2017-07-11 Planning & Environment Committee Agenda

PLANNING & ENVIRONMENT COMMITTEE MEETING AGENDA   11 JULY 2017




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PLANNING & ENVIRONMENT COMMITTEE MEETING AGENDA                                                     11 JULY 2017

              It is noted that current legislation and the Noosa Plan all point to Load Based Reductions
              being appropriate for urban development.       Additionally, the SEQWater Development
              Guideline effectively notes that Environmental Values for water are set under the
              Environmental Protection (Water) Policy 2009, which stipulates the appropriate targets be
              sourced from Mary River Environmental Values and Water Quality Objectives. The Mary
              River Environmental Values and Water Quality Objectives calls up the limits for Lowland
              Freshwaters (as shown in Table 2 of the Covey Report). It also critically says at Section
              3.1.3 “Stormwater Design Objectives” that design objectives for urban development are
              contained in Urban Stormwater Quality Planning Guidelines 2010. These guidelines, within
              Table 2.2, Summary of Design Objectives for Management of Stormwater Quality, again list
              the Load Based Reduction Targets (same as State Planning Policy).
              Despite the above information, it is recognised that the Lake MacDonald catchment requires
              protection from impacts associated with urban runoff, given its ecological value and use as a
              drinking water catchment. In lieu of this, it was proposed to over-treat stormwater runoff on
              site in Covey Associates Report 100415 Iss. B.
              The MUSIC modelling results from the submitted model are provided in Figure 2. The
              pollutant load reduction rates required to be demonstrated on urban and commercial
              development in South-East Queensland are as follows:
                 e   Total suspended solids (TSS) — 80% reduction in mean annual load (kg/yr)
                 e   Total Phosphorus (TP) — 60% reduction in mean annual load (kg/yr)
                 e   Total Nitrogen (TN) -45% reduction in mean annual load (kg/yr)
                                                                                             eats “anaal
                                                                                              bein

                                                       Sources      Residual Load % Reduction
                      Flow (ML/ yr)                       12-7          10.2            7.8
                      Total Suspended Solids (kg/ yr)    3420           506            85.2
                      Total Phosphorus (kg/ yr)           6.45           1.19          81.6
                      ‘Total Nitrogen (kg/ yr)            35,2           11            68.5
                      Gross Pollutants (kg/yr)           234            0.0472          100

                                                                                      | al
                       Figure 2 - Pollutant load reduction results from MUSIC Model for Report 100415 Iss. B

              The pollutant load reductions highlighted in Figure 2 are well above what is required by the
              State Planning Policy (2016) in terms of annual pollutant load reduction objectives. While
              concentration based outcomes are not generally utilised for stormwater treatment, the
              concentrations associated with a flow based sub-sample are as follows:

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