2021-12-07 Planning & Environment Committee Meeting Agenda - Updated

PLANNING & ENVIRONMENT COMMITTEE MEETING AGENDA                                 7 DECEMBER 2021


Attachment 2
Technical Evaluation of Proposed Water Quality Objectives.
Datasets send by DES on 5 November were used for direct comparison of the 2004 low and high percentile values against parameters.
In the column Proposed Objectives, red numbers show the proposed objectives are worse than the 2004 data, and green show they are better. 2010
WQO’s are provided in the Constituent column and coursed red or green to identify the direction the proposed WQO’s deviate, red less stringent, green
more stringent, black no change. The following criteria was used to inform the final comment:
Where the new proposed objectives based on all available water quality data are:
       More stringent than historical data up to 2004 for the equivalent Low or High low splits and more stringent than 2010 WQO’s they are supported
        as understand more relevant to Noosa’s natural environment than the Tasmanian objectives.
       Less stringent than the historical data up to 2004 for the equivalent Low or High low splits, but more stringent than the 2010 objectives, then our
        request is that the new objectives are based on relevant percentiles for historical data up to 2004, this is to facilitate no worsening over time.
       More stringent than the historical data up to 2004 for the equivalent Low or High low splits, but less stringent than the 2010 objectives, by 1
        standard deviation of the long-term data, concerns are raised, and consideration given to keep objectives in 2010 WQOs.
       Less stringent than 2010 objectives by more than two standard deviations, concerns are raised, and consideration given to maintaining the 2010
        objectives until the need for the change can be attributed to something in the existing environment that cannot be changed or better managed.
        For example, as outlined in the comments for Burgess Creek.

    Water             Constituent          Original WQ Data to     Proposed              Comment
                                           2004                    Objectives
                                           20,50,80 %iles          20,50,80 %iles
    Lake Cootharaba   Total Phosphorous    Low 13,21,26            11, 17, 25            Low flows are an improvement of the situation from 2004. For
    Section 1         2010 WQO’s           High 10,18,25           12, 17, 25            high flows, only the 50th%ile high flow improves. None of the
                      (10,15,20)                                                         objectives are equivalent or improving on the 2010 WQO’s.
                                                                                         Needs to confirm this phosphorous is not related to the need to
                                                                                         better manage effluent in this area prior to endorsement.

                                                                                         Where attributed to a management action, request for 2010
                                                                                         WQO to be maintained.
                                                                                         Where unable be attributed to a feasible management action,
                                                                                         only 2021 low flow objectives, and 2004 high flow objectives
                                                                                         could be supported.

                      Turbidity            Low 13,18,28.6          13, 20, 40            Proposed objectives endorse worsening and cannot be
                                           High 14, 27, 54         17, 30, 55            supported.

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