Storm Water management plan · MCU12/0133.03

Noosa Council documents


                  Bligh Tanner Consulting Engineers                                                                    Page 3
                  Noosa Flexi Learning Centre Stormwater Management Plan
                  August 2012



                  Girraween Court has existing stormwater drains and kerb and channel. The stormwater pit in
                  front of the site has an invert at RL 31.27, about 1 metre below the lowest surface level on
                  the site.
                  At the end of the existing stormwater drain is a bioretention/infiltration system which was
                  inspected and had adequate plant coverage and no evidence of impeded infiltration.


                  1.3 Proposed Land Uses
                  The site is proposed to be used as Flexible Learning Centre, which seeks to respond to the
                  needs of young people disenfranchised and disengaged from education.

                  It will consist of a series of small buildings that create a learning environment for about 80
                  young people and about 10 staff.


                  1.4 Location Conditions
                  The site is located upstream of the environmentally sensitive Noosa National Park and the
                  Girraween Nature reserve, which Burgess Creek passes through. The stormwater
                  management priorities for this area are set out in the Girraween Stormwater Management
                  Plan (Ecological Engineering 2006) as follows:
                      1. Reinstate the natural hydrology of the catchment
                      2. Repair channel incision at existing stormwater outfalls and remove invasive aquatic
                         weeds
                      3. Treat urban stormwater to current best practice standards

                  1.5 Rainfall zone
                  The nearest rainfall gauge is Noosaville (Bureau of Meteorology Station ID 040995). This
                  rainfall station commenced in 2009, and so does not provide a sufficient period of record for
                  stormwater quality modelling. Accordingly the Cooroy Composite gauge (ID 40059) has
                  been used for long term simulations in accordance with the MUSIC Modelling Guidelines
                  Version 1.0 (Water by Design 2010).


                  1.6 Soil Category
                  For the purposes of this stormwater management plan, soils have been categorised by a
                  field inspection and from the Atlas of Australian Soils (accessed via the Australian Soil
                  Resource Information System). Full soil tests will be undertaken as part of a geotechnical
                  investigation as part of the detailed design and included with the operational works
                  application.

                  The site is characterised by fine, free draining sands with modest organic material and
                  limited fines (consistent with the dunal vegetation present on site). The Soils are in zone
                  Ca10. The five dominant principle profile forms for this zone, and their typical properties, are
                  outlined in Table 2 below.

                  Table 2: Soil Properties estimated using the Atlas of Australian Soils
                  Principal      Median A horizon Texture      Median A Horizon kSat
                  profile forms (Northcote class)              (log10) (mm/hr)
                  Uc2.2          1 (Uniform Coarse)            9 +/-2
                  Uc2.3          1 (Uniform Coarse)            9 +/-2
                  Uc1.22         1 (Uniform Coarse)            9 +/-2
                  O              3 (Uniform Fine)              9 +/-2
                  Gn2.94         2 (Uniform Medium)            7 +/-2




                                                                                                   Print Date: 2 March 2020, 2:19 PM