RFI - stormwater report

Peak flows tabulated in this report represent the peak values extracted from the
modelled range of storm events for reporting to sub-catchment A3 (all catchments
upstream of C1) presented in Table 3-5.
Table 3-10: Regional Developed Scenario WBNM Outlet Peak Flows (A3 – Pottery Street)
                       Existing Peak Flow     Developed Peak Flow      Change in Peak Flow
                              (m3/s)                 (m3/s)                  (m3/s)
        1 year                2.149                  2.153                   0.004
        2 year               2.492                    2.493                   0.001
        5 year               3.566                    3.577                   0.011
       10 year               4.219                    4.224                   0.005
       20 year               4.911                    4.916                   0.005
       50 year               5.737                    5.737                   0.000
      100 year               6.414                    6.436                   0.022

3.1.7 Lawful Point of Discharge
Runoff from the proposed development site will be maintained south to the adjoining
properties and east to Pottery Street. A new piped outlet from the south-east of the site
will discharge the change in peak flow directly to the natural waterway approximately
100m south of the site (Figure 3-4).
The existing discharge locations and the new piped diversion are considered to be the
lawful points of discharge for the site. It is also considered that both the minor and major
flows from the site have been managed. The modeled mitigation evaluation confirms
that non-increasing in nuisance flooding from stormwater flows is achieved.




                              A01



                             Piped
                             Outlet




Figure 3-4: Lawful Point of Discharge (Source, Noosa Intramaps 2020)




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