Eurobodalla Integrated Water Cycle Management Strategy

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Eurobodalla Integrated Water Cycle Management Strategy
Treating effluent at a local facility would result in a number of options for the management
of reclaimed water. Appendix P provides a detailed description of the available
management options. Preliminary appraisal suggests river disposal, or agricultural reuse as
the most suitable options worthy of further evaluation.
Costs in Table 9-5 are based on centralised effluent drainage (CED) for transport, a local
package plant for treatment and river disposal.
Provision of a Full Reticulated Sewerage System
An alternative to providing any on-site treatment facilities is to transfer wastewater (i.e.
black and greywater) through a centralised sewer transport network to either a local
treatment facility as discussed for the previous opportunity or to the Batemans Bay STP. A
slight variation on this option would be to incorporate local greywater reuse and only
transfer blackwater to the Batemans Bay STP.
Unlike in the previous opportunity, the sewer transport pipes would need to be larger and
possibly installed at greater depths.
Appendix P provides a detailed description of the available transport and local treatment
options. The shortlisted reclaimed water management options are the same as those
discussed for the above opportunity.
Costs in Table 9-5 are based on a modified gravity transport system, a local package
extended aeration treatment plant and river disposal.
Provision of Full System with Greywater Reuse
On-site systems that achieve a suitable level of treatment for greywater would be
maintained, and blackwater only would be transported to the Batemans Bay STP using the
reticulation systems described above. The resulting greywater could then be utilised for a
variety of outdoor uses and for toilet flushing. Maintaining current aerated systems in
Nelligen for greywater reuse would reduce the volume of wastewater requiring treatment by
0.325 ML/a. If in addition, current septic tanks were converted to rainwater tanks for reuse
purposes an additional 3.6 ML/a could be saved. In addition to reducing the volume of
imported or reticulated water required for Nelligen, this would reduce the hydraulic load on
the Batemans Bay STP. With the implementation of appropriate monitoring systems, long
term environmental and water resource sustainability and public health protection could be
achieved.