Restoration of Scenic Drive at Bilambil Heights is one step closer with the awarding of a contract to design and construct repair works for the badly damaged road.
Council has awarded Australian Marine and Civil Pty Ltd the contract to design and construct Scenic Drive landslip and embankment restoration works.
Funding for the contract, worth more than $2.5 million, has been sourced through Disaster Recovery Funding Arrangements (DRFA) with approval from Transport for NSW.
The contractor will now start design works which will include planning construction to commence on site as soon as possible.
Acting Director of Engineering Tim Mackney said awarding of the contract was a key component in addressing the very complex job.
"We can now start on design work and once that is approved, gain environmental approvals, before the contractors engage specialist plant, equipment and subcontractors to carry out the construction works," Mr Mackney said.
"The proposed construction process for Scenic Drive will involve site establishment, excavation of slip areas, soil nailing, concrete shotcreting, foundation works, wall construction, backfill, drainage, road pavement, asphalting, line marking and safety barrier works.
"The contractor has provided an indicative timeframe, which aims at having works completed by the end of March 2023."
Meanwhile, geotechnical experts have recommended the partial closure of Beltana Drive at Bilambil due to safety concerns. They have advised further movement or collapse of the scarp is likely, particularly following wet weather.
To ensure the ongoing safety of road users, the road will be closed at the landslip site as soon as possible.
Further geotechnical investigation work is being organised to formulate the design of restoration works and construction at this site. This too is a complex site and, given the wide extent of damage throughout the Shire, it is anticipated the road will be closed for at least 12 months. Fortunately, Beltana Road is a loop road and access can be maintained for all residents.
Mr Mackney said progress was continuing on the geotechnical investigation into the major landslip at Tyalgum Road.
"The landslip is the largest, most complex and expensive road repair job facing Council following the flood," he said.
"The damage is affecting 110 metres in length of road surface as well as some 50m height of slope above the road on private land as well as steep, heavily vegetated slope below the road leading to the Oxley River.
"We have contracted geotechnical experts to assess the damage. As part of their investigations, engineers will be required to identify failure mechanisms, the depth of failure planes and to develop remedial options.
"Their final report is due to be delivered to Council by August after which we will prepare a tender and issue it to the market.
"Unfortunately due to the steep, heavily vegetated slope below the landslip, as well as the steep slope and likely failure plane on private property above the road, the site is not conducive to temporary access.
"We know this is not great news for the local community who will need to continue to use the Limpinwood Road diversion, but to build a safe temporary road would require the same amount of geotechnical investigation and design as the permanent solution – and so there are no simple fixes to resolving the situation more quickly."
On Limpinwood Road, further geotechnical tests will be carried out from 7 July to complete the testing delayed by wet weather a month ago. This is the earliest date geotechnical crews could return to carry out the work. Bore holes will be drilled near the existing landslip with samples than sent off for analysis. The result from these test will help to determine the next steps in the road restoration.
Council understands that works will cause disruption and inconvenience due to slightly longer travel times and asks for residents' patience as restoration works are carried out. Council is prioritising repair works and maintenance on alternative access routes.
