Development Application - Part 2 of 2 - Report & Plans · OPW11/0116

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Figure 3: EPA aerial photos of Noosa River configurations -1991 [calm weather] and 1992 [post Cyclone Betsy]

In 2006, Chamberlain & Tomlinson published a technical paper on Noosa River entrance channel dynamics based on a
review of historic aerial photographs. As part of the proposed works, this analysis was extended to the present date [for full
report, see Appendix A).

Noosa River Spit in the Noosa estuary has suffered erosion for many years. In 2003, dredging works within the river allowed
for nourishment along the Noosa River Spit foreshore and the establishment of sand bunds to artificially close the dominant
southern channel [Figure 41. These sand bunds were very effective in the short-term, reducing erosion and creating a calm
lagoon area. The channel velocities resulted in erosion and breaching of the bunds, requiring annual dredging works to
maintain these structures. The costs associated with regular dredging and the limitations placed on the dredging due to the
proximity of the Noosa River Fish Habitat Area made regular ongoing dredging undesirable. As a result, the last "top-up" of
the bunds was completed in 2005.




Figure 4: SCRC aerial showing sand pumping to keep channel off the Noosa River Spit [2003]

In 2006, erosion was once again a significant issue and a review of erosion management options for Noosa River Spit was
undertaken by International Coastal Management [ICM]. A number of options were considered, including:

    A.   Do Nothing.
    B.   Establish erosion limit control lines.
    C.   Stabilise present channel location and beach:
         C1.       Walls along severely eroding sections.
         C2.       Walls, groynes & low training walls.
    D.   Relocate main channel away from the Noosa River Spit:
         D1.       Ongoing dredging.
         D2.       Fluidiser.