wastewater disposal and water supply preliminary report woodlane

with a view to decommission the plant. Council believes that the existing
combined 44kL storage capacity at the plant will be good for at least 24 hours
in the event that SA Water supply fails. Council views that with less than $2,000
implementation cost there is a potential saving of $20,000 p.a. with a once off
income from the sale of the treatment plant, and in turn potentially fund the
purchase and installation of water meters to ensure cost recovery under a user
pays system.
W&G would suggest a modified version of Option 1 be progressed with SA
Water as the preferred option. We would suggest that after the water meter
that a pipeline be extended to the existing water treatment plant and the two
existing tanks used for buffer storage. These two tanks have a combined
capacity of 44KL, SA Water have suggested a 100KL storage. Given that 44KL
is approximately equivalent to 1 days peak use the existing tanks may be
adequate. Council could initially implement this solution at a very minimal
construction cost and with very little disturbance to the existing infrastructure.
Should Council find that this storage is not adequate then an additional 50KL
tank could be added at a later date. Council may choose to add this additional
storage to provide a greater buffer storage at the site that can supply the area if
the supply through the SA Water main is interrupted for an extended period of
time. This 50KL storage could be provided with an off the shelf poly tank,
provided it was fenced off, This would provide a cheap storage solution. If
vandalism is of concern then a concrete tank could be used.
This option has a low capital cost, removes the need to pump from the Murray
River, reduces Council’s risk exposure, reduces Council’s maintenance and
monitoring requirements and would result in minimal disruption to local
residents.
Finally the advantage of being able to embark on its provision almost
straightaway makes Option 1 a more sound option for Council, as opposed to
having to be tied down with the progress of the new proposed pipeline
construction.
SA Water has expressed to W&G that they shall provide a budgetary costing
for the supply and installation of both the 20m and 26.5m pressure setting
PSV’s and the “roadside” water meters. A comparison of implementation cost
between all three options can thereafter be undertaken for further assessment.
Woodlane Wastewater Disposal and Water Supply Preliminary Report
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