Hydraulic Assessment 29 August 2024

1. INTRODUCTION
Engeny Australia Pty Ltd (Engeny) have been engaged by Mark Kussrow to prepare a Hydraulic Assessment to support development works
at 38 Barina Court, Pomona (the Site). The Site is located within the Noosa Council (NC) Local Government Authority (LGA) area.

The Reconfiguring A Lot (RAL) was approved by NC on the 24th April 2024 (application no: RAL22/0034). This hydraulic assessment has been
prepared to address items within:

•   Condition 25 of the Decision, which requires all works to be carried out in accordance with the recommendations in Section 5 of Tectonic’s
    Geotechnical Investigation of Existing Dam Report (22244-002-Rev1) dated 26 February 2024, which states:

    –   A civil/hydraulic RPEQ must complete an assessment of the catchment hydrology and anticipated flows. Subject to the results of the
        civil/hydraulic assessment, the existing spillway may need to be upgraded to ensure that a minimum freeboard of 1 m is maintained
        beneath the embankment crest, thus preventing water overtopping the embankment including during flood events.

    –   Depending on the civil/hydraulic assessment and the anticipated stormwater flows, the existing channel along the embankment toe
        may also require upgrades to accommodate future flows during flood events. Stormwater flows must not be allowed to overtop the
        dam embankment crest or associated discharge channels.

    –   Areas exhibiting existing erosion scours within the main spillway discharge channel must be reinstated and protected from future
        erosion. The erosion protection required will be dependent on the anticipated stormwater flows which are to be determined by
        hydraulic analysis by a civil/hydraulic RPEQ. An indicative specification for rock fill is provided below, however the necessary grading
        for the rock fill should be assessed by a hydraulic or civil RPEQ prior considering anticipated stormwater velocities.
Condition 16 also requires any upgrade works associated with the dam to be undertaken in accordance with an Operational Works approval.
This report will provide the guidance for any upgrades which will be detailed and completed by others.


1.1         Site Characteristics
The Site has an approximate area of 6.4 ha, has narrow frontage to Barina Court in the north-eastern corner, and direct frontages to Pomona
Connection Road and Cooroy-Gympie Road (Old Bruce Highway) along the western and southern boundaries, respectively. The existing dam
is located within the north-eastern corner of the Site, with the main dam along the western boundary.

The geotechnical investigation has identified the dam construction took place between 1986 and 1993. The location of the Site is shown in
Figure 1.1 below, while detailed survey is provided in Appendix A.




FIGURE 1.1: SITE LOCALITY


38 BARINA COURT, POMONA I BBNE00000_0020-REP-001-0                                                                                            1