FRRB SLP 0034 - Crofton Rd Slip

The works are located approximately 4.8km towards the end of Crofton Road, Nimbin and is adjacent to Goolmangar Creek. Emergency work was completed over 3 years ago as a temporary rock embankment and gravel road repair.

There are two damages to be repaired as part of this scope of works:

1) DM01429 - A creek embankment landslide caused significant road and pipe culvert damage and

2) DM01431 - 400m of Crofton Road pavement that has failed due to flooding.

1. Embankment Works

A summary of the works are:

• Clear, grub and mulch site area including embankment and table drains.

• All works associated with design drawings for the reconstruction of the road including pavement, foundation and embankment rock RIPRAP protection.

• Replace existing RCP 600mm Dia (including upstream pit) with new twin DN450 Poly SN8 pipes and headwalls as per drawings.

• A new W beam guard rail (Ramshield) and edgeline marking.

• Sub-surface drainage is required.

• Shaping of table drains and scour protection.

• Modified pavement detail to the Base layer of DGB20 (see Pavement Works)

Pavement Works

There is 400m section of sealed pavement reconstruction from Chainage 4.8km north and including a turnaround point with a nominal 4.5m width. Within this is the designed ‘Sealed Pavement’ works at the embankment site (approx. 35m). Note the designed detail for the Base (150mm DGB20) is Provisional. It is substituted to match this 400m whole of pavement treatment. The pavement stabilisation works will be 2% 70/30 lime/cement stabilized adding 100mm DGB20 and stabilise 200mm. The Pavement Seal will be the same as the design drawings as 14/10 Double sealed wearing course with 7mm Primer Seal.

See Scope of Works document for further details.