Woodhill Mountain Road - Woodhill - Landslip & Pavement Repair

12/3/2024 - Announcement: Good news - contraflow traffic conditions are now in place for the remaining works. Final pavement and asphalt work, line marking and removal of equipment and personnel from the construction site is planned to be completed by days end, Sunday 17 March 2024, weather permitting.

27/2/2024 - Announcement: Landslip repair works are progressing well. See Related Documents for the updated 3-week Lookahead Program 27 February 2024. 

Contractor Symal released revised construction program, the updated three-week Lookahead Program, refer to Related Information. Repair works and road closures are detailed under 'About the works'. 

20/2/2024 - Announcement: Due to necessity, the extent of mesh and shotcrete works has been extended by the engineer. The impact to the works program is one week of additional closures. See details below: About the works

2/1/7/2024 to 23/2/2024 – The updated three-week Lookahead program was released each week by contractor, Symal, and published on this page weekly under ‘Related Information’. Repair works and road closures were also detailed weekly for all sites under ‘About the works’. 

Repair works in progress

Below: Site 1 near rural address 552 landslip repair works underway and nightworks 16 November. 

Below: Site inspection of repair works 8 November with Symal and Council senior project managers. 

Below: Night works under construction 9 November. 

Below: Initial clearing and preparation for landslip repair works. 

1/7/2023 to 22/12/2023 – The updated three-week Lookahead program was released each week by contractor, Symal, and published on this page by council weekly, under ‘Related Information’. Repair works progress and road closures were also detailed weekly for all sites under ‘About the works’. 

30/6/2023 - Updated two-week look-ahead program released by Symal. Refer Related Information.

27/6/2023 - Updated two-week look-ahead program released by Symal. Refer Related Information.

21/06/2023 - Contractor Symal releases revised construction program. See 'Construction Program - Remediation - Multiple slips - Shoalhaven' under Related Information.

15/06/2023 - Local sub-contractor A&D Tree Services commences tree trimming works in preparation for Symal contractor works.

05/06/2023 - Updated two-week look-ahead program released by Symal. Refer Related Information.

16/05/2023 - Updated two-week look-ahead program released by Symal. Refer Related Information.

08/05/2023 - Mobilisation of construction equipment to commence soon. Updated two-week Lookahead program released by Symal. Refer Related Information

30/03/2023 - Landslip design plan for Woodhill Mountain Road is attached. Located under - Related Information

30/03/2023 - Landslip repair drop-in sessions: THURS 30 March 4 – 5pm THURS 13 April 4 – 5pm. Drop by the Kangaroo Valley Hall (177 Moss Vale Rd) where Symal and Council will answer your questions about upcoming roadworks.

17/03/2023 - Kangaroo Valley Information Session on Friday 17 March, 7pm - 8pm (followed by BBQ) at KV Community Hall. Meet contractor Symal and get briefing on the start of landslip works.

04/03/2023 - The latest construction program proposed by contractor Symal for the 38 the Major Landslip repair work has been released. The construction program lists the planned start and finish date for each of the 38 land slips. A summary of the construction program is available on the  Major Landslip Package Planned Program of Work. A copy of the construction program is also available on the right-hand side of the Master Project Page in the related documents section.

15/2/2023 - Contract awarded - Council has resolved to proceed with the appointment of infrastructure and construction group Symal to repair the 38 major landslips. Council has provided Symal a schedule of works which prioritises the most urgent landslips with the first round of works to begin in late March 2023. To view the list of major landslips and the assigned construction priorities, refer to the Major landslip package priorities on the Master Project Page

• 22/12/2022 - Four tenders for the repair of 38 landslips were received. A comprehensive evaluation process has been completed and a recommendation has been forwarded to Public Work Advisory (PWA) for endorsement. It is anticipated that PWA will evaluate the tender acceptance report and respond to Council mid-January. Further information can be found on the Master Project Page

  Survey

  Council has now completed the geotechnical assessment and survey which confirmed concerns about the stability of the zone around the initial slip.
  
  • The area is considered to be dangerous to enter as many large rocks and trees still on the slope have the potential to fall onto the roadway. Safely removing the material and address the larger stability issue will be a challenge.                                                   
    Clean up and recovery

  • Works will begin on 21 July and are expected to take around two weeks to complete, weather permitting. Works include:

  • Shifting debris to one side of the roadway to allow traffic to one lane and limited to local traffic (larger rocks will remain as a barrier because they are currently contributing to the stability on the landslide).

  • Opening the second lane by removing both the unstable material on the up-slope side and the remainder of the material at the bottom of the slope. During these works the road will need to be closed intermittently for the safety of motorists. This process is expected to take approximately two months.

         Investigation, design and remediation

  • Options being considered for the long-term stability of the slope and safety of motorists include:

  • An anchored rock fall barrier
  • A anchored rock fall barrier with catch fence
  • Slope retention – mesh and anchor bolts
  • Gravity retaining structure

   The appropriate application will be decided after the clean up and recovery phase.

  

   

  22/12/2022 - Four tenders for the repair of 38 landslips were received. A comprehensive evaluation process has been completed and a recommendation has been forwarded to Public Work Advisory (PWA) for endorsement. It is anticipated that PWA will evaluate the tender acceptance report and respond to Council mid-January. Further information can be found on the Master Project Page Severe weather events reconstruction work - 2022 | Shoalhaven City Council (nsw.gov.au)  

• 03/11/2022 - Following months of geotechnical investigations, design work and tender preparation, Council is now seeking contractors to bid on the 38 landslips deemed a priority. Submissions closed 6 December 2022.Shoalhaven Area – Remediation of Multiple Slips – RFT – 10053781.

• 02/11/2022 - Pothole repair was completed along Woodhill Mountain Road in the beginning of November 2022.  It is regularly being monitored and repaired where and when necessary.

• 01/10/2022 - Critical repair work on Woodhill Mountain Road scheduled for Tuesday 1st November was cancelled due to the rain conditions yesterday. Repair will continue Wed 2 November to Thursday 3rd November. The road will be closed on both sides of the landslip from 7 am until 4 pm. 03/11/2022 - Works are now completed. 

• 30/10/2022 - Critical repair work on Woodhill Mountain Road runs for three days, Mon 31 October - Wed 2 November. The road will be closed on both sides of the landslip from 7 am until 4 pm. Due to HSC exams, students needing to catch the school bus during this time will be escorted safely through the site. Please meet at the top end of the slip at 7.25 am sharp (bus departs from down-side of slip at 7.35 am).

• 20/10/2022 - Critical repairs and excavation works need to be carried out on Woodhill Mountain Road next week. While night works would have been preferable, unfortunately this is not possible due to asphalt delivery. The road needs to be closed (on both sides of the landslip) from 7 am until 4 pm on these three days - Monday 24, Tuesday 25 and Wednesday 26 October.

• 04/10/2022 - With rainfall forecast for the Shoalhaven, Council reminds residents that it may become necessary to close access roads previously impacted by land slips. The trigger is 40mm of rain within any 24-hour period. Council will provide as much warning as possible should this occurs. Maintaining road safety and access across the city remains Council's highest priority.

• 22/09/2022 - Following record rain events, Council has recorded 98 landslides as a high priority, with a focus on 35 sites that are deemed most urgent. We've now finished geotechnical investigations at these 35 sites, leading the way for designs to be completed in the coming weeks. The designs form part of a works package that will go out to tender in October.

• 09/09/2022 - Geotechnical engineers will be conducting a site investigation on Woodhill Mountain Road from Monday 12th September 2022 for approximately 5 days.The road will be open, under traffic control.

• 7/09/2022 - Woodhill Mountain Road is open 24 hours / 7 days

•  No weight limits

  Restrictions

  • One lane only

  • Stop / slow signs

  • Reduced speed of 40 km/h - extreme caution should be taken when passing.

• 04/09/2022 - Geotechnical engineers will be conducting a site investigation on Woodhill Mountain Road, Monday 5th September 2022. The road will be open, under traffic control.

• 26/08/2022 - Conditions have changed today from 6am

• Woodhill Mountain Road is now open 24 hours / 7 days

  • No weight limits

  This follows a risk assessment at the Woodhill Mountain Road landslip, undertaken on Wednesday, that confirmed movement on the upper slope was decreasing. 

  Restrictions

  • One lane only

  • Stop / slow signs

  • Reduced speed of 40 km/h - extreme caution should be taken when passing

• 26/08/2022 - The latest risk assessment for the Woodhill Mountain Road landslip, undertaken on 24 August, has shown that movement on the upper slope has decreased and therefore the risk has reduced. Accordingly, as of 6am Friday 26 August, Woodhill Mountain Road will be open 24/7 under traffic control.

• 25/08/2022 - Council undertakes regular reviews and monitoring of all 98 landslips for changes to the risk (combination of likelihood & consequence). The latest risk assessment for the Woodhill Mountain Road landslip, undertaken on 24 August, has shown that movement on the upper slope has decreased and therefore the risk has reduced. Accordingly, as of 6am Friday 26 August, Woodhill Mountain Road will be open 24/7 under traffic control. Council would like to thank the community for their patience and acknowledges the frustration, however safety has always been the key priority for Council. The community is reminded that the road could be closed down at short notice, due to the weather increasing the risk.

• 22/8/2022 - Woodhill Mountain Road is open, 6 am through 8 pm, daily with the current restrictions -- One lane only - Stop / slow signs - Reduced speed of 40 km/h - extreme caution should be taken when passing - No weight limit Should any further signs of instability be observed, additional geotechnical advice will be required.

• 10/08/2022 Yesterday evening, some small movements and rocks were observed coming down at the slip and the instruction was to close the road until a proper inspection could be made today, 10 August. 

• 06/08/2022 Recent fine weather has ensured the road remains open, between 6 am and 8 pm, daily. As a reminder, the other restrictions are:

• One lane only
• Stop / slow signs
• Reduced speed of 40 km/h - extreme caution should be taken when passing
• No weight limits

5 August 2022

1. Works have been completed with regard to the first stage of the removal of debris and removal of loose rocks that have potential to fall and impact upon the road.
2. Concrete jersey barriers with rockfall protection fencing have been installed at the inside of the road centreline to act as a barrier for potential ongoing rock falls; however, residual risks still remain for larger rock falls, debris flows and trees toppling.
3. On this basis, there are still inherent risks to road users, therefore extreme caution should be taken when passing the affected area.
4. Traffic will be restricted to one lane under traffic control, with a speed restriction of 40 km/h.
5. Restricted one lane access will be provided from 6am to 8pm.
6. At short notice, the road could be restricted to local residents only where high wind and/or rain is forecast or occurs, that could activate further failure and hazards to road users. Trigger characteristics include: (i) Heavy rain forecast; (ii) Nowra station record ≥ 30mm / 24hr; (iii) Nowra station record ≥ 40mm / 72 hr; (iv) More rain predicted > 30mm / 24 hr; or (v) Wind Gusts > 30 knots.
7. At short notice, the road will be closed where high wind and/or rain is forecast or occurs, that could activate further failure and hazards to road users. Trigger characteristics include: (i) Severe rain forecast; (ii) Nowra station record ≥ 40mm / 24hr; (iii) Nowra station record ≥ 60mm / 72 hr; (iv) More rain predicted > 40mm / 24 hr; or (v) Wind Gusts > 45 knots.
8. Development of the long-term remedial solution is underway, with progress of such being provided here as the solution develops
   
   

• 02/08/2022 Council inspected the Woodhill Mountain Road site and confirmed they would proceed with the plan to have one lane opened to traffic through the landslip site as scheduled by 8 August 2022, providing there are no further negative changes to the slip area.

     The inspection facilitated an impromptu meeting with about a dozen residents impacted by the road closure, at which Council explained the current line of thinking in relation to the works and reopening:

1. Works will continue to remove loose rock
2. Concrete jersey barriers will be placed at the foot of the cutting to guard against loose rock
3. Restricted one lane access will be provided from 8am to 6pm
4. At short notice, the site may be shut down should the forecast winds and/or rain cause further damage or dislodge more material
5. Communication to all residents of Woodhill Mountain Road (number 450 and greater), Brogers Creek Road and Wattamolla Road will now be sent updates via email daily at 2pm
6. This information will be available on this page at a later stage, most likely this will be the next day
7. Work towards developing longer-term solutions for the road will continue. This information will be shared within the 2pm daily update

Subscribe to this page and be notified of daily updates. 

Maintaining road safety and access across the network is Council's highest priority. The extent of the damage across the city means that temporary works and rework is undertaken as soon as possible.  The longer term works are scheduled at later dates as investigations, plans and risk assessments develop.

• 26/07/2022 Clean up and recovery works have commenced as planned on 21st July 2022. These works will be undertaken in four stages in order to safely progress towards the opening of one lane of traffic. These works are staged as follows:

• 06/08/2022 - It should be noted that weather warnings have been provided by the Bureau of Meteorology indicating strong winds over the weekend. The site will be monitored constantly and Council will assess the safety of the operations regularly. It may be possible that the road could be closed at short notice as a result of more material being dislodged.

• 04/08/2022  - An on-site inspection Wednesday 2nd August confirmed progress towards Council’s plan to have one lane opened to traffic through the land slip site, on the 8th August 2022. The inspection turned an impromptu meeting with about a dozen residents affected by the road closure. 

• 21/07/2022 - Following a landslide on Woodhill Mountain Road on 14 July, a geotechnical assessment has now been carried out with a three-stage approach to re-open the road.  One lane could be open by 8 August 2022

• 14/07/2022 - Woodhill Mountain Road is currently closed due to a landslide on Thursday 14 July. Very large rocks, trees and soil are blocking the road, making it impassable to all traffic. Council is calling on specialist equipment to clear the road. The site is currently being inspected by geotechnical engineers at which stage we'll be able to determine how long the road will need to be closed.

• 14/07/2022 - Woodhill Mountain Road is currently closed due to a landslide that occurred this morning. The site is currently being investigated by our team.

• 08/07/2022 - Woodhill Mountain Road closed due to worsening weather conditions. Traffic control is in place. Emergency vehicles and residents only.

• 30/06/2022 - Load limit remains in place and continues with one lane. Motorists are asked to drive to the conditions.

• 23/06/2022 - Drill bore logs are now included in the Geotechnical report enabling transition and handover for design to be undertaken.
  
  

• 16/06/2022 - Geotechnical drilling was conducted this week. This will enable design works to begin once results are received.
  
  
• 09/06/2022 - Night works have been completed on the major pavement repairs to Woodhill Mountain Road. Geotechnical drilling will be undertaken week starting 14th June 2022 under local traffic controls. This is the final step before design works for landslips can be undertaken. One lane continues to be open with traffic lights.

• 04/06/2022 - Road repair works commenced last night. Night works will continue on Sunday and Monday night to minimise disruption to users of Woodhill Mountain Road.

• 02/06/2022 - Investigations continue into Woodhill Mountain Rd landslip. Pavement repairs are scheduled to commence on the 3 June 2022 (conditions permitting). All works are planned to be undertaken over three consecutive night shifts with construction site traffic control in place. 

• 26/05/2022 - Pavement repair works were scheduled - due to wet weather work has been delayed. As soon as conditions permit council will conduct scheduled work. Please observe signage and stay within speed limits.  

• 30/04/2022 - Geotechnical inspections and testing underway.

• 18/04/2022 - Initial investigation completed.
• March 2022 the landslip location along Woodhill Mountain Road, about 1.0km south of Mountain Road and Wattamolla Road intersection (Figure 1). The site is comprised of a cut and fill formation constructed on a south facing hill and is located above extremely steep slopes. Settlement along the crest and north bound lane is observed and washout and slumping are observed downslope of the crest. Erosion is also observable on gullies east of the barricaded area. Significant pavement damage has also been identified in various locations requiring rectification (Figure 2).

• Figure 1: Woodhill Mountain Road landslip               Figure 2: Pavement damage