1209 SWQMP Report_3 2013

                                                                              Callaghan & Toth

3.       WATER QUALITY MANAGEMENT PLAN
3.1      Proposed On-Site Stormwater Treatment Process

The developed site was divided into MUSIC model sub-catchments as shown on Plans 02 to
04. The proposed treatment train for the development site is illustrated on Plans 02 to 04
and 09 to 11 and listed below:

1. Bioretention Swales will treat the stormwater runoff from the access roads, car parks,
    from Catchment F. The Swale is 0.6m wide at the base and will be vegetated with
    effective nutrient removal plants. The treated runoff will then be directed to vegetated
    areas within the property which eventually drain to dams which use the collected water
    for irrigation of the Avocado trees. The bio-retention component of the swales will
    remove the nutrients, heavy metals, and retard flow.

2. Grass Swales will treat the stormwater runoff from grassed areas adjacent sheds,
    Catchments C, G, GA, H, T, U and W. The Swales will be 0.6m wide at the base and will
    not be vegetated with effective nutrient removal plants.

3. Bioretention Basins will treat the stormwater runoff from bunded composting areas,
    access roads, carparks and Catchment K and N. The Bioretention Basin’s sizes for the
    site are as follows:

     • Catchment K and N Bioretention Basin will be 55m2 in area.
     • The 70m long bunded composting area Bioretention Basin will be 20m2.
     • The 120m+87m long bunded composting area Bioretention Basin will be 50m2.
     The treated runoff will then be directed to vegetated areas within the property. The bio-
     retention component of the basins will remove the nutrients, heavy metals, and retard
     flow.

4. Grass Vegetated Buffers will treat the stormwater runoff from access roads and carparks
   from Catchments A, B, D, E, I, L, M, O, P, Q, R, S, V, W1 and X. The vegetated Buffers
   will be 5m wide for the length of each catchment and flow from the catchments will be via
   sheet flow.

5. Rainwater Tanks will be required to collect water from the new shed roofs. The tanks are
    to be above ground with an overflow pipe discharging to the adjacent swales which drain
    to on site dams used for irrigation. The tank capacity is to be adequate for the part
    supply of poultry water needs and to control humidity in the sheds.

6. Sediment Basins wet coarse Sediment Basins will be required to pre-treat runoff from the
    bunded poultry litter composting areas:

     •   The sediment basin area required for the 70m long bunded composting area is 19m2
     •   The sediment basin area required for the 120+87m long bunded composting area is
         51.1m2

     Calculations for sediment basins sizing are in Appendix 8.




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1209 Animal Husbandry – Top Forestry Rd, Ridgewood                          SWQMP_REV_3
September 2013