RFI - App - Updated SWMP - 11 Robert St

                                                                   LINDSAY CONSULTING PTY LTD
                                                                                                   RAINFALL VOLUME CALCULATIONS
Project                                                                                                                                                                                                                                                   Project Number
                                                      11 ROBERT STREET, NOOSAVILLE                                                                                                                                                                        Client                                   GJ GARDNER NOOSA
                                                                                                                                                                                                                                                                                                                   240771



                                                                                                                                                                                                                          SITE INFORMATION

                                                                                                                                                                                           Total Site Area                                    1296        sqm
                                                                                     RAINFALL INTENSITIES (FROM BOM, ARR 2016)                                                             Limiting runoff from Site (Dia 450)                 999        m3/sec          (999 voids this check)
                                                                                                                                                                                           Pavement area to Detention Tank                      0         sqm
                                                                                          Annual Exceedance Probability (AEP)                                                              Storage in bio-retention basins                      0         cbm
                                                            Duration   63.20%          50%#  20%*     10%       5%          2%                                    1%                       Roof Area into Detention Tank                       512        sqm
                                                             1 min          177           199          266           311          355                    413        456                    Site Area                                          1296        sqm
                                                             2 min          151           170          231           275          319                    381        431                    Travel length                                        40        m
                                                             3 min          142           159          216           256          296                    352        396                    Site Slope                                         0.01
                                                             4 min          135           151          205           241          278                    327        365                    Surface Roughness                                   0.2
                                                             5 min          128           144          194           228          262                    306        341                    Land Description                                     L         L/M/D
                                                             10 min         105           117          157           182          207                    239        264                    Soil Permeability                                    H         High/Medium/Low (H/M/L)
                                                             15 min           89          99.7         132           154          175                    202        222                    L ==> Light cover bushland, or poor grass cover, or low density pasture, or low cover bare fallows
                                                             30 min         62.8          70.3           94          110          125                    146        161                    M ==> Medium Density Bush, or good grass cover, or high density pasture, or zero tilling cropping
                                                             1 hour         41.6          46.8         63.5            75         86.5                   102        114                    H ==> Dense Bushland
                                                             2 hour         26.7          30.3           42          50.3         58.7                   70.2       79.4                   Un-Developed Fraction Impervious                    0.4                        From Fig. 4.05.1 in QUDM (2007)
                                                             3 hour         20.6          23.5           33          39.8         46.7                   56.3       63.9                   Developed Fraction Impervious                        1                         From Fig. 4.05.1 in QUDM (2007)
                                                             6 hour         13.3          15.3           22          26.8         31.7                   38.4       43.7                   One Hr rainfall Intensity for Q10                         75 mm/hr
                                                             12 hour        8.64          10.1         14.7            18         21.4                   26.1       29.7                   Calculated Travel Time                               11        Min             Must equal time selected for intensity
                                                             24 hour        5.63          6.58         9.73            12         14.3                   17.5        20                    Adopted Storm Time                                   10        min
                                                             48 hour        3.57          4.18          6.2          7.65         9.15                   11.4       13.2
                                                             72 hour        2.68          3.13         4.64          5.74         6.88                   8.62       10.1                   Detention Tank Provided                           10000        lt




                                                                                                                                                 Average Expected Return Interval (AER)
                                                                                63%                        50%                               20%                    10%                                5%                              2%                             1%
          Intensity (for Return Interval)                                      105.00                     117.00                            157.00                 182.00                            207.00                          239.00                         264.00
                                                                       Undeveloped     Developed   Undeveloped    Developed   Undeveloped          Developed    Undeveloped    Developed    Undeveloped      Developed     Undeveloped       Developed     Undeveloped      Developed
          C10 value                                                      0.780          0.900        0.780         0.900        0.780               0.900         0.780         0.900         0.780           0.900           0.780           0.900            0.780         0.900
          Fy Factor                                                      0.800          0.800        0.850         0.850        0.950               0.950         1.000         1.000         1.050           1.050           1.150           1.150            1.200         1.200
          Cy                                                             0.624          0.720        0.663         0.765        0.741               0.855         0.780         0.900         0.819           0.945           0.897           1.035            0.936         1.080
          Q (m3/sec)                                                     0.024          0.027        0.028         0.032        0.042               0.048         0.051         0.059         0.061           0.070           0.077           0.089            0.089         0.103
          Total Rainfall for event (m3)                                          17                          20                               30                          36                            43                              54                             62
          Total Non-Worsening Volume for Storm (m3)                               3                          3                                 4                           5                             6                               8                              9
          Roof Area Runoff for Storm (m3)                                         6                          7                                11                          13                            16                              21                             24


                                                                                                                              SQUARE EDGE ORIFICE CALCULATION
                                                                                                                                      Q             59.01517
                                                                                                                                      C                   0.6
                                                                                                                                      g                  9.81
                                                                                                                                             h                        0.8                  Height from orifice centre line to water level
                                                                                                                                             A                  0.024827
                                                                                                                                             Dia                177.7927                   required diameter