SWMP change reps

The Developed site catchments are as follows.

Catchment A

    -     Area – 0.4363 Ha
    -     Tc – 6 mins
    -     Fraction Impervious (Fi) – 0.77

Catchment B

    -     Area – 0.1955 Ha
    -     Tc – 6 mins
    -     Fraction Impervious (Fi) – 0.83
    -



Peak flow rates for the median design storms for the developed site are given in Table 6.4

                            Table 6.4 – Developed Site Peak Flow Rates (L/s) (At year 2100)

   Storm Event           Q1            Q2           Q5             Q10           Q20            Q50       Q100
                        (1EY)        (0.5EY)      (0.2EY)      (10%AEP)       (5%AEP)         (2%AEP)   (1%AEP)

         Cat A           124          156           193            233           270            321        359
  Developed PFR

         Cat B             60          75           93             111           129            149        166
  Developed PFR

(PFR – Peak Flow Rate)



6.1.4      Peak Flow Comparison
Table 6.5 indicates the increased peak flow rates for the developed cases.

                    Table 6.5 – Comparison of Existing Vs Developed Peak Flows (L/s) (At year 2100)

        AEP Storm               Q1      Q2         Q5           Q10           Q20             Q50       Q100
                           (1EY)      (0.5EY)   (0.2EY)     (10%AEP)       (5%AEP) (2%AEP) (1%AEP)

            Cat A               45      37         33           47             52             62        72
        Increase PFR
            Cat B               33      36         41           52             60             66        75
        Increase PFR
   (PFR – Peak Flow Rate )

SCG Consulting Engineers                        Page 18                                SCG Ref: 33132(SWMP).RevC