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at Potsdam. This non-potable irrigation water, referred
to as Potsdam, is recycled water that is freely available
within the Century City precinct and commonly used for
irrigation purposes.
Buffer tanks are placed between each of the filtration
processes, with the interconnecting pumps managed by
a control system. The entirety of the plant is connected
to a generator standby power, assuring the system is
available for use in the event of a power failure.
In this manner, the Estuaries Plaza building uses
approximately zero potable water from the municipal supply
under normal design building demand, and the overall
discharge to the municipal sewer is drastically reduced.
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RO plant pre-filtration and dosing pumps.
Booster pump set.
Cartridge filters.
Bio-digester tanks in the basement.
Water purification system components
a) Black- and grey water treatment bio-digesters
Gravity fed by the building’s black- and grey water
drainage system, bio-digesters anaerobically digest the
drainage water, producing methane gas and treated
water. The methane gas is directed to the basement
security room for cooking use. Treated water is then
gravity fed to a storage tank before further treatment.
The bio-digesters were recently removed from the system
though, even though the system operated successfully.
This was mainly because the outflow from the bio-
digesters was placing too much of a strain on the RO
membranes, and the cost of cleaning and replacing them
could not be justified. The system still does not use any
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May 2017 Volume 23 I Number 3