F0002-AA007595-AAR-10-SMP · MCU14/0102.05

                  INTERNAL CATCHMENT ASSESSMENT
                  TEMPORAL PATTERNS
                  Rainfall data and information from the Australian Bureau of Meteorology was utilised to
                  generate the design storm event hydrographs for the stormwater run-off. Intensity-Frequency-
                  Distribution (IFD) charts and tables for the specific subject site are presented in Appendix D.


                  LEGAL POINT OF DISCHARGE
                  The subject site currently contains three internal catchments which discharge flows into three
                  separate locations.

                        - At the southern border of the site, there is a 600mmx600mm field inlet pit, which collects
                          flows and discharges to a 300mm diameter stormwater pipe within the Lionel Donovan
                          Drive road reserve.

                        - There are two field inlets located within the kerb and channel along Eumundi Noosa
                          Road, which collect flows from Lot 4SP159610. These pits discharge into a 675mm
                          diameter pipe within the Eumundi Noosa Road road reserve. These pipes flow to the
                          north toward Lake Doonella and the Noosa River.

                        - There is also a 225mm diameter pipe within the existing drainage easement of Lot
                          31SP170751. This then increases to a 300mm diameter stormwater pipe in the adjacent
                          lot to the east. At the junction of these pipes is a 600mmx900mm field inlet, which collects
                          overland flow from Lot 31SP10751.

                  The internal catchments are illustrated in the engineering drawings in Appendix B.


                   CATCHMENTS
                  The site has three internal catchments. Details of these catchments are provided in Hyder
                  Drawings SK01300-AA007595-01.


                   CATCHMENT 1 DISCHARGE
                  Catchment 1 is a small internal catchment at the south of Lot 4 on SP159610. In its existing
                  state, the catchment area is used for commercial and automative purposes.
                  Table 4.1, below, lists the catchment characteristics for the site.
                                                    Table 4.1 – Peak discharge flow rates comparison

                              PARAMETERS                                      EXISTING                 DEVELOPED

                       Approx. Developed Area                                     0.10                      0.09

                           Fraction Impervious                                    0.85                      0.85

                      Coefficient of Runoff (C10)                                 0.87                      0.87

                      Coefficient of Runoff (C50)                                   1                        1

                         Time of Concentration                                5 minutes                   5 minutes

139 Eumundi Noosa Road & 30 Lionel Donovan Drive, Noosaville Service Station and Retail Site—Stormwater
Management Plans
Hyder Consulting Pty Ltd-ABN 76 104 485 289                                                                           5
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