Flood Investigation & Stormwater Quantity Management Plan

A: QUEENSLAND RATIONAL METHOD CALCULATIONS - CALIBRATION OF WBNM
File:        H:\B09\150-199\B09182.W\Stormwater\[B09182.W RM.xls]Calibration Model
Date:        29/10/2011
Job:         B09182.W
By:          MS
Locality:    NSC Coastal
IFD Ref:     IFD_NSC Coastal
IFD Source:  Derived from Noosa Shire Council Rainfall Intensity Curves Coastal (to Foothills) STD. DRG. 9231 (1991)Bureau of Meteorology Chart Noosa Heads (1987)
TIME OF CONCENTRATION CALCULATIONS As per Section 4.06.3 QUDM Method (c) Bushland Catchments too small to allow the formation of a creek with defined bed and banks.
                                                                                                                   Pipe
                                                                                                       Se Slope Diameter Velocity Wetted Area Wetted Perimeter
                                                                                                                                             2
Equation Type / Method                                                     Area (ha)     Length (km)      (%)      (mm)       (m/s)        (m )           (m)      Manning's n Chez's Coeff tc (min)
                                                                             9.38

Equation 4.06 QUDM - Friends Equation for Overland Sheet Flow                            0.12        7.00                                                             0.1                      36

Adopted concentrated flow velocity                                                       0.369                              1                                                                  6
                                                                                                                                                                                  Total        42

                                                                                                                                                                               Adopted tc      42      min
C10 VALUE
                                                                                     1
                              Development Category                          fi       I10 (mm/hr)                                                     C10
Enter Fraction Impervious                                                 0.00            73                                                         0.70
Table 5.04.2 QUDM
                                                                                                                                    Adopted C10      0.70

FLOW CALCULATIONS
Equation 4.01 QUDM - Queensland Rational Method
                                                                                         Adopted Time of Concentration      42
                                                                                                      tc
                                                                          ARI             Cy            Iy    A (ha)     Q (m3/s)
                                                                           2             0.60         63       9.38       0.98
                                                                           5             0.67         78       9.38       1.36
                                                                           10            0.70         88       9.38       1.61
                                                                           20            0.74        100       9.38       1.92
                                                                           50            0.81        121       9.38       2.53
                                                                          100            0.84        130       9.38       2.85