B07056.W-01A Complete - Stormwater [As Published] · 132007.2398

Concept Stormwater Management Plan
RSL Care – Cooroy Retirement Village

                                  Table 3.5: Comparison of 100 year ARI flow rates
                               Sub-Catchment                         North                 South
                               Rational Method
                                                                2.59 – 3.02 m3/s     2.17 – 2.56 m3/s
                            Peak Discharge Range
                           DRAINS Peak Discharge
                                                                   2.91 m3/s             2.46 m3/s
                      (*Time of Concentration = 28 mins)
          * Time of Concentration for the north and south catchments are the same. However, the southern catchment
                              has a longer length of catchment despite a smaller catchment area.

The results from the DRAINS model fit well within the range of Rational Method peak discharges, therefore the
peak flows determined by DRAINS are considered appropriate.

For DRAINS model layouts and results refer to Appendix B.




B07056.W-01A.doc                                                                                               Page 7