080624 2383-01 FINAL Engineering Report for DA.pdf [As Published] · 132008.1128

BLUE CARE SUNRISE BEACH
ENGINEERING REPORT FOR DEVELOPMENT APPLICATION



    3.2.2          Sewerage

    Average Dry Weather Flow (ADWF) = 600 L/ET/day

    Occupancy Ratio = 3.3 Equivalent People/Detached Dwelling = 3.3 EP/ET

    Peak Wet Weather Flow (PWWF) = 5 * ADWF = 3000 L/ET/day

    Table 3.3, Maximum Possible Flow (L/s)
        GRADE            150DIA           225DIA    300DIA
          420                                         43
          400                                         44
          350                                         47
          300                                         51
          290                                  24
          250                                  26     55
          200                                  29     62
          150               11                 33     71
          125               12                 36     78
          100               14                 41     27
           75               16                 47    101
           50               19                 57    124



    Table 3.4, Minimum Allowable Flows (ET)
       PIPE DIA (mm)             MINIMUM            MINIMUM           MINIMUM No OF   MINIMUM PUMPED
                                 GRADE              DEPTH OF          TENEMENTS       FLOW L/S
                                                    FLOW (mm)


        150                       1 in 150                 25                 4               2
         225                       1 in 290                40               170               5
         300                       1 in 420                50               270               8
         375                       1 in 570                70               530              15
         450                       1 in 730                80               690              19
         525                       1 in 900                95               970              27
         600                       1 in 1000               110              1360             36


    Sewer Easements
    Easements shall be equivalent in total width to twice the depth to invert level of sewer at
    the deepest point within the allotment. The minimum setback distance from the
    centreline of the sewer shall be 1.5m regardless of the depth of the sewer main.
    Easements are to be parallel to, and centred over, sewer lines.

    Zone of Influence
    It shall not be permitted to construct sewers in new subdivisions or developments
    whereby adjacent established buildings or existing building envelopes encroach into the
    zone of influence of the new sewer. The zone of influence shall be taken as that area
    within a 45o angle from invert level of the sewer.

    Scour Velocity
    The mains shall be sized such that minimum scour velocity is 0.75m/s in the pressure
    main at maximum head (single pump) and maximum scour velocity is 1.8m/s (double
    pump) at minimum head, ie. well full.




Blue Care Property Development Unit                             Version 1.1                            24 June 2008
2008 06 24 2383-01 Engineering Report for DA               Commercial in Confidence                         Page 15