Stormwater Management Plan · MCU15/0122

                                                                                 15099 - SBSMP/2
                                                                                          Page 8




5 STORMWATER QUANTITY
A roof and allotment drainage system is to be designed to comply with:
    1. AS/NZS 3500.3:2003 - Plumbing and Drainage Part 3: Stormwater Drainage;
    2. the Queensland Urban Drainage Manual (QUDM);
    3. The Noosa Council Planning Scheme


5.1 Design Storms
As defined in Noosa Council’s Planning Scheme the following design storms were adopted:
    1. Minor Drainage System: 10 year ARI statistical flood (Q10 storm), and;
    2. Major Drainage System: 100 year ARI statistical flood (Q100 storm).


5.2 Rainfall Intensity
Rainfall intensities for this study were obtained from the IFD chart for the Noosa Region
calculated from AR&R, 1987 and sourced from the Australian Bureau of Meteorology.


5.3 Times of Concentration
Times of concentration (tc) were calculated as defined Section 4.06 of the QUDM. Refer to
Table 5-1 for the adopted tc’s and Appendix F for tc calculations.

                                      Table 5-1 – Adopted tc values
                                   Pre Development        Post Development
                                       tc (mins)               tc (mins)

                                          8.9                    5.0



5.4 Runoff Coefficients
The 10 year runoff coefficient’s (C10) were determined as defined in Section 4.05 of the QUDM.
Refer to Table 5-2 below for the adopted C10 values.

                                      Table 5-2 – Adopted C10 Values

                                         Property State                C10

                                       Pre-development                 0.74
                                       Post-development                0.86




Site Based Stormwater Management Plan
Proposed Medical Development at Cnr Val Crescent & Goodchap Street, Noosaville