Source: Auckland Council
Revised timeline for GHD assessment
GHD has nearly finished conducting assessments of affected properties in the Piha and Karekare areas. GHD’s assessment included geotechnical site inspections and the assessment of damage from landslides.
As part of the ongoing geotech fieldwork, drone surveys will be undertaken for properties with restricted access from the week starting Monday 18 September 2023. We have been liaising with landowners of affected properties to obtain permission prior to flying the drones. We would like to express our thanks to the homeowners who have given us permission to undertake these surveys. We do encourage your cooperation as it enables us to provide the most comprehensive geotechnical assessment possible, while helping us keep the programme of work on track and avoid further delays. Final permission for these drone surveys can be given up until Monday morning, 18 September.
Over the next two weeks, GHD will revisit some properties at both Piha and Karekare to gain additional technical information, and be present for some of the drone surveys where there are access restrictions. Geotechnical reporting will continue at the same time for the remaining affected properties.
Drone surveys and orthomosaic imagery are very useful for geotechnical assessments as they can provide a detailed view of the entire site, provide high-resolution aerial imagery and topographic data. Orthomosaic images stitch together multiple individual photos (“orthophotos”) which are then overlapped to capture a comprehensive view of an area. Orthophotos can provide site overviews, precise measurements of landforms and features and terrain analysis, to create digital elevation and surface models for geotechnical analysis.
Timeline for release of GHD’s draft reports
Unlike Muriwai which had two large escarpments and associated large scale instability, the landslides in Piha and Karekare consist of numerous localised landslips and land instability. Because of this, it is more appropriate for GHD to produce multiple reports – one per landslide or area of instability. In some cases, reports will cover single properties, while others will include multiple adjacent properties.
Due to the number of reports being produced, we will be releasing GHD’s draft reporting with property owners in Piha and Karekare in tranches, as the reports become ready. This approach means that individual property owners will get their information as soon as practically possible, rather than waiting for every report to be completed.
Affected property owners will be emailed a draft geotechnical report and their initial property category, and will have the opportunity to provide feedback and discuss the report one-on-one with a geotechnical expert.
We will be contacting property owners directly over the next week to advise them of next steps, including whether they are impacted by GHD study and, if so, when they will receive a draft report and invites for follow-up discussions with technical experts.
Auckland Council will use GHD’s reports to inform decisions on final risk categorisation, as well as reviewing RBA placards.
Timeline for upcoming engagements
Community meetings, Saturday 23 September
The purpose of these meetings is to provide updates on the categorisation and risk assessment processes, and provide an update on the progress of the GHD study. At this meeting, we will explain how the placard review process will work once the geotechnical findings are available, so the next steps are clear for you.
All members of the Karekare and Piha communities are welcome to attend these meetings.
At each of these meetings, Auckland Council Head of Resilience Ross Roberts will discuss the geotechnical reports and answer any questions you may have.
Piha community meeting – 10am – noon, Barnett Hall, 2 North Piha Road, Piha
Karekare community meeting – 2–4pm, Karekare Surf Club, 34 Watchmans Road, Karekare
Release of GHD reports and initial property category
Reports will be released in clusters based on when they are completed by GHD. These clusters are:
Exact dates will be confirmed directly to affected property owners once confirmed.
GHD assessment area
The assessment areas are shown in the maps below.
Piha assessment area:
