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

PLANNING & ENVIRONMENT COMMITTEE MEETING AGENDA                            7 DECEMBER 2021


Water         Constituent         Original WQ Data to      Proposed              Comment
                                  2004                     Objectives
                                  20,50,80 %iles           20,50,80 %iles
                                                                                 High flows are an improvement of the situation from 2004 and
                                                                                 can be supported.
              Turbidity           Low: 7,11,14             Low:7, 10, 17         Proposed objectives endorse worsening and cannot be
              (2, 5, 8)           High:9, 14, 31           High: 10, 16, 30      supported. Recommend maintaining the 2004 quality here.
Lake Weyba    Total Nitrogen      LWMid          Estuary   Low:280, 340, 430     For Lowflows: Proposed objectives endorse worsening and
              (Low flows: 150,    Low:160, 185, 268        High:280, 410, 520    cannot be supported. Lake Weyba receives runoff from the
              240, 380)           LWMid          Estuary                         industrial area. An evaluation of water quality management
                                  High:50th%ile = 460                            opportunities where no management opportunities exist 2004
                                                                                 quality is supported here.

                                                                                 For Highflow: No 2010 WQO for highflow. The proposed
                                                                                 50th%ile of 410 is better than 2004 data and is supported.
              Oxidised Nitrogen   LWMid        Estuary     Low:1, 1, 5           Improvement of the situation and can be supported.
              (2,5,15)            Low:1,3,8                High:1, 9, 35         High flow criteria were not previously outlined in 2010 WQO.
                                  LWMid Estuary High:
                                  50th%ile =17
              Ammonia             LWMid Estuary Low:       Low: 4,12,40          Proposed objectives endorse worsening and cannot be
              (HEV 7,15,32)       2, 8, 17                 High:7, 20, 120       supported.
              (SD 32)             LWMid Estuary High:
                                  50th%ile =33                                   2004 data specific for Lake Weyba was not available to
                                                                                 interrogate for comparison.     These values are relevant
                                                                                 because, while there is substantial groundwater monitoring at
                                                                                 the landfill to ensure no releases, Ammonia is an indicator
                                                                                 whether Leachate from the landfill, which flows to Lake Weyba
                                                                                 is escaping.

                                                                                 Preference is to compare the proposed objectives to the 2004
                                                                                 data for Lake Weyba, if available, and select best from there?
              Turbidity           LWMid Estuary Low:       Low: 4, 8, 17         Proposed objectives endorse worsening and cannot be
              (HEV =2,5,8)        1, 2, 4                  High:4, 7, 19         supported.
              (SD=8)              LWMid Estuary High:
                                  50th%ile =3                                    2004 data specific for Lake Weyba was not available to
                                                                                 interrogate for comparison.




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