13. Existing DMP (2006)

2.12 Quantity of materials
Beach nourishment for the Noosaville foreshore project will require < 5000 tonnes per
year to complete the four approved areas. Approximately <2000 tonnes of sand, in
total, is required to be dredged from sites 1 and 2. There will be no waste released,
stored, transferred or disposed of into the environment. Sand materials will be
deposited on beach riverbed areas as per NRM Soil Management Guidelines. Due to
the lack of pyritic fines in the substrate of the selected dredge areas, no redeposition
or movement of any waste products will be performed (refer to 7.1 of this document).

2.2 Scale location plan
See location plans attached in Figure 1.

2.3 Dredge and borrow areas
The eight areas identified contain both the beach nourishment area and associated
sand resource areas. The purpose of dredging is only to replenish sand on river
beaches and protect Council infrastructure. No dredged sand will be removed off site.
There will be no contamination to stormwater drains or runoff from cleaning of
equipment, and no release of contaminant to any land areas. Dredge areas have been
selected adjacent to one another within the main tidal flow area of the river. Dredging
of the left side of the riverbank may cause currents to erode or deposit sediment on the
adjacent bank this is due to high dynamic characteristics with intense tidal factors
playing a commanding role on the river meandering process. Selection of banks
adjacent to one another is considered as effective way of confining effects that could
impact other areas of the river system (Hey, 1997).


River equilibrium is generally determined by the controlling factors that cause a
displacement of the equilibrium in a direction that will tend to absorb the effect of the
change. The controlling factors in this system are width, depth, velocity of the tidal
flow, slope, discharge, size of sediment, concentration of sediment and roughness of
the channel (Hey, 1997). None of these factors will be affected as a result through the
extraction of sediment at these sites. This area of the river has a steady state in which




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