Update: Project Rawene

Auckland Council is leading engineering works at the Rawene Road car park in Birkenhead to ensure the safety of the surrounding area and to progress a long-term solution for the two slips that occurred in late 2017.

Regular updates on work in progress will be available on OurAuckland. To subscribe to receive these updates by email or to ask questions about the Rawene project contact rawene@aucklandcouncil.govt.nz

A record of previous updates is available here and a number of our most frequently asked questions about the project can be read here - Birkenhead slip - What you need to know.

Project information is also available on the Auckland Council website.

Rawene Response Update – 9 May 2018

Public meeting

Thank you to those that attended last Tuesday night’s Public Meeting. Approximately 50 members of the local community attended the meeting. In addition to the project team, members of the Kaipātiki Local Board also attended and assisted with queries. Thank you to Arlene and Alyson, of Rawene Centre, for their assistance and organisation of the venue.

The slides from the meeting are available here for the next 30 days. There were two presentations at the meeting. Ross Roberts (Geotechnical and Geological Practice Lead) summarised the land slip work to date and the next phase of work. Lisa Spasic (Senior Project Lead for the Birkenhead Mainstreet Upgrade) outlined the project and construction staging, including a communications plan, for the town upgrade. Both Lisa and Ross explained how the projects would overlap and be coordinated together. A summary of their presentations is included below.

The meeting concluded with a question and answer session. The key questions have been documented below. Please note that we have tried to faithfully transcribe those questions and answers that would be of use to everyone

Rawene Land Slip Stabilisation (summary from Public Meeting)

Ross described the history of the slip occurrence and provided a brief outline of the work to date on the site for all present. He confirmed that the emergency works (sheet pile installation) undertaken on site during and since the Christmas break have slowed the progression of the slip, resulting in a significant slowing of change to the ground since the works were completed.

The most recent work on site was the installation of a larger diameter temporary storm water pipe. This pipe is still temporary, but resilient enough to last the duration of the construction of the proposed stabilisation works. This has enabled the generator and pumps to be removed from the carpark.

Work is now about to start on Phase 1, which involves making the upper slope safe to work on and tidying up the previous emergency works at the crest. Mobilisation of equipment on site will begin in the week of Monday 7th May 2018. The Phase 1 work will include cutting of the sheet piles and the building of a concrete capping beam to tie the sheet piles together. Following this, trimming of loose material in front of the sheet piles, and on the sides of the top of the gully, will be undertaken to stop further regression. A new all weather working platform can then be created.

The work programme will require the closure of much of the Rawene Road public carpark and the private access lane behind the Mokoia Road shops at the top of the land slip at various times. Some public car park spaces will be available from time to time – this will vary during the works. Some of the carpark will also be used as a ‘lay down’ area for the Birkenhead Mainstreet Upgrade (‘the upgrade project’) to avoid taking up valuable parking spaces on the main roads. As Phase 1 progresses we intend to progressively re-open the private parking behind the Mokoia Road shops as soon as it is safe to do so, with access from the west. It is anticipated that the western end of the private lane will be opened first, as the eastern end of the site will provide access to the works in the slip and gully for the duration of the stabilisation.

Ross described the various design options for Phase 2 stabilisation of the site. Ross also commented on the outcomes from the public feedback following the previous public meeting about the design options. Generally, the feedback suggested:

There was a mixed reaction to the future use of the crest;
Many respondents agreed that future use of the site should be kept flexible to allow development, if suitable;
There was huge support for restoring the gully to bush, with linkages and access where possible; and
The public has strong concerns about parking in the area.

Ross highlighted that the stabilisation project scope is to restore land stability, and any further improvements to the site would need to follow on as subsequent projects with their own funding.

After a multi-criteria analysis which took into consideration the effects, stakeholders, safety, ease of construction, flexibility and costs, a modified option 4 was identified as the preferred option for Phase 2. This option comprises rebuilding the slope with natural materials from the bottom up, secured by a buried row of piles at the toe. The future design of the public carpark, following stabilisation, and subject to funding, will provide additional spaces, whilst being slightly lower down the slope. This design will be quicker and less expensive to build and means that possible future development of the site is not compromised. The design will also allow easier access down the slope as it will fit the natural topography of the ground best.

Phase 3 work in the gully will comprise the restoration of the gully floor, including the area further south into private land. This work is more safely approached in the summer months which will fit nicely into the timetable currently proposed. A lot of this work is on private land and requires more direct consultation with landowners. There are several affected properties and the process can be undertaken while Phase 1 and 2 are being constructed on site.

Birkenhead Mainstreet Upgrade Project (summary from Public Meeting)

Lisa introduced Duncan Millar, Auckland Transport’s (AT) Project Manager for the upgrade project. She explained that AT will manage the delivery of the project on site and are managing the build contract and that Auckland Council are both leading the project and funding the project via the Kaipātiki Local Board. Tenders from contractors to undertake the upgrade project have been received and reviewed following an open tender process. A final contract is yet to be awarded – but is imminent.

An independent Quantity Surveyor’s report predicted the cost of the project based on the Detailed Design drawing package, but the tender prices that came in were higher. The project team then consulted with the Kaipātiki Local Board to identify which elements of the design to build and which to leave for a later project when further funding would allow. The local board had the community’s interests in mind during this process and decided to upgrade all three sides of the roundabout at this time. Some other design elements have now been removed from the current upgrade project to ensure the project could be delivered on budget.

The upgrade project will take approximately six months to complete, although this includes contingency time (to allow for wet weather conditions) and Lisa is optimistic that it will be completed earlier. There is a construction staging plan which identifies how the works are delivered through the town centre and has been devised in collaboration with the Rawene Slip team to ensure that the two projects are well coordinated.

Construction is due to begin in late May 2018. There will be lane closures for road traffic requiring traffic diversions on and off throughout the works, but pedestrian access will be maintained to all shops and businesses throughout construction. A dedicated Communication Liaison Manager will be on site and available to meet with business owners during the project to ensure everyone is fully updated on progress.

Activities on site

Phase 1 stabilisation works are about to begin on site. CLL will be mobilising to the site this week. Initial construction works will include trimming of the sheet piles to ground level followed by excavation for a concrete capping beam. Detailed updates will be available as work commences.

Frequently asked questions

Questions and answers from the public meeting are available here, along with previous questions. We will continue to provide Q and A’s when we have information to share.

Parking Concerns

Recommendation to anyone that sees vehicles parked in a manner or place they consider dangerous or illegal in the Rawene Road/landslip vicinity:

If the vehicle is still there:

The fastest way for Auckland Transport to respond to illegal parking is to call them on 09 355 3553. A request for service record will then be created and a Parking Officer will be dispatched to investigate. We do appreciate this is not always possible or convenient however any assistance you can give us to address the parking issues in the vicinity of the land slip is appreciated

If the vehicle has gone:

If it’s too late for a quick response (perhaps they’ve already left) but you have images then please report them using the Auckland Transport ‘report a problem’ web page as this way your complaint will be formally recorded in Auckland Transports’ systems and can be tracked. This will help Auckland Transport customise their parking compliance approach to improve its service delivery. You can find the site here.

If you take any photos of vehicles in the Rawene Road/landslip vicinity you believe are illegally or dangerously parked, please also send a copy of the photo (if the registration is legible) to Rawene@aucklandcouncil.govt.nz and we’ll make sure they’re not working for us (and if they are, will take appropriate action).

Rawene Response Update – 17 April 2018

Stormwater pipeline

Healthy Waters have begun work to connect the existing drainage from the carpark to a temporary pipeline through the gully. So far this work has involved drilling the line with directional drilling equipment and pulling a pipe back through from the Rawene car park.

This is due to finish this week, which will allow the pumping equipment and generator to be removed from the Rawene car park.

Phase 1 works

Work at the top of the headscarp is programmed to begin on Monday 23 April.

Initial construction works will include trimming of the sheet piles to ground level, followed by excavation for the concrete capping beam. Weather permitting, this work should take 8-10 weeks. Work will begin at the eastern end of the site, beside the public car park, and work towards the western end of the site.

Impact of works

Workers and equipment will initially be positioned at the top of the landslip on private property to the rear of the Mokoia Road shops and the service lane. People can expect to notice noise and vibrations but these will not be as intense as when the sheet piles were first dug into the ground.

We expect that a lot of the effects of the work from the proposed remedial works will be of a very different nature to the sheet piling. The noise will be a more constant “background” source compared to the intermittent nature of sheet piling, and the noise and vibration levels will be much lower than those experienced during sheet piling.

Hours of work

Construction will only be undertaken during the hours 8am - 6pm Monday to Saturday and a construction site manager will be present on site at all times.

Phase 1 works are expected to be completed in 8-10 weeks (weather permitting) after which Phase 2 works will start. These will initially comprise the installation of new piles at the bottom of the landslide and filling will then begin of the main landslide body to create a stable.

Public Meeting

This will be held held on Tuesday 1 May 2018 at 6pm. The project team will give an update on Phase 1 works to date and discuss the next steps for the project for the next few months, and take questions from the community.

Outline of topics for discussion:

Update on Phase 1 works to date
What next? We will discuss the next stages of design, Phase 2, the construction programme, and what to expect.
Parking: issues and feedback.

Where: The Auditorium, Rawene Centre, 33 Rawene Rd, Birkenhead. Please note there will be other activities on at the centre so car parking cannot be provided on site.

On arrival, please sign in at the table in the reception area.

Rawene Response Update – 5 April 2018

Healthy Waters will begin work to connect the existing drainage from the carpark to a pipeline through the gully next week. This project is to provide a temporary stormwater pipeline to eliminate the need for the generator and pumps currently being used.

The pipe will be installed by winching the 350 OD diameter PE pipe through a track in the bush area. The work will take approximately 10 days to complete.

Public Carpark – Monday 8 April

Some of the public carpark will need to be closed temporarily to allow the equipment required to undertake the work to manoeuvre safely. This area is likely to be at the western end of the car park near the bottom of the ramp.

Private Access Lane and Parking - Monday 8 April

The lane will need to be closed while this work is undertaken. At this stage, it is likely that the area will be closed during the delivery of equipment and during the bulk of the work which is expected to take ten days. Can we please ask you to not park in the private parks from Sunday evening onwards, otherwise your vehicles may not be accessible for a week or more.

Next phase of work update

Following the construction of the new stormwater pipe, the generator and pumps will be removed from site.

Work on Stage 1 at the top of the headscarp is programmed to begin after Healthy Waters have completed their work. Timing will be confirmed via updates. Stage 1 work includes the capping of the sheet piles, possible ground anchor installation (if required) and construction of a retaining wall.

Next public meeting

We are proposing to hold another public meeting to keep you informed of progress. We have tentatively selected the evening of Tuesday 1 May as a suitable date. Please let us know if there are any reasons this date should be avoided.

If you have any questions or feedback please email rawene@aucklandcouncil.govt.nz and we will endeavour to answer as quickly and comprehensively as possible. This email address can be used to contact the project team, and is regularly monitored. You can also call the Auckland Council Contact Centre on 09 301 0101.

Rawene Response Update – 23 March 2018

On Saturday 24 March the neighbouring construction site has requested use of the carpark. They have a concrete pour booked and will use this area for the pump. In particular, they will cone off a couple of parking bays and control the delivery of trucks into and out of the car park from 7.00am and start to pour from 7.30am. They should be finished with the concrete around midday and are responsible for cleaning up the area afterwards.

Private Access Lane and Parking

The lane is currently open, but once the next phase of work starts it will need to be closed again for a period of about 4-6 weeks.

Release of Factual Data

The ground investigations at the crest of the slip are now largely complete, and we have just received the final factual report from our consultants. We are keen to share as much information as possible, so these reports have been put online. We will continue to share any factual reports that are not commercially sensitive as soon as we receive the final reviewed versions. The link below opens a page with two documents.

The first report, prepared by Opus International Consulting Ltd, is a Geotechnical Factual Report commissioned by Auckland Transport to undertake a geotechnical investigation of the landslide at the Rawene Road Carpark, Birkenhead in 2017. The investigation aims to provide input for the design of remediation measures. The second report, prepared by Tonkin & Taylor Ltd, is an investigation to assess the depth of fill materials on the ground above the landslip in proximity to the headscarp.

Both reports, in their entirety, can found using this link which will expire in 30 days: https://1drv.ms/f/s!Agz1AhnnYezjjbwdeM83D9nYYIRFQg

Update on next phase of work

The resource consent for the design for the next stage is now ready to be lodged with the council along with the written approvals from landowners and occupiers that may be potentially affected. The preparation of this phase began with the public meeting in February and consultation about future uses for the site. Those aspirations were considered during the design of options.

Following selection of the best option that ensured future development would not be impeded, that option then had to undergo detailed design, budgeting, and now consenting. Council is also required to go through a tendering process for all of this work.

The design is also going through a ‘peer review’ process to ensure it is not just the best option, but also the most safe and cost effective way to achieve the desired outcome.

As well as all of this ‘behind the scenes’ work, a number of safety and access issues are constantly being monitored on site, as well as parking, stormwater, waste water, more borehole investigative work and run-off at the base of the gully.

The next phase of physical work comprises cutting of the sheet piles (currently sticking up out of the ground) so that they are level, building a concrete capping beam that will connect these piles together into one structure, monitoring ground movement and then installing ground anchors if required to provide further stability, building a fence (hoarding) along the top of the beam, and creating a kerb and channel to direct water to catchpits in the carpark.

The previous work on site, over Christmas and New Year, was undertaken as ‘emergency work’. The next phase of work may also need to be undertaken as ‘emergency work’ as the construction timeframe is now moving quickly into the winter months and we need to ensure the stabilisation works effective over the summer period, are reinforced with additional stabilisation works for winter, which will also serve to further secure the site in the longer term.

As work further down the gully progresses, there will potentially be a need for further consultation and consenting.

We trust this does help explain some of the reasons why work on site may look like it has stalled – but we can assure you that it definitely has not. Please let us know if there are any other questions at rawene@aucklandcouncil.govt.nz

Next public meeting

Rawene Response Update – 17 March 2018

Contract Landscapes Limited has been on site this morning placing water-filled barriers along the top of headscarp (slip). The barriers are required to secure the site so that cars and pedestrians using the access lane are properly protected from the edge of the landslide. Once this is completed there is every intention of opening the lane so that people can access the rear of their businesses and utilise their private parking.

When will the access lane open?

The intention is that the lane should be open by Tuesday – and everything that is required to ensure this happens is being done. We will send another update to confirm the opening date, and let you know of any other new information, early next week.

Rawene Response Update – 1 March 2018

The weather forecast includes a high chance of rain over the next 10 days. As usual, we will take note of the forecasts and be keeping an eye on the monitoring systems on site. Please contact us if you see any unusual pooling or flooding during heavy rain at rawene@aucklandcouncil.govt.nz

Consultation on storm water works

Healthy Waters are currently preparing the design for a new temporary storm water pipe in the gully and will be contacting landowners on the eastern side of the site (Rawene Road landowners) regarding approvals to work on their land.

If your property lies within the boundary of the proposed works you will be contacted shortly. You will not be contacted unless the proposed route of the pipe goes through your land. Not all properties on the eastern side will be affected.

Property owners at the top of the landslide are also going to be contacted about approvals for works on their land, depending on the final design and mechanisms chosen. An example of these works might be ground anchors on property, and an example of the effects to expect from the works includes temporary noise sand vibration.

Activities on site

There is limited activity happening with only survey and monitoring activities being carried out on site while design and consultation is carried out for the next phase of remedial works. However, some hand augering is still being undertaken which is the process of drilling small holes, by hand, for sampling and monitoring.

As the programme for the next phase of the remediation becomes clear we will provide updates on the potential construction activities and timeframes. We are working towards being able to start the next phase of works in late March or early April.

New Safety signs

New safety signs are in the pipeline to replace the Auckland Transport signs on the exclusion fences at both the western and eastern areas of the site. With security guards no longer present on site, we ask that the signage and fence lines are respected as they are there for public safety.

More car parking spaces

We are currently working on re-opening more of the car park from Friday 2 March (or soon after) to provide between 10 and 20 more car parking spaces. Attempts are also being made to provide access to the private car parks behind the buildings at the top of the site either on the same day or shortly thereafter.

Also on car parking, we have received queries on when parking enforcement is to begin. Auckland Transport have noted that in regards to enforcement they did take a soft compliance approach for the first week and focussed on getting visibility with the local businesses and community rather than issuing infringements.

Auckland Transport confirmed that they patrolled the wider Highbury area three times last week and the carpark twice. They are now going to increase their focus on non-compliant vehicles and this will include attendance to the off-street carpark on Rawene Road.

We have updated our questions and answers section - Birkenhead slip - what you need to know - on OurAuckland.

Rawene Response Update – 19 February 2018

We are very keen to hear from you about your aspirations for the area, and how we can make the most of these unfortunate circumstances to improve the area. This early stage in the design process is the best point to provide your feedback, so please use this opportunity.

Please send your feedback by email to rawene@aucklandcouncil.govt.nz by the end of today - Tuesday 20th February.

Public feedback on design concepts

Concepts for the permanent solution are available here for the next 25 days. Whether the ideas presented through these options are feasible will depend on the cost (which has not yet been assessed), the consenting requirements, and your feedback.

This initial phase of feedback is designed to start a conversation with the local community about how you would like to see the area used in the future, which will help us steer the design process.

We will listen to all your concerns and ideas, balance them with the requirements of the landowners, residents, tenants, iwi, local board and other ratepayers, and technical considerations, with a goal to try and produce a result that will be great for Birkenhead and affordable for ratepayers.

We will continue to have further discussions on the design of a permanent solution for the Rawene site over the coming months in which you will have more opportunities to give feedback and to help us determine the best way forward.

Removal of unused sheet plies

The removal of unused sheet piles is scheduled to occur this morning (Tuesday 20^th February) with the car park closed from about 5.15 am. It is expected that this work will conclude at approximately 11.00am, (it may be open earlier depending on progress). There will be a site manager onsite to co-ordinate the closure and opening of the car park.

Please be advised that there will be noise early in the morning due to the trucks and loading machinery. We apologise for this inconvenience, but it is preferable to undertake this work early in the day to minimise disruption in the neighbourhood, as much as possible, during normal business hours.

Retaining wall maintenance

Maintenance work is underway on the retaining wall opposite the Rawene Centre on Rawene Road. Although not part of the Rawene project, we are keeping an eye on this work as it will be of interest to local residents. This work involves repairs to the retaining wall and an assessment of the stormwater system to check that it’s not been damaged by movement of the wall or by tree roots.

Borehole formation continues

Additional boreholes are still being formed on site. There is likely to be a helicopter used this week, (weather permitting), to drop some drilling equipment onto the site to assist with borehole formation. At this stage we cannot give an exact time for this, but it will only be during daylight hours and when the weather is suitable. The helicopter will also be used to move the drill rig around the site as required, again, apologies for any noise and disruption during this work.

New site safety signage

New safety signs have been ordered. These will replace the Auckland Transport signs on the exclusion fences at both the western and eastern areas of the site. The new signs will be Auckland Council signs and have the rawene@aucklandcouncil.govt.nz email address clearly visible and the Auckland Council contact phone number.

With security guards no longer present on site, we ask that the signage and fence lines are respected as they are there for public safety.

Future activity

With regards to physical works in the immediate future, only survey and monitoring activities will be carried out on site. As the design options are consulted upon and programme for the next phase of the remediation becomes clear we will provide updates on the potential construction activities and timeframes.

We are also currently working on options for the overland drainage to potentially remove the pumps and lay-flat pipes that are present on site.

Consultation as part of the preparation of resource consent documentation has begun, as outlined above, with the public meeting being the first opportunity for the community to see and talk about future remediation options. Please send any queries or comments to rawene@aucklandcouncil.govt.nz.

We are currently working on re-opening more of the car park once safety precautions have been finalised and put in place.

Rawene Response Update – 15 February 2018

There will be activity on site tomorrow as work to collect and remove some left over construction material from site is now scheduled for Friday 16th February.

The car park will need to be closed from 5:30am until approximately 11:30am that day (it may be open earlier depending on progress). There will be a site manager onsite from 5:15am to co-ordinate the closure and opening of the car park.

Removal of sheet piles

In addition, the removal of unused sheet piles is scheduled to occur next Tuesday morning, 20 February. Again, the car park will need to be closed. It is expected that this work will begin from 5:30am until approximately 11:00am that day (it may be open earlier depending on progress). There will be a site manager onsite to co-ordinate the closure and opening of the car park.

Helicopter equipment drop-off

Additional boreholes are still being formed on site. There is likely to be a helicopter used this week (weather permitting) to drop some drilling equipment (drill rig) onto the site to assist with borehole formation. At this stage we cannot give an exact time for this, but it will only be during daylight hours and when the weather is suitable. The helicopter will also be used to move the drill rig around the site as required. Again, apologies for any noise and disruption during this work

Tuesday's public meeting

A public meeting on the Rawene project was held on Tuesday 13 February 2018.

Thank you to all the members of the public and stakeholders – about 65 members of the local community - who attended the meeting for giving up their time to take part and provide feedback to on what they would like to see happen in the area over the coming months.

Some concepts for the permanent solution to the landslip were presented to give ideas and encourage feedback. Obviously the final choice will depend on public preferences, consenting requirements, and costs (which have not yet been assessed).

Slides from the public meeting are available here for the next 30 days.

Update on car parking

We are currently working on re-opening more of the car park once safety precautions have been finalised and put in place. Parking solutions were also put forward to make more spaces available on Mokoia and Huka Roads to try to alleviate some of the parking issues experienced by local businesses.

Resource consent preparation

Consultation as part of the preparation of resource consent documentation has begun, with the public meeting being the first opportunity for the community to see and talk about future remediation options.

We are very keen to hear feedback from local people about their aspirations for the area. We will listen to all your concerns and ideas, balance them with the requirements of the landowners, residents, tenants, iwi, local board and other ratepayers, and technical considerations, with a goal to try and produce an end product that will be great for Birkenhead and affordable for the ratepayers.

Please send your feedback by email to rawene@aucklandcouncil.govt.nz by Wednesday, 20 February.

This early stage in the design process – over the next week or so - is the best point to really change the direction of our work, so please use this opportunity.

The meeting concluded with a question and answer session, available here. We will continue to provide Q and A’s when we have information to share.

Rawene Response Update – 7 February 2018

Public meeting on Tuesday

The next public meeting on the Rawene Response project will be held on Tuesday 13 February, 6pm at the Rawene Centre, Birkenhead.

The Auckland Council project team will discuss with the local community the latest updates on work that has happened to date, the plan for the next few months, and to take questions from the community.

All are welcome. On arrival, please sign in at the table that will be in the reception area.

Please note the venue will be busy with a number of other activities and there is no car parking at the Rawene Centre, so please allow plenty of time.

Venue: The Auditorium, Rawene Centre, 33 Rawene Road, Birkenhead.

Outline of topics for discussion:

Update of emergency works
What’s next? We will discuss the next stages of design, the construction programme, and what to expect.
Parking: issues raised and feedback

Current work on site

Additional boreholes are still being formed on site to assist with developing potential options for the site. In additional to the boreholes survey work in the form of land based survey and drone surveys are being carried out.

Public consultation will be carried out prior to any remedial option being selected and we will discuss this further at the public meeting on Tuesday.

Security changes

As of Friday 2 February 2018, security guards are no longer on site but fencing around the perimeter will remain. We ask that the signage and fence lines are respected as they are there for public safety.

Future site activity

With regards to physical works in the immediate future, only survey and monitoring activities will be carried out on site.

As the design options are consulted upon and programme for the next phase of the remediation becomes clear we will provide updates on the potential construction activities and timeframes. We are also currently working on options for the overland drainage to potentially remove the pumps and lay-flat pipes that are present on site.

Preparation of resource consent documentation is underway for both the emergency works to date, and for potential future remediation options.

We are currently working on re-opening more of the car park once safety precautions have been finalised and put in place.

Updated questions and answers

New questions and answers have been added to our Birkenhead slip - what you need to know section here.

Rawene Response Update – 1 February 2018

Recent work on site has included the formation of some additional boreholes required to better understand the underlying soil and rock structures. That work will be used to inform the design options for a permanent engineering solution.

Other recent work on site was the removal of equipment, including a jet grout rig that previously fell into the slip, from the top of the site during earlier emergency work. We can confirm that the jet grout rig was successfully retrieved and has been taken off site.

Public meeting postponed

The public meeting scheduled for Friday 2nd February at 7pm has been postponed following a request from the Birkenhead Town Centre Association and the Kaipatiki Local Board. The chair of the local board asked, on behalf of the business association, that we delay the meeting to avoid disrupting Friday night shopping.

We are currently working on a new date that is likely to be within the next two weeks, and we will confirm that new date over the next day or two.

At the meeting we will be describing what's happened so far, discussing the plans for the next few months, and taking questions from the community.

Venue: The Auditorium, Rawene Centre, 33 Rawene Rd, Birkenhead - www.rawenecentre.org.nz

Outline of topics for discussion:

Update of emergency works
What next? Discussion on the next stages of design, construction programme, and what to expect
Parking: issues raised and feedback
Stormwater

Security changes

The security arrangements on site are changing. Following the completion of the emergency works and demobilisation of equipment required to achieve that, the two security guards on site were reduced to one.

We can now confirm that as of Friday 2 February 2018, there will be no further security guard on site. This is because there is presently not a lot happening on site to ensure that the public is aware of any hazards. Fencing will remain around the perimeter of the slip site.

Tonkin and Taylor appointment

There has been a consultant selected to investigate a number of future design options for the site. We are pleased to announce that Tonkin & Taylor have been successfully appointed to this role and have made a start. Initial options for the remediation of the site will be tabled at the public meeting to receive public feedback.

Parking availability

Council and Auckland Transport are closely looking at the parking availability on site. There are a number of options to possibly reinstate some, both, or either, public and private parking and we are hopeful that some of the parking will soon be available again.

We will keep you informed and are intending to cover this issue at the public meeting. As always, the parking availability will continue to fluctuate as works are progressed on site. Obviously, works are currently in a hiatus, and therefore the opportunity to re-open parking is available.

Rawene Response Update – 20 January 2018

A successful tender was appointed today from the three tenders we received for the design of the permanent remedial works.

The successful engineering firm will begin design work to provide a long-term resolution to the landslide early next week in order to start the consultation and consent process before the next phase of construction, which is likely to commence in April.

Public meeting on design consultation

A public meeting will be held in Birkenhead on Friday 2nd February at 7pm. This will be the start of the consultation on the design of permanent remedial works.

We will talk to the local community about the work that has happened so far, the plans for the next few months, and to take questions.

The designers will be in attendance to learn about the key local concerns, and will return at a later date with concepts and then detailed design options for consultation to ensure that the option selected best meets community needs. More details, including venue information for the public meeting, will follow.

Borehole drilling project

The Council has worked closely with the Mokoia Ridge Body Corp on the best way to carry out the borehole drilling project close to their building. Work will start on these boreholes on Tuesday or Wednesday next week, with a small amount of preparatory work on the Monday or Tuesday.

The boreholes are required to better understand the underlying soil and rock structures, and will inform the design of the permanent engineering solution.

Heavy machinery demobilisation

With the sheet piling work completed HiWay Geotechnical will be demobilising their heavy machinery from site. More physical work will be required in future, once an appropriate long-term solution for the slip has been agreed, but this is likely to require different equipment.

As equipment and materials are removed we will be progressively re-opening part of the car park as safely possible. We will be able to give more details of how much of the car park can be opened next week.

Site stability, access and monitoring

We will continue to make daily inspections of inclinometers, piezometers and survey markers as well as the site’s stability and our temporary stormwater diversions. There are also plans in place to undertake more intensive monitoring during bad weather.

In the interests of public safety, pedestrians and vehicles may not access private car parks via the slip road.

Please share the message that the land in the gully is unstable and contaminated. It is not safe to access, and we request that no one try to access this area even when no work is taking place.

For more information please read our Birkenhead slip - what you need to know section on OurAuckland here.

Rawene Response Update – 18 January 2018

Phase One of the project is complete with sheet pilling now in place.

Rain and wind over the next few days may stop work temporarily. Preparations have been made in advance of the bad weather, including a stormwater bund repair, and the checking of pumps in preparation for heavy rain. Building control staff will be checking the systems once rain starts.

Borehole work progressing

Works will progress on the additional boreholes required on the western side of the site towards the Mokoia Ridge Apartments either today (Thursday) or tomorrow (Friday), subject to the weather. These boreholes are required to better understand the underlying soil and rock structures, which will inform the design of the permanent engineering solution.

Heavy machinery demobilisation

HiWay Geotechnical will be demobilising their heavy machinery from site now that the sheet piling work has finished. More physical work will be required in future, once we have designed the appropriate solution to the slip, but this is likely to require different equipment.

We have reopened part of the car park to the public as far as possible. Obviously, for safety reasons, we may have to close it temporarily when we are moving heavy vehicles.

Site stability, access and monitoring

In the interests of public safety, it is no longer possible for pedestrians and vehicles to access private car parks via the slip road.

Please share the message that the land in the gully is unstable and contaminated. It is not safe to access, and we request that no one try to access this area even when no work is taking place.

Rawene Response Update – 15 January 2018

The weather forecast is rather variable for this week with a few spots of rain turning into more serious rain on Wednesday night which may stop work temporarily. However, works have been progressing well on site and the piling work is continuing.

Piling works

We will continue with the sheet piling and still expect to have a full row of piles installed by the end of tomorrow (Tuesday 16 February) if everything goes to plan over the next two days.

Some additional boreholes are now required on the western side of the site towards the Mokoia Ridge Apartments. We are hoping to drill these boreholes later this week, subject to approval from the Body Corporate of the Mokoia Ridge Apartments.

There is no indication that there is any immediate threat to the Mokoia Ridge Apartments. These boreholes are required to better understand the underlying soil and rock structures, which will inform the design of the permanent engineering solution.

Once the current row of sheet piles is complete there will be work happening to tidy up the site, and more physical work to maintain the stability.

Site access, stability, monitoring and safety

We have reopened part of the car park to the public as far as possible, so as to assist local businesses. For safety reasons, we may have to close it temporarily when we are moving heavy vehicles.

We are also making daily inspections of the site stability and our temporary stormwater diversions. There are also plans in place to undertake more intensive monitoring during bad weather.

In the interests of public safety, it is no longer possible for pedestrians and vehicles to access private car parks via the slip road.

Please share the message that the land in the gully is unstable and contaminated. It is not safe to access, and we request that no one try to access this area even when no work is taking place.

Stormwater emergency works

Because of all the loose soil at the crest and in the gully it’s important that we remove as much stormwater from the area as possible. The stormwater system at the crest is currently working well, but we can no longer allow it to immediately discharge into the gully in the way it did before the first slip occurred. This approach was reasonable when the gully was well vegetated, but will cause rapid erosion of the bare earth there at the moment.

As an interim measure we have installed a temporary pumping arrangement which splits the stormwater. Some goes to Rawene Road, and the rest along a flexible hose around the top of the valley. Both of these take the stormwater away from the areas of highest risk to locations where they shouldn’t cause significant problems in the short term. However, a longer term solution needs to be designed and built.

We will be commencing discussions with affected landowners in the very near future to identify how this temporary pipe can be installed in a way that satisfies their needs.

Permanent Design & Consultation

We are engaging a professional engineering design firm to undertake this investigation and permanent design work, with the intent that the majority of the re-stabilisation of this land will take place before winter. Some work will have to be carried over to the following year as there is unlikely to be time to complete it all before the wet winter weather makes working in the gully unsafe and inefficient.

It is likely that the permanent design will include some combination of earthworks and planting in the gully to stabilise the slipped material, and a more permanent structural solution at the crest to replace the sheet piles. No decisions have been made about the preferred design, and this decision making process will be undertaken in consultation with the Local Board, affected landowners and the local community to confirm their needs and expectations.

We plan to hold further public information evenings (date to be confirmed), including one-on-one discussion with the affected land owners. We will also be reporting to the Kaipatiki Local Board at its February Meeting.

Proposed stormwater works

Healthy Waters have indicated that the proposed storm water work at the bottom end of Rawene Road has been temporarily put on hold and no work is expected to re-commence before the end of February 2018. Healthy Waters will inform the nearby residents about the new time frames for the work when they have further information. Likewise, we will include any updates on this matter in these newsletters too.

New questions and answers have been added to our Birkenhead slip - what you need to know section here.

Rawene Response Update – 10 January 2018

The weather forecast is currently good, so we’re making the most of the fine weather and progressing well on site.

We will continue with the sheet piling this week, and expect to have a full row of piles installed by early next week.

Piling works

Once the current row of sheet piles is complete there will be work happening to tidy up the site, and more physical work maintain the stability. We will share more details about the timing and nature of these as soon as the details are confirmed.

Site access, stability, monitoring and safety

We have temporarily closed the car park to reduce the risk to the public using the car park caused by our heavy vehicle movements. This should allow the work to take place more efficiently so we can finish faster. We will re-open the car park on days when we aren’t moving heavy vehicles.

We will continue to monitor the inclinometers, piezometers and survey markers that we have installed to assess any future slope movement and give us reassurance that our stabilisation measures are working as designed. We are also making daily inspections of the site stability and our temporary stormwater diversions. We have plans in place to undertake more intensive monitoring during bad weather.

In the interests of public safety, it is no longer possible for pedestrians and vehicles to access private car parks via the slip road.

Please share the message that the land in the gully is unstable and contaminated. It is not safe to access, and we request that no one try to access this area even when no work is taking place.

New questions and answers have been added to our Birkenhead slip - what you need to know section here.

Rawene Response Update – 5 January 2018

The forecast bad weather is continuing, so only limited work took place today. It is not safe to lift sheet piles in strong winds, and we do not want to risk further slips by moving heavy equipment on site.

We have activated our contingency plan, which means there is full-time 24/7 observation, and regular surveying and monitoring of ground movement and groundwater until the bad weather ends. We are receiving regular, site-specific, weather updates from the MetService and using these to plan and prepare.

Footpath movement

As reported in the NZ Herald, a short section of footpath within the Birkenhead slip work site gave way at 4.30pm yesterday, and the path debris has moved downwards around one metre. It had been completely undermined over a number of weeks by the predicted repeated small movements. This meant the concrete path was bridging over a gap with no support. The area had been cordoned off for safety for a number of weeks.

Birkenhead slip_before — BEFORE | Footpath before heavy rainfall, Thursday 4 January, 10am.

Birkenhead slip_after — AFTER | Footpath following heavy rainfall on site, Thursday 4 January, 9pm.

We have inspected the area around the footpath and confirmed that no new cracks are forming behind it, and there are no indications of further regression at the moment. We undertook topographical surveys of the site yesterday morning (before the collapse) and again yesterday evening from 8pm after the movement to confirm that ground closer to the buildings has not moved. These surveys, along with our other monitoring, have confirmed that large scale movement is not taking place. We will continue with this monitoring today and tomorrow. It is likely that there will be further small slips caused by the wet weather over the coming days. We do not consider there to be any increase in risk to the buildings as a result of this localised movement.

Work on hold due to weather

Work is on hold until conditions are safe to continue. Our latest forecast suggests that the wind will not drop to levels that make sheet piling safe until late on Saturday. We will assess the ground conditions over the coming days and will re-start work as soon as it is safe, which may be over the weekend or Monday. If conditions are not safe for sheet piling on Saturday, we continue welding on site so that work can proceed more quickly next week.

Car park access and usage

We temporarily closed the car park yesterday to reduce the risk to the public using the car park caused by our heavy vehicle movements. We will re-open the car park whenever we aren’t moving heavy vehicles, but may re-close part of the site on Saturday and again next week. This should allow the work to take place more efficiently so we can finish faster.

Site stability, access and monitoring

In the interests of public safety, it is no longer possible for pedestrians and vehicles to access private car parks via the slip road.

Please share the message that the land in the gully is unstable and contaminated. It is not safe to access, and we request that no one try to access this area even when no work is taking place.

Sheet pile emergency works completion

Sheet piling will re-commence once the weather improves and the monitoring demonstrates that groundwater levels have returned to normal. We do not want to risk working in dangerous conditions, particularly if water in the slope makes it less stable. We expect that the weather will be significantly better next week, and that the majority of our sheet piles will be installed then. We currently anticipate that all sheet piles will be installed by 16 January.

Stormwater emergency works

A permanent piped network is likely to be the end result, but will take some time – and require full stabilisation of the ground – before it can be installed. In the interim a more reliable temporary pipeline is being planned around the eastern flanks of the gully. We will be commencing discussions with affected landowners in the very near future to identify how this temporary pipe can be installed in a way that satisfies their needs.

Permanent design and consultation

Ground investigations in the body of the slip are required to design a permanent solution. These can only be started safely once the crest is stabilised with the emergency works (sheet piles) and the stormwater control down the gully has been improved. We are engaging a professional engineering design firm to undertake this investigation and permanent design work, with the intent that the majority of the re-stabilisation of this land will take place before winter. It is likely that some work will have to be carried over to the following year as there is unlikely to be time to complete it all before the wet winter weather makes working in the gully unsafe and inefficient.

It is likely that the permanent design will include some combination of earthworks and planting in the gully to stabilise the slipped material, and a more permanent structural solution at the crest to replace the sheet piles. No decisions have been made about the preferred design, and this decision making process will be undertaken in consultation with the local board, affected landowners and the local community to confirm their needs and expectations.

We plan to hold further public information evenings (next date to be confirmed), including one-on-one discussion with the affected land owners. We will also be reporting to the Kaipatiki Local Board at its February meeting.

Rawene Response Update – 4 January 2018

Work stopped due to weather

The forecast bad weather has arrived, so most work on site was stopped at about 1pm today. It is not safe to lift sheet piles in strong winds, and we do not want to risk further slips by moving heavy equipment on site.

We have activated our contingency plan, which means there will be full-time 24/7 observations, and surveying and monitoring of ground movement and groundwater.

We are receiving regular, site-specific, weather updates from the MetService and using these to plan and prepare.

Work is on hold until conditions are safe to continue. This might be Friday, but is more likely to be Saturday. We will assess the ground conditions over the coming days and will re-start work as soon as it is safe, which may be over the weekend or possibly not until Monday.

Car park access

We temporarily closed the car park yesterday to reduce any risk to the public caused by our heavy vehicles using the car park. We will re-open the car park whenever we are not moving heavy vehicles, but may re-close it for part of the weekend (if work is allowed) and part of next week. This should allow the work to take place more efficiently so we can finish faster.

Site stability

We will continue to monitor the inclinometers, piezometers and survey markers that we have installed to assess any future slope movement and give reassurance that our stabilisation measures are working as designed. We are also making daily inspections of the site stability and our temporary stormwater diversions. We have plans in place to undertake more intensive monitoring during bad weather.

Work programme

Sheet piling will re-commence once the weather improves and the monitoring demonstrates that groundwater levels have returned to normal. We do not want to risk working in dangerous conditions, particularly if water on the slope makes it less stable. We expect that the weather will be significantly better next week, and that the majority of our sheet piles will be installed then.

Site safety and access

At this stage, it is still too early to establish what the causes of the slips are. Auckland Council engineers and technical specialists are continuing with investigations, but this work is complicated by the instability of the site. Our primary focus is ensuring the site safety for workers, the public and adjacent properties.

In the interests of public safety, it is no longer possible for pedestrians and vehicles to access private car parks via the slip road.

Please share the message that the land in the gully is unstable and contaminated. It is not safe to access, and we request that no one try to access this area even when no work is taking place.

Rawene Response Update – 3 January

Weather watch

We’re watching the weather forecasts very closely at the moment and using regular, site-specific weather updates from MetService to plan our work for the next few days.

Heavy rain, wind and lightning forecast for the next few days (potentially starting from Thursday 4 January) may affect work on the site.

Work programme – may be affected by weather

Work recommenced on Tuesday 2 January as planned. Welding of sheet piles and the preparation of areas for their installation are the main activities on site. We have slightly extended the closed area of car park to allow the welding to take place efficiently.

Sheet piling will re-commence on Thursday 4 January (weather permitting) once we have prepared the next area for installation. There is a high risk that this will be delayed, possibly until next week, if the weather is bad. We do not want to risk working in dangerous conditions, particularly if water on the slope makes it less stable. We expect that the weather will be significantly better next week, and that the majority of our sheet piles will be installed then.

Site monitoring and stability

Safety and public access

In the interests of public safety, it is no longer possible for pedestrians and vehicles to access private car parks via the slip road.

Please share the message that the land in the gully is unstable and contaminated. It is not safe to access, and we request that no one try to access this area even when no work is taking place.

Rawene Response Update – 1 January

Adjustment to work schedule (weather)

To make progress before the potential heavy rain that is forecast for Friday, we have re-started work a day earlier than originally proposed. We will be welding sheet piles into appropriate lengths and will continue with our service locations.

We may have to slightly extend the area of car park closed to allow the welding to take place efficiently. If you have any concerns about how this might affect you or your business please email us.

Sheet piling

Sheet piling will re-commence on Thursday 4 January (weather permitting) once we have prepared the next area for installation.

Site stability, access and safety

In the interests of public safety, it is no longer possible for pedestrians and vehicles to access private car parks via the slip road.

Please share the message that the land in the gully is unstable and contaminated. It is not safe to access, and we request that no one try to access this area even when no work is taking place.

Rawene Response Update – 29 December

We had originally planned to work Wednesday to Friday this week. Since the weather is currently good, and bad weather is forecast for next week, we will also work on Saturday 30 December (tomorrow) to make progress while the weather is suitable. If you have any concerns about how this might affect you or your business please email us.

After some delays caused by unmarked buried services, sheet piling is progressing well.

A new permanent gas pipeline supplying the Mokoia Road shops has been installed set well back from the slip, and the original pipe near the slip face has been decommissioned.

Next week’s works

Work will continue next week on the emergency stabilisation with sheet piles. Work is planned to take place on 3-5 January, although days may vary depending on the weather.

All work over the Christmas and New Year period and will be undertaken carefully and slowly, with full-time supervision.

Site safety and exclusion zones

In the interests of public safety, it is no longer possible for pedestrians and vehicles to access private car parks via the slip road.

Please share the message that the land in the gully is unstable and contaminated. It is not safe to access, and we request that no one try to access this area even when no work is taking place.

Rawene Response Update – 27 December

It has become apparent that additional security, in the way of fencing, may be required at the western access of the site. We will let you know when works may commence on this.

There was some rain on the morning of 26 December. Pumps on site will be used to alleviate any run-off associated with rain.

Sheet piling

Our sheet piling trial last week was successful and preparation for the installation of sheet panels has commenced. This work is likely to be noisy and there will be vibration for properties adjacent to, and surrounding, the Rawene site. The temporary sheet pile wall will be set a few metres back from the slip.

Our external experts have recommended that we do this to reduce the risk of the slip regressing further into the private land at the crest. Because regression of this sort could be triggered by very heavy rainfall, it is important that we move quickly to stabilise the area. As well as stabilising the land, this temporary wall has been designed to take the load from the crane to allow more permanent remedial works to take place. All of this activity will be carefully monitored.

Site works over the holiday period

All work over the Christmas and New Year period and will be undertaken carefully and slowly, with full-time geotechnical supervision. No work is intended to take place on public holidays and weekends to minimise the disruption to local businesses and residents – work will likely occur on 27-29 December and 3-5 January.

Gas supply temporary outages

For safety purposes, the gas supply will need to be turned off to some properties before the western half of the sheet pile wall can be installed. We estimate this will be required by Thursday 28 December. Local residents who may be affected by this have been advised in advance and we will arrange an alternative supply for them as required. If you think you will be affected by this and have not already been contacted directly, please let us know.

Site safety and exclusion zones

In the interests of public safety, it is no longer possible for pedestrians and vehicles to access private car parks via the slip road.

Please share the message that the land in the gully is unstable and contaminated. It is not safe to access, and we request that no one try to access this area even when no work is taking place.

Rawene Response Update - 22 December

The sheet piling trial earlier this week was successful, and our designer reports that vibration limits were within tolerable levels for buildings. This means that installation of the sheet panels can commence on Wednesday 27 December.

This work is likely to be noisy and there will be vibration for properties adjacent to, and surrounding, the Rawene site. All of this activity will be carefully monitored.

It is important to be aware that people are much more sensitive to vibration than buildings are, so it is likely that vibrations will be felt as these works take place. Structural engineering assessments have been made of the adjacent buildings to identify any particularly sensitive structures and we have already put in temporary measures to keep them safe.

Site works over the holiday period

Work will continue over the Christmas and New Year period and will be undertaken carefully and slowly, with full-time geotechnical supervision.

No work is intended to take place on public holidays and weekends to minimise the disruption to local businesses and residents, this includes no activity on Christmas Day or Boxing Day meaning that work will likely occur on 27-29 December and 3-5 January.

Future site activity

Now that the trial stage has been successfully passed, we are finalising the details of the design, (in particular how we work around buried services), and are on track to begin work on the 27 December.

We will start installing a temporary sheet pile wall set a few metres back from the slip. Our external experts have recommended that we do this to reduce the risk of the slip regressing further into the private land at the crest.

Because regression of this sort could be triggered by very heavy rainfall, it is important that we move quickly to stabilise the area. As well as stabilising the land, this temporary wall has been designed to take the load from the crane to allow more permanent remedial works to take place.

For safety purposes, the gas supply will need to be turned off to some properties before sheet piles can be installed by Thursday 28 December. Local residents are being advised in advance and we will work with those affected on an alternative gas supply.

Safety exclusion zones

In the interests of public safety, it is no longer possible for pedestrians and vehicles to access private car parks via the slip road.

The land in the gully is unstable and contaminated. It is not safe to access, and we request that no one try to access this area even when no work is taking place.

Rawene Response Update – 19 December

Following Auckland Transport’s emergency response to address the immediate effects of the slips, work on the Rawene Road site has transitioned from the ‘emergency response’ to the ‘recovery’ stage.

Auckland Council will now take the lead role, working with Auckland Transport and other council agencies to ensure the safety and stability of the site and to co-ordinate future remedial works.

Activities on the Rawene site

The car park was closed last Friday morning (15 December) to allow a crane to be brought in after we received engineering advice that the site was safe to take the load.

This had originally been planned to take place over the weekend but, after feedback from local businesses, we changed the dates to be on Friday and Monday to reduce disruption to shoppers on the busy pre-Christmas weekend.

Sheet pilling to be installed

The sheet piles will be installed by high-frequency vibration. This method was selected as it has low effect on the stability of land or adjacent structures.

A trial installation of a single sheet pile was undertaken today to check the level of vibrations caused. It was monitored by three vibration monitors set 3m, 5m and 10m from the sheet pile, and preliminary results showed that the vibrations were within acceptable limits.

The vibration and engineering experts will analyse these results over the next few days, before further work takes place, to ensure that we can continue safely.

We have finished installing the inclinometers, piezometers and survey markers that will allow us to assess any future slope movement and give reassurance that our stabilisation measures are working as designed.

In addition, external technical experts from Opus have been engaged to investigate and design remedial works. These will be underway shortly.

Future site activity

If the vibration assessments are satisfactory, we intend to start installing a temporary sheet pile wall set a few metres back from the slip.

As well as stabilising the land, this temporary wall has been designed to take the load from the crane to allow more permanent remedial works to take place. These works will be undertaken carefully and slowly, with full-time geotechnical supervision, over the Christmas and New Year period.

Causes of the slip

At this stage, it is too early to establish what the causes of the slips are. Auckland Council engineers and technical specialists are continuing with investigations, but this work is complicated by the instability of the site. Our primary focus is ensuring the site safety for workers, the public and adjacent properties.

Safety exclusion zones

In the interests of public safety, it is no longer possible for pedestrians and vehicles to access private car parks via the slip road.

The land in the gully is also unstable and contaminated. It is not safe to access, and we request that no one try to access this area even when no work is taking place.