Eurobodalla Integrated Water Cycle Management Strategy

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Eurobodalla Integrated Water Cycle Management Strategy
Centralised Management of Effluent from On-site Facilities
As an alternative to providing a full reticulated sewage system, the effluent from existing onsite
systems (e.g. septic tanks) could be collected and transported to a central treatment
facility. The pipes used may be smaller and could be laid in ground flatter and at a shallow
depth than conventional gravity sewerage, as the pipes carry only entrained solids thus
requiring minimal self cleaning velocity. The effluent collected form Moruya would be
transported to Moruya STP for treatment.
Provision of Full Reticulated Sewerage System
An alternative to providing any on-site treatment facilities is to transfer both the solids and
liquid through a common sewer transport network to Moruya STP. Unlike in the previous
opportunities the sewer transport pipes would need to be larger and possibly installed at a
greater depth. Installing sewerage reticulation to transfer to Moruya STP would require 9.5
km of pipeline along existing roads.
Provision of Full Reticulated Sewerage System with Grey Water Reuse
On-site systems that achieve a suitable level of greywater treatment would be maintained,
and blackwater only would be either transported to the Moruya STP using the reticulation
systems described above, or would undergo local treatment and management. The
resulting greywater could then be utilised for a variety of outdoor uses and for toilet flushing.
Maintaining current aerated systems in Congo for greywater reuse would reduce the
volume of wastewater requiring treatment by 0.86 ML/a. If in addition, current septic tanks
were converted to rainwater tanks for reuse purposes an additional 2.8 ML/a could be
saved. This in addition to reducing the volume of imported of reticulated water required for
Moruya, would reduce the hydraulic load on the Moruya STP. With the implementation of
appropriate monitoring systems, long term environmental and water resource sustainability
and public health protection could be achieved.