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Chris Dolley introduced the item, about
the Council’s emergency response to Cyclone Gabrielle. Key points of
the presentation by Chris Dolley, Katrina Brunton, Susie Young, Iain Maxwell
and Pieri Munro covered:
· Massive event with
widespread and significant damage. Recorded rainfall in many areas was well
beyond the amounts forecast by Metservice, amounts, intensity and duration.
This was on top of what was already one of the wettest summer since records
began in Hawke’s Bay.
· Stopbank breaches
occurred as the result of erosion, after the stopbank was over-topped by the
velocity of water and debris in the channel. Stopbanks are built to a
standard, e.g. 1 in 100 year standard in Central Hawke’s Bay and
Heretaunga Plains schemes.
· There is a view amongst
technical staff that a risk of under-reporting of rainfall exists due to the
high winds and potential for gauges to have not collected all of what fell
(wind blew it away from the guage).
· Progressed from local
state of emergency declared in Wairoa first, to national state of emergency
· Eight lives lost in HB
and massive damage to property (over 1000 red & orange stickered
properties), highways, bridges, railway lines, power and communication
networks, wastewater treatment and drinking water networks, and production
(farms, orchards) and recreational land.
· At least two reviews will
be undertaken. An ‘infrastructure (scheme)’ review that looks at
how the flood protection schemes performed, the flood warning network, pump
stations etc. which will include a peer review and inform the ‘build
back better’ work programme. There will also be a review of how all
agencies involved in the emergency response responded.
· Rapid repair team working
to carry out emergency repairs to stopbanks, first with temporary bunding
while permanent repairs are carried out.
· 99% of the rain and river
level monitoring sites have been restored and staff are working on the last
site today
· HBRC has taken on
regional coordination of rural waste disposal for silt, wood, posts and wire
and animal carcasses (will be completed by end of this week)
· Regional disaster relief trust
has been set up and HBRC will be the administration agency for that fund.
· At any one time there are
15-20% of HBRC staff at the Group Emergency Coordination Centre in Hastings
involved in the response.
· Council edge protection
trees included in wood debris, is used to control the velocity of water at
the edges to protect stopbanks from erosion. Damming of wood debris against
bridges (Waiohiki bridge near EIT & Omahu at Fernhill bridge) reviews
will be modelled to take into account when looking at bridge heights for
rebuilding bridges.
· Engineered solutions
(stopbanks) are always built to a standard and there is a risk that the level
of service is exceeded by an event which isn’t a failure of the system.
· In 2015 Council made
decision to upgrade the Heretaunga scheme from 1 in 100 years to 1 in 500
years, and co-funding was provided by central government during Covid,
including impact of failure risk assessments, for Taradale (completed), Moteo
(finalising consent) and upper Ngaruroro in Ngatarawa (contracted works
commenced October 2022) area as prioritised as highest risks to population
and lifelines.
· Taradale built to 1 in
500 year standard with freeboard but was slightly overtopping in places, and
why evacuations of parts of Taradale were carried out.
· Esk and Tangoio not
covered in today’s presentation, both of which have maintenance schemes
providing a very low level of protection. HBRC responsibilities in those
areas include making hazard profiles known and submitting to city and
district council consenting processes advising against building in hazard
prone areas.
· After Cyclone Bola there
was a flood scheme designed but due to ‘affordability’ issues
(schemes are funded by the communities that benefit from them) it
wasn’t implemented.
· Discussions with central
government need to include suitable land use in high risk areas as well as
funding for engineered flood protection schemes.
· Without doubt there is a
lot of wood debris and more work will be done to understand and model impacts
of volumes of wood on bridges and the stopbanks.
· Where wood needs to be
removed to access stopbank repairs or is threatening bridges HBRC is carrying
out that work. Responsibility for clearing wood out of waterways is the
responsibility of the bridge or land owner where the wood is.
· Rapid rebuild workstream
(160 people) carrying out stopbank repairs (5km breaches and 26km weakened)
with Allen Road, Taradale and Maraenui Golf Course repairs completed.
· An HBRC team has been
stood up to coordinate solid waste collection and disposal, working with
central government to find funding sources.
· Collaborating with TLAs
for collection wood waste, which is being taken to Whakatu for chipping,
stockpiling the wood chips until such time as the wood chips can be taken to
Panpac for use in their furnace when it is back running. Staff are connected
into the ‘slash’ review by central government.
· Working with TLAs to
develop capacity at the landfill because the region does not have the
capacity to deal with the volumes of waste.
· Working on options, with
ministry officials, for disposing of posts (tanalised), wire and netting from
orchards. Burning tanalised wood is prohibited.
· Napier, Hastings and HBRC
working collaboratively on sites for depositing silt from rural areas. TAs
currently don’t have capacity to collect residential silt. Sampling
has shown silt is mostly not contaminated, with one known contaminated site
being Awatoto industrial area.
· Contracts issued for
disposal of silt and wood primarily around HBRC flood infrastructure and open
spaces, and the costs are not recoverable from anywhere at the moment. EQC
will assist, where people are insured, with removal of residential silt. If
removal of silt from Tangoio and Esk is to happen central government would
have to provide funding.
Councillor
Martin Williams left the meeting at 2.40pm
· Warnings and alerts are
issued on the basis of known or predicted information (forecasts) by the
Civil Defence Group Controller and delivered via cellphone. Parts of Esk
Valley known to be at risk of flooding were asked to evacuate on the Monday
night by NZ Police going door to door.
· Based on forecasts, flood
engineers work to model predict the response of the catchments. In this
event, it was concluded that the flood schemes would be tested but would be
within the levels of service provided. Part of the assessment identified Esk Valley
properties at risk and those properties were advised to evacuate.
· HBRC is not going to be
clearing land but is offering to collect and transport silt and help
facilitate the opportunity for those who can to save their trees, for
example.
· Any review or enquiry
will definitely look for lessons learned and how systems and processes can be
improved.
Councillor
Di Roadley left the meeting at 3.00pm
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