Drainage Drawing Set (drawing 23098/C10 to C22)
detailing the proposed changes relating to the stormwater management as a result of the proposed
Minor Change application.

Please contact me if you have any further queries on (07) 3369 8411.

Yours faithfully,

MORGAN CONSULTING ENGINEERS PTY LTD


Henry Morgan RPEQ 11950
Director BE MIEAust CPEng RPEQ NPER

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