ordinary meeting of council to be held on tuesday, 26 april 2005 at ...

Ordinary Meeting <strong>of</strong> Council - 26 April 2005 8 / 4
Item 8
DA0177/03
24 March 2005
incorporate <strong>be</strong>nching <strong>to</strong> improve hydraulics in the s<strong>to</strong>rmwater system that reduces the
occurrence <strong>of</strong> up welling.
ii.
iii.
Provision <strong>of</strong> overland flow route is designed <strong>to</strong> convey the flow (<strong>of</strong> 607 L/s) from a 5 year
ARI design s<strong>to</strong>rm event and is accordance with DCP47 requirements. The flow route at its
critical section operates as a weir that accommodates the full 5 year ARI design flow without
over<strong>to</strong>pping the driveway.
To ensure there is a low risk <strong>of</strong> flooding in<strong>to</strong> the garage due <strong>to</strong> the proximity <strong>of</strong> the relief
overflow route <strong>to</strong> the driveway <strong>of</strong>f Burgoyne Street, measures include:
• Replacement <strong>of</strong> 7metres <strong>of</strong> 150mm high kerb with a 4 metre shallow sloping vee
section gutter 75mm in height with transitions on both sides, such that excess gutter
flows are facilitated in<strong>to</strong> the overland overflow route. The sloped vee section is not
considered <strong>to</strong> interfere with parked cars.
• A transitioned flowpath route is proposed across the nature strip which is depressed
<strong>be</strong>low the driveway level by 90mm at the layback and 250mm at the boundary. Revised
drawings GD2.1, GD2.4 and GD2.7 Revision D were submitted <strong>to</strong> include amended
levels <strong>of</strong> the driveway layback.
• Barrier for the gutter flows likely <strong>to</strong> occur on both sides <strong>of</strong> the relief route by use <strong>of</strong> the
driveway layback and 150mm high kerb.
• Larger than standard trench grate (TD1) fronting the garage designed 400mm wide by
300mm deep with a 225 diameter outlet pipe conveyed <strong>to</strong> the downstream pit.
iv.
Drainage Works proposed in Burgoyne Street comprise two modified and two new road pits
with 2.5 metres <strong>of</strong> 375mm pipeline. The proposed road pits and grates were assessed and
provide equivalent inlet capacity as existing with account made for the reduced ponding
depth.
v. Structural capacity <strong>of</strong> the 600mm pipe <strong>to</strong> withstand construction loads. Class 2 pipes are
typically at risk during construction when loaded by heavy equipment. Based on the long
section, adequate cover (<strong>of</strong> 0.9 - 2.4 metres) is provided with the nature strip but not
considered adequate within the property with the depth ranging 0.5 – 0.9 metres.
The abandoned 450mm pipeline within No.15 is <strong>to</strong> <strong>be</strong> sand filled and is considered satisfac<strong>to</strong>ry.
Integrity <strong>of</strong> the pipeline should <strong>be</strong> protected by restricting the area over the pipeline from heavy
construction machinery during construction <strong>of</strong> the dual occupancy. Temporary fencing on the
easement in this instance would <strong>be</strong> appropriate as a measure that Council can condition, and
following completion <strong>of</strong> the dwelling, it would <strong>be</strong> prudent <strong>to</strong> undertake an inspection <strong>of</strong> the pipeline
by CCTV with a copy supplied <strong>to</strong> <strong>council</strong> for verification prior <strong>to</strong> issue <strong>of</strong> occupation certificate.
Road Opening Application
Drawing GD 2.6 submitted shows and descri<strong>be</strong>s the Traffic Management Plan as well as the
sediment and erosion control measures per condition 3 <strong>of</strong> the pre-commencement conditions.
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