Noosa River DMP V1

Dugongs have poorly developed eyesight and rely on bristles on their upper lip, rather than visual cues, to detect
seagrass food resources. Flatback Turtles are known to feed in turbid shallow waters and may not be directly
affected by turbid plumes generated by dredging. Other marine turtle species such as Green and Hawksbill Turtle,
which feed on seagrass and/or in reef environments, may avoid areas affected by turbid plumes.
It is expected that marine fauna will avoid the source of underwater noise and their immediate surrounds. Once
operations have been completed, avoidance behaviour is expected to cease.
Objective: To minimise risk of impact of dredging and nourishment works on flora and fauna.
Issues: Injury to marine fauna from vessel strike or dredger operations.
Performance Criteria: No injury to marine mega-fauna. No impact to marine plants except where approved.
Control Measures:

                                                                                                                     Responsible
                                                  Control Measures
                                                                                                                        Party
 1.   Beach renourishment is not to cover any exposed mangrove pneumatophores. Marine plants survey to be          Contractor
      undertaken prior to dredging works and tree protection zone to be pegged out when necessary to avoid
      impacts (including when exposed pneumatophores are identified).
 2.   Seagrasses not to be impacted during dredging.                                                               Contractor
 3.   Beach renourishment is to be undertaken in a manner that does not damage the root systems of any             Contractor
      undermined trees that are not mangroves. No buffer needs to be observed where there is an expectation
      that nourishment will enhance stability.
 4.   Water quality monitoring to be undertaken in accordance with Table 4. Water quality to be managed in         Contractor
      accordance with control measures in section 5.1
 5.   Visual observations shall be undertaken for at least 10 minutes prior to commencement of dredging            Contractor
      operations and periodically throughout works. Should fauna be observed, operations shall cease until the
      spotted animal has moved on.
 6.   In the event that a marine animal is captured or injured during the course of dredging, DES is to be         Contractor
      notified (phone 1300 130 372). The incident is to be recorded in the dredge log.
 7.   No extraction or replenishment activities should be undertaken during the closed seasons for important fin   Contractor
      fish species likely to occur in the Noosa River (specifically, July to August)
 8.   Extraction should not be undertaken more frequently than every two years from the same site to allow         Contractor
      time for benthic community recovery between events;
 9.   Material should be deposited on the receiving site in a spray of sand and water or in a number of shallow    Contractor
      layers (e.g. up to 20cm depth per layer) to maximise survival and vertical migration by resident infauna.


Monitoring: Monitoring is to be undertaken in accordance with Table 4.


            LAND
Geotechnical investigations have been undertaken by Soil Survey (2006), BMT (2022) and Pacific Geotech
(2023) (section 4.1.2).



21