13. Appendix I - Integrated Water Mangement Plan

                                                                                 Integrated Water Management Plan
                                                                         Noosa Marketplace : 2-20 HOFMANN DRIVE



                 Rational Method Verification
 Parameter                                       Value
                                     Catchment 2    Catchment 3
 C10                                      0.70           0.70
 tc (min)                                10.68           9.07
 I (1yr,10min)                            102            102
 A (ha)                                   0.77           0.60
 Rational Method Flow (m3/s)              0.46           0.38
 RAFTS Peak Flow (m3/s)                   0.74           0.58
 Difference (m3/s)                        0.29           0.20

3.2.5       Results
Peak flows for each of the sub catchments are listed in Table 3-4 for the 1% AEP event. The critical storm
duration for 1%, 2% and 5% AEP events was determined to be 15 minutes, while, for the 39% and 20% AEP
events, the times of concentration was 25 minutes. For the 10% AEP event, the time of concentration was 20
minutes. This difference in time of concentration was considered to be typical for models run with ARR 2016
rainfall patterns. In addition to the peak flows coming from each catchment, the peak total flow from the site
was found to be 1.84 m3/s in the 1% AEP event.




V190428 | 15 May 2019 | Commercial in Confidence                                                               9