Attachment 5A - Noosa Landfill RRA Flood Assessment

Noosa Landfill RRA Flood Assessment


3.5       Design Rainfall
Design rainfall has been applied to the model using direct rainfall on grid. ARR2019 ensemble
temporal patterns have been applied to the model for a range of duration events and then peak
flood characteristics have been selected at each cell based on the critical duration and the
associated median ensemble pattern. This process is undertaken using TUFLOW result
processing tools and is undertaken for each individual cell in the model. This methodology is in
accordance with the latest ARR2019 guidelines.

Modelling has been undertaken for events with durations of 30, 60, 120 and 180 minutes.

Modelling has been carried out for the following design event probabilities for the base case and
proposed case modelling:

      •    50% AEP (Q2)
      •    10% AEP (Q10)
      •    1% AEP Current Climate (Q100)
      •    1% AEP Year 2100 Climate

The following ‘rare’ events have also been simulated for the proposed case:

      •    0.5% AEP (Q200)
      •    0.2% AEP (Q500)
      •    0.1% AEP (Q1000)

The latest available design rainfall intensity data has been taken from the Bureau of Meteorology
(BoM) IFD website.




J00352R1V2                                                                                    6