Attachment 1 - RECOR RFI Cover Letter Response_20210216

DRAINS Modelling Results - Full Catchment
Project number:     20210216                                                                    Calculations:           B. Parry
Street Address:     62 Gateway Drive
Locality:           Noosaville, NSC                                                             Date:                   26/09/2022



Catchment Post-development Validation (10 min Tc)
                              3                   3
                    Qy Post (m /s) OPW Qy Post (m /s)
                                                                              3
A.E.P               2007/1625              DRAINS                     Qdiff (m /s)              Qdiff (%)
          63.2% AEP N/A                                       1.170 N/A                         N/A
              0.5 EY                    1.660                 1.470                    -0.190                   -11%
              0.2 EY                    2.090                 1.880                    -0.210                   -10%
            10% AEP                     2.390                 2.190                    -0.200                    -8%
             5% AEP                     2.720                 2.530                    -0.190                    -7%
             2% AEP                     2.880                 2.930                     0.050                     2%
             1% AEP                     3.180                 3.220                     0.040                     1%

Catchment Post-development OSD Validation (10 min Tc)
                                  3
                    Qy Post OSD (m /s)    Qy Post OSD
                                                  3                           3
A.E.P                  OPW 2007/1625            (m /s) DRAINS         Qdiff (m /s)              Qdiff (%)
          63.2% AEP N/A                                       0.373 N/A                         N/A
              0.5 EY                    0.450                 0.443                    -0.007                    -2%
              0.2 EY                    0.510                 0.540                     0.030                     6%
            10% AEP                     0.620                 0.663                     0.043                     7%
             5% AEP                     0.840                 0.925                     0.085                    10%
             2% AEP                     1.100                 1.131                     0.031                     3%
             1% AEP                     1.370                 1.378                     0.008                     1%

Catchment Post w/ OSD Comparison
                       Qy Post                  Qy Post 2100
                                                          3                       3
A.E.P                  2100 (m3/s)              OSD (m /s)            Qchange (m /s)            Qchange (%)             Basin Depth (m)
          63.2% AEP                     1.170                 0.373                    -0.797                   -68%                  0.659
              0.5 EY                    1.470                 0.443                    -1.027                   -70%                  0.863
              0.2 EY                    1.880                 0.540                    -1.340                   -71%                  1.129
            10% AEP                     2.190                 0.663                    -1.527                   -70%                  1.206
             5% AEP                     2.530                 0.925                    -1.605                   -63%                  1.318
             2% AEP                     2.930                 1.131                    -1.799                   -61%                  1.391
             1% AEP                     3.220                 1.378                    -1.842                   -57%                  1.468

Catchment Q2100 Post Development
                                                Qy Post
                                                          3                       3
A.E.P                  Qy Post (m3/s)           2100 (m /s)           Qchange (m /s)            Qchange (%)
          63.2% AEP                     1.170                 1.410                    0.240                    20.5%
              0.5 EY                    1.470                 1.780                    0.310                    21.1%
              0.2 EY                    1.880                 2.280                    0.400                    21.3%
            10% AEP                     2.190                 2.660                    0.470                    21.5%
             5% AEP                     2.530                 3.060                    0.530                    20.9%
             2% AEP                     2.930                 3.540                    0.610                    20.8%
             1% AEP                     3.220                 3.880                    0.660                    20.5%

Catchment Post 2100 w/ OSD Comparison
                       Qy Post                  Qy Post 2100
                                                          3                       3
A.E.P                  2100 (m3/s)              OSD (m /s)            Qchange (m /s)            Qchange (%)             Basin Depth (m)
          63.2% AEP                     1.410                 0.415                    -0.995                   -71%                  0.778
              0.5 EY                    1.780                 0.498                    -1.282                   -72%                  1.041
              0.2 EY                    2.280                 0.767                    -1.513                   -66%                  1.255
            10% AEP                     2.660                 0.960                    -1.700                   -64%                  1.331
             5% AEP                     3.060                 1.249                    -1.811                   -59%                  1.429
             2% AEP                     3.540                 1.532                    -2.008                   -57%                  1.513
             1% AEP                     3.880                 1.724                    -2.156                   -56%                  1.567