132004.240018.A - Request to change an existing Approval

                                     SMEC

Levell,                        Building C, 6 Innovation        Parkway
Birtinya,                      OLD 4575, Australia
(PO Box 179, Buddina,                          OLD 4575, Australia)
T +61 7 3029 6700 F +61 7 5437 6525 E [email protected]
www.smec.com



19 August                        2014


Noosa Council
Po Box 141
TEWANTIN OLD 4565


Attention:                       Mark Lewis,


RE: Changes To Existing Approval                                  Conditions.             OPW 12/0339

Further to our meeting with Council on 31 July 2014, on behalf of our client PEEl Limited, SMEC seek approval
from Council to amend Condition 65.1.2 of Application No. 132004.240018.6 (23689 DA).

This condition relates to the upgrading of Garnet Street to enable fiood free access to the site during a 1 in 10
year Average Recurrence Interval (ARI) flood event and trafficable access in a 1 in 100 year ARI fiood event

Further to the previously provided Hydrology and Water report (2014) titled "Garnet Street Culvert Upgrade
Hydraulic Assessment" the information below is provided to support the application to amend the current
conditions of approval.

Constraints associated with compliance with Current Approval Conditions

The current approval conditions in relation to the Greenwood Grove estate require the upgrade of Garnet
Street (Cooroy Creek crossing) to provide full immunity in a 10% Annual Exceedance Probability (AEP) rainfall
event and be safely trafficable during the 1% AEP rainfall event.

After detailed modelling and consideration of road geometry and drainage eiements, the following constraints
limit the ability to achieve compliance with the condition:-

1.             Garnet Street in its existing formation provides flood mitigation. Alteration of road levels and pipe culvert
               configuration must ensure non-worsening both upstream and downstream of Garnet street.

2.             The ability to raise Garnet Street in combination                              with increased culverts to achieve the desired immunity
               has limitations           in the form of:-

                           a.     Maintaining the sag point at Cooroy Creek;

                           b.     Earthworks / embankment              extents to be maintained                    within the road reserve;

                           c.     Close proximity of Cooroy Creek immediately adjacent to the road reserve(bend upstream)

                           d.     Changing existing overland flow paths and

                           e.     Impact on adjoining private properties.

The most recent design (Refer updated Civil Drawings) proposes to raise Garnet Street to what is considered to
be the malCimum levels without changing or elCceeding the above mentioned limitations.

Given these constraints and limitations, configuration                                        and sizing of culverts has been determined                   to limit non-
worsening of upstream and downstream conditions.




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