Download MEW E101 April 2013 (pdf, 280kb) - NSW Public Works

Part 1 - Installation
The entire underground reticulation system shall be inspected prior to cable installation.
At this time the drainage system will be checked using water inserted at various points
and the system must drain free of water within two (2) hours.
Notify the Superintendent of required inspections two (2) working days prior to the
inspection.
104.1.3 Backfilling and Reinstatement
Bed PVC conduits on 50 minimum of clean sand and cover by a further 50 of clean sand
before backfilling the trench.
After laying the conduits in unpaved areas, backfill the trench and consolidate to about
10 above the natural ground level. Remove all excess spoil from the site.
Existing grassed areas shall be backfilled and turf re-laid on prepared bed or otherwise
re-grassed to 10 above natural ground level.
In existing concrete or brick paved areas, backfill the trench with clean sand to the
underside of the reinstated pavement and consolidated by watering and mechanical
compaction. Reinstate surfaces to the original level. For concrete surfaces use
approved reinforced steel, keyed to the existing to prevent the reinstalled concrete from
subsiding and cracking.
In existing bitumen paved areas, camber the reinstated surfaces so that the edges are
flush and the centre is 10 above the existing pavement. The top 150 (minimum)
immediately below the bitumen, shall consist of finely crushed gravel mechanically
compacted into the trench. Prime the existing bitumen edges of the trench shall be
prime coated with bitumen prior to laying 75 minimum of hot "pre-mix" bitumen to the
finished cambered surface. If it can be shown that hot pre-mix is not available, cold premix
will be accepted.
104.2 Underground Cable Protection
To preclude damage, cables installed in pipes shall be drawn using rollers, drumjacks
and a cable stocking of the correct size.
A 150 wide orange marker tape bearing the words "WARNING - ELECTRIC CABLE
BURIED BELOW" or similar and manufactured in accordance with AS 1648, Part 1, shall
be laid in the trench 150 below ground level for the entire length of all underground cable
and conduit runs.
Marker tape is also to be provided over conduits and pipes installed underground for
future use.
104.3 Underground Cable Draw-In Pits
Provide draw-in pits for underground cables as indicated. Where the size of the pit is
indicated, the dimensions refer to inside dimensions. The pits walls and bottoms to be
minimum 100 reinforced concrete. The concrete shall contain an approved additive to
prevent ingress of water.
Alternatively proprietary type glass reinforced moulded cement pits or "Polycrete" with
minimum 10 thick walls and bottom may be used and installed in accordance with the
manufacturer's instructions on a minimum 100 thick gravel aggregate bed which shall
extend under the entire pit bottom. Encase the pit in a 100 thick reinforced concrete
surround with the top neatly finished.
Drain all pits. The minimum drainage requirement is a 300 x 100 deep rubble drain
graded away from the pit for a distance of 2000.
Pits greater than 400 wide shall be fitted with covers and frames of cast iron or
aluminium and concrete. The covers shall maintain a stabilising fit with the frame by a
taper contact on the sides. All vertical mating surfaces to be fitted to a maximum
clearance of 0.25 mm.
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MEW E101