BEFORE THE ENVIRONMENT COURT I MUA I TE KOOTI TAIAO O AOTEAROA
ENV-2018-AKL-000078
IN THE MATTER of the Resource Management
Act 1991 (RMA)
AND
IN THE MATTER of the direct referral of
applications for resource
consent for the necessary
infrastructure and related
activities associated with
holding the America's Cup in
Auckland
BETWEEN PANUKU DEVELOPMENTAUCKLAND
Applicant
AND AUCKLAND COUNCIL
Regulatory Authority
EVIDENCE OF STEPHEN JOHN PRIESTLEY ON BEHALF OF PANUKU DEVELOPMENT AUCKLAND
(INFRASTRUCTURE AND COASTAL PROCESSES) 7 AUGUST 2018
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1. QUALIFICATIONS AND EXPERIENCE
1.1 My full name is Stephen John Priestley. I am a Senior Technical Director with Beca
Limited in Auckland.
Qualifications and Experience
1.2 I have a Bachelor of Engineering with First Class Honours in Civil Engineering from the
University of Auckland and a Masters of Engineering Science from the University of New
South Wales.
1.3 I am a member of the New Zealand Hydrological Society and the New Zealand Coastal
Society. I am a Chartered Professional Engineer and a Fellow of Engineering New
Zealand. I have worked on major infrastructure projects for 39 years in New Zealand,
Australia, the United Kingdom, Central America and the Asia-Pacific region.
1.4 The main focus of my project experience has been in port and coastal projects, water
management and land development. My relevant experience includes:
a) Managing many of Ports of Auckland Limited's (POAL) resource consent
applications and projects including the Fergusson Container Terminal
extension, the Wiri Inland Container Terminal development, the deepening of
the Rangitoto Channel shipping lane and other dredging and disposal projects,
wharf repairs and upgrades and stormwater management.
b) Assessment of infrastructure and contamination issues for Development
Auckland – Panuku’s Western Reclamation and later engineering input and
construction monitoring of its Wynyard Quarter development.
c) Resource consent applications and the design and construction of marine works
for Fisherman's Wharf and the Viaduct Basin (formerly known as the America's
Cup Harbour, competed in 2000).
d) Engineering studies and the design of marine projects including:
i. Chelsea Wharf;
ii. The Port of Napier;
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iii. Northport berth extensions;
iv. Wharf repairs at the Port of Timaru;
v. Dredging at the Port of Lyttelton;
vi. The Northern Regional Boat Ramp for the Western Bay of Plenty
District Council;
vii. Kings Wharf in Suva, Fiji; and
viii. The Victoria Desalination Plant in Melbourne, Australia.
e) The design of marinas (e.g. Westhaven, Pine Harbour, Gulf Harbour,
Bayswater, Whitianga, Mercury Island and the Silo Park superyacht marina).
f) Creation of beaches and renourishment projects for Westshore in Hawkes Bay,
Clifton Beach in Hawkes Bay, Sulphur Point in Tauranga, Mission Bay,
Kohimaramara and St. Heliers Beaches in Auckland’s eastern suburbs.
g) Declamation associated with the removal of the oxidation ponds at Mangere
and 5km of coastal restoration within the Manukau Harbour.
h) Project reviewer of coastal engineering for the North Canterbury Transport
Infrastructure Recovery (NCTIR) at Kaikoura.
i) Preparation of ARC’s TP10 “Stormwater Treatment Devices: Design Guideline
Manual” (1992).
j) Preparation of ARC’s TP108 “Guidelines for stormwater runoff modelling in the
Auckland Region” (1998).
k) Preparation of ARC's TP130 "Coastal Erosion Management Manual" (2000).
1.5 In addition to the above project experience, I have acted as an Independent
Commissioner and the Minister of Conservation's representative at resource consent
application and plan change hearings. I have previously presented expert evidence to
Commission hearings, Arbitrations, the Environment Court, the EPA Board of Enquiry,
and the High Court.
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1.6 I attended the Coastal, Stormwater, Geotech and Engineering conferencing on 31 July 2018 and was involved in the development of the Joint Witness Statement (JWS)
prepared and agreed at this conference. There were no matters of disagreement
between the experts.
1.7 I advise that I have read the Code of Conduct for Expert Witnesses contained in the
Environment Court Practice Note 2014 and have complied with it in preparing this
evidence. I confirm that the issues addressed in this evidence are within my area of
expertise and I have not omitted material facts known to me that might alter or detract
from my evidence.
2. SCOPE OF EVIDENCE
2.1 I have been engaged by Panuku Development Auckland (Panuku) to undertake
(amongst other things) the preliminary engineering design of the America’s Cup Infrastructure (the Project), and an assessment of the coastal processes effects of the
Project, for which resource consent applications have been lodged with the Environment
Court. My evidence describes the main elements of the engineering design and the
coastal processes assessment and its findings.
2.2 This evidence highlights the key points from the following technical reports, which formed part of the Assessment of Environmental Effects (AEE) (CBD Vol A, CB4, page 81).
Where appropriate, this evidence updates my original assessment and
recommendations. With the exception of any updates noted in this evidence, I confirm
the content and accuracy of these earlier reports:
a) America’s Cup, Wynyard Hobson: Coastal Processes and Dredging Technical
Report (CBD Vol A, CB17, page 913);
b) America’s Cup, Wynyard Hobson: Physical Infrastructure Technical Report
(CBD Vol A, CB10, page 586);
c) America’s Cup, Wynyard Hobson: Geotechnical Report (CBD Vol A, CB30,
page 1863);
d) America’s Cup, Wynyard Hobson: Stormwater and Services Technical Report
(CBD Vol A, CB33, page 2145); and
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e) America’s Cup, Wynyard Hobson: Engineering Concept Drawings (3233847
series) (CBD Vol A, CB45, page 2510).
2.3 My evidence covers the following matters:
a) Infrastructure design, including geotechnical aspects;
b) Stormwater and services;
c) Coastal processes, including the effects of dredging;
d) Changes in the concept design since lodgement;
e) Comments on the Auckland Council Report;
f) Comments on submissions; and
g) Conclusions.
2.4 I have been involved in expert conferencing on matters related to infrastructure and
coastal processes. The outcome of that process was that there was no disagreement
between the experts.
3. SUMMARY OF EVIDENCE
Landside Works
3.1 The landside works will contain five syndicate bases, a new road access, an access and
carpark area to the rear of the syndicates and a landscape area. They will be located on
Wynyard Point and cover an area of some 25 ha. The majority of the area will be elevated
above existing ground level and comprise paved areas and be fully serviced.
3.2 Although the earthworks (for excavation) are of a small scale, there will be adverse
environmental effects related to earthwork activities in contaminated soils. Monitoring
and an active response strategy will be important to mitigating these adverse effects.
These requirements are set out in the proposed conditions of consent.
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Maritime Works
3.3 The maritime works comprise new wharves (piles and deck), piled breakwaters,
dredging, pontoons and underwharf services. These structures will occupy some 2 ha of the Coastal Marine Area (CMA) and involve about 73,000 m3 of dredging and piling
works.
3.4 Short term adverse effects relate to the construction including noise and vibration,
lighting (addressed by Craig Fitzgerald and John McKensey respectively), and
sedimentation. Again, monitoring and an active response strategy will be important to
mitigating these adverse effects. These requirements are set out in the proposed
conditions of consent. Longer term related adverse effects relate to coastal processes,
as discussed below.
Services
3.5 All areas related to the syndicate bases will have stormwater collection and treatment in
accordance with the Auckland Unitary Plan. This will include fully complying with the
provisions for Industrial and Trade Activities (ITA) (CBD Vol E, CB187, page 4657) and
Hazardous Substances (HS) (CBD Vol E, CB186, page 4643).
3.6 Other services include water supply, wastewater, power, and communications. Services
on land will be in underground trenches. Services in the CMA will be routed in underwharf
galleries. Working with the Service Providers, it has been established that there is
sufficient capacity in either their supply or acceptance of a service connection.
Coastal Processes
3.7 The proposed layout represents a balance between meeting the tranquillity criteria for
the berthing areas and unduly impacting on the flushing times for the basins. The layout
will change tidal currents, basin flushing times, wave/wake reflection and sedimentation.
3.8 The effects of the proposed development on tidal flows and currents are considered to
be no more than minor because of the localised extent and limited actual scale of these
changes.
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3.9 Basin flushing times when the Project is constructed are longer but predominately tend
to stay in similar “good” / “fair “categories as the existing flushing. The exception is the
mid-Inner Viaduct Harbour where it changes from “good” to “fair”. Changes in the flushing
times represent a moderate/minor adverse change compared with the beneficial change
of berth tranquillity for the Outer Viaduct Harbour and Wynyard Wharf South water space.
3.10 In general terms, there will be a similar or slightly improved degree of reflection outside
the Project Area, in Freemans Bay and the Maritime Museum basin. Any increase in
local maximum wave height is typically less than 0.1m for the proposed layout. Any
potential adverse effects relating to this small increase are expected to be difficult to
detect as the sea state is relatively energetic under present conditions.
3.11 Sedimentation will increase in the more tranquil basins/harbours, but at a similar scale
to existing sedimentation rates. Potential adverse effects are therefore expected to be
minor and to be managed using existing maintenance dredging practices in a similar
manner to present sedimentation.
3.12 Dredging will create sediment plumes which become more diffuse away from the
dredger. Monitoring of sediment plumes on previous dredging campaigns has
demonstrated that the effects are minor.
3.13 Coastal hazards and climate change adaptation have been considered in the design of
the Project.
3.14 For the Wynyard Hobson project, the main beneficial effect will be the increased calm
waterspace for the berthing of vessels.
4. RELEVANT FACTS AND CONTEXT
4.1 In this statement of evidence, I do not repeat the project description and refer to the
summary of the application in the evidence of Mr Rod Marler (Panuku).
4.2 I have been intimately involved in this Project since October 2017. I have had direct
contact with Panuku on a day-to-day basis to discuss developments and resolve issues
as they have arisen. My involvement has included:
a) Review of layout options at different locations;
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b) Planning and presenting concept layouts of the Wynyard Basin option;
c) Planning and presenting concept layouts of the Fishing and Ferry Industry
Relocation Facility;
d) Planning and presenting concept layouts of the Wynyard Hobson option (i.e. the
basis of this application);
e) Attendance at weekly team and design meetings;
f) Attendance at meetings with Auckland Council regulatory team;
g) Overview reviewer of the technical reports prepared by Beca Ltd; and
h) Reviewer of marine works for the Alliance design team.
4.3 As part of the overall coastal processes assessment, Beca Ltd and Tonkin and Taylor
Ltd worked together on various aspects of the coastal processes, for example, in
modelling of the tidal flushing. In addition, Cardno Consultants of Australia were
commissioned to numerically model the wave and wake climate within the Project. I wrote
the briefs for this modelling work and reviewed the results which I consider to reasonably
represent the actual field conditions. The work was carried out under my supervision and
I am comfortable with the accuracy of the models. I have relied on the outcome of these
model studies in determining the likely effects on coastal processes and their reports are
included in “America’s Cup, Wynyard Hobson: Coastal Processes and Dredging
Technical Report” (CBD Vol A, CB17 – 20).
4.4 As part of this Project, site specific studies of the seabed sediment were undertaken in
order to characterise the material. This work was undertaken by a specialist sediment
scientist, Mr Paul Kennedy, who has prepared a statement of evidence that addresses
these matters. I have relied on Mr Kennedy’s evidence in assessing the effects of
dredging.
4.5 My evidence includes some discussion on the geotechnical conditions of the site. I am
not an expert geotechnical engineer but have managed and been involved in many
projects requiring assessment of complex geotechnical conditions, both on land and in
marine areas. For this evidence, I have relied on information contained in the
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geotechnical report (CBD Vol A, CB30, page 1863), including historical investigations,
and discussions with geotechnical engineering colleagues on the project.
4.6 My evidence does not cover the syndicate buildings, which are addressed in evidence
of Mr Gordon Moller. Construction methodologies and timeframes are addressed by Mr
Kurt Grant.
Site Description - Landside
4.7 The location of the physical landside infrastructure works is within Wynyard Point, which
is shown in the aerial photo below marked Figure 1. Wynyard Point extends north from
the north-western corner of the Wynyard Quarter, and is approximately 530m long by
200m wide. The reclamations are bordered by seawalls and piled, reinforced concrete
wharves. The seawalls range from recent post and panel seawalls at North Wharf
(completed in 2009) and Viaduct Harbour (2000) to the Wynyard Point rock bunds dating
from the 1920s.
Figure 1: Aerial photo showing the Wynyard Quarter
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4.8 Much of the land contains contaminated material from historical activities. This is
discussed in detail in the evidence of Mr Phillip Ware.
4.9 Bases C-G are to be located on Wynyard Point, bound by Hamer Street on the western
side, and by existing bulk liquid storage facilities (a tank farm) to the north. The BST and
Stolthaven South tank farms will cease and the sites will be cleared and made available
for the development of base infrastructure. To provide connectivity between the
syndicate base buildings and the water loadout area, a section of Brigham Street
(approximately 236m) will be stopped and incorporated into the base yard areas.
Site Description - Habourside
4.10 Waitematā Harbour is a large drowned valley with numerous arms and extends some 25
kilometres inland from the harbour entrance at North Head. The high tide area of the
harbour is some 180km2 and the volume is approximately 460 million m3. The harbour
catchment, or area of land draining into the harbour, is approximately 440km2.
4.11 The site is located in the lower Waitematā Harbour, on the downtown Auckland
waterfront. The present day downtown Auckland waterfront has been formed by
shoreline reclamation and development of roading and marine infrastructure over the
past 150 years. This includes the Auckland Harbour Bridge reclamation, Westhaven
Marina, Wynyard Quarter reclamation and wharves, Viaduct Harbour reclamation and
wharves, Outer Viaduct Harbour, the Council-owned finger wharves and the Port of
Auckland wharves and terminals.
4.12 The wharves range in age from Halsey Street Extension Wharf, Western Viaduct Wharf
and the extension to Hobson Wharf (2000) to Wynyard and Princes Wharves (1920s-
1930s). Wynyard Wharf runs along the eastern side of Wynyard Point and is an open
piled concrete structure constructed during approximately the same period as the
reclamation (1920s-1930s).
4.13 The Viaduct Events Centre (VEC) on the existing Halsey Street Extension Wharf will
temporarily accommodate the Emirates Team New Zealand (ETNZ) syndicate base
(Base A). A 72m extension to Hobson Wharf will accommodate 1 double base (Base B).
4.14 The Project site lies within Freemans Bay. Seabed levels at the sites vary from -2.5m below Chart Datum (CD) at a shoal north of Halsey Street Extension Wharf to -9m CD
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mid-way along Wynyard Wharf. The Bathymetry Plan (CBD Vol A, CB45, page 2525)
shows the seabed bathymetry expressed in CD, which approximately represents the
lowest astronomical tide level. Other hydraulic features of the site include:
a) A spring and neap tidal range of 3.0m and 1.90m respectively;
b) Low tidal currents;
c) Storm surges (i.e. a weather related increase in water level) up to 0.7m;
d) Wind waves up to a significant wave height of 1.6m in the main channel;1
e) Vessel wakes up to 0.5m in height;
f) From a point taken in the centre of the Viaduct Harbour the flushing time is 50
hours for spring tides and 70 hours for neap tides. From the inner most point of
the Viaduct Harbour the flushing time is 110 hours for spring tides and 145 hours
for neap tides. It is noted that 96 hrs (4 days) is considered “good” flushing, 96
to 240 hrs (4 days to 10 days) is “fair” flushing and greater than 240 hrs (10
days) is “poor” flushing;
g) The mean sediment concentration in the harbour is about 10 g/m3 which
represents relatively non-turbid water conditions. Because many of the berth
areas have been artificially created, they are subject to sedimentation.
Sedimentation levels vary from about 30mm/year in the Viaduct Harbour to
more than 100mm/year in the deeper Wynyard port basin; and
h) Infrequent, but relatively small, tsunami.
5. INFRASTRUCTURE DESIGN
5.1 It is fair to say that the concept that was developed for the maritime and landside works
was influenced by the works of the previous America’s Cup and by the more recent
developments in Wynyard Quarter. The concept, as illustrated in Figure 2 below, was
based on:
1 United States. Environmental Protection Agency. Compliance Policy and Planning Branch. Coastal marinas assessment
handbook. s.l. : United States Environmental Protection Agency, Region IV, 1985. EPA/904/6-85/132.
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a) No reclamation;
b) Maximising the use of land based facilities;
c) Use of reinforced concrete elements for the marine based decked structures;
d) Leaving the contaminated land based material in place, capping it and creating
the infrastructure at a more elevated level, above the original ground;
e) Maximising the use of existing services; and
f) Implementing ground improvement works, where the existing perimeter
structure had low static factors of safety and/or potential for liquefaction.
Figure 2: Proposed infrastructure
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Geotechnical Conditions
5.2 Geotechnical conditions relate to ability of ground (on land) and the seabed conditions
to safely support the new structures over their design life. There was adequate historical
geotechnical site investigations and interpretation of the site conditions for the concept
design that formed the basis of the resource consent application. Since then there have
been more in depth investigations, which have by and large confirmed the outcomes of
the historical investigations.
5.3 Under the New Zealand Building Code, the syndicate based structures have been
assessed as importance level 3 (IL3 – public area structure) for 10 years (which requires that the design seismic event has a 1 in 1000 year annual recurrence interval (ARI) event) and importance level 2 (IL2 – normal structure) which requires that the design
seismic event has a 1 in 500 year ARI event, for the remainder of their design life (50
years). Reference is made in my evidence to a static factor of safety, which represents
the performance of the structure under normal operating conditions. A factor of safety is
the ratio of the restoring forces to the causal forces. A value below 1.3 is considered to
be low. A value of 1.5 is considered acceptable for new structures under normal
operating conditions. Reference is also made to liquefaction, which can occur during an
earthquake. Ground shaking causes a build-up in porewater pressures within the soil to
a level where the soil mass is mobilised. The movement of the soil is not cyclic but is
unidirectional moving under gravity, in this case, towards the coast.
5.4 Over the Wynyard Point area the rock depths are about 25m below the surface.
Reclamation materials extend over about a 7m depth of the area. As mentioned above,
the landside works will be built above present ground level by capping the existing ground
and building up from there, with minimal excavation. Their design is therefore more
reliant on pavements to support the surface loads and managing medium term
settlement. This can be achieved by adequate pavement depths and surfacing, such as
asphaltic concrete.
5.5 Previous investigations have found that the perimeter structures around Wynyard Point
have low static factors of safety and potential for liquefaction during a design seismic
event. As part of the project, it is proposed to improve the ground conditions along
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Brigham Street by installing a row of piles to both resist the liquefaction forces as well as
providing the support for the landward deck structure for the infill wharf.
5.6 Over the marine area, rock levels vary between 8 m below the seabed at Wynyard Wharf
to 5 m at Hobson Wharf. Wharf structures rely on piles for support. That support is gained
by embedding the piles into the underlying rock material. While there may be some
support from the softer overlying weaker marine sediments, the majority of the vertical
and lateral loads are taken by the underlying rock.
Landside facilities
5.7 The landside facilities are located on Wynyard Point. These are illustrated on Drawings
3233847-CA-4201 to 4207 (CBD Vol A, CB45, pages 2527-2533) and comprise:
a) New access road (1500 m2 area) with minimal earthworks;
b) Paved areas for the syndicate bases (19,000 m2 in area) with 9,000 m3 of fill
material for earthworks;
c) Paved area for access and carparking at rear of syndicate bases (1,600 m2 in
area) with 1,000 m3 of fill material for earthworks;
d) Landscaped area (2,500 m2 in area) with 1,000 m3 of fill material for earthworks;
e) Ground improvement works (about 220m linear length) and comprising a row of
piles; and
f) Services (as described in Section 6.0 of my evidence).
5.8 Although the earthworks are of a small scale there will be some adverse environmental
effects, particularly in managing the contaminated material. This aspect is discussed in
detail by Mr Phillip Ware. Monitoring and an active response strategy is important in
mitigating adverse effects. This is achieved through the enactment of a range of plans;
a remediation action plan, a construction management plan, a construction
environmental management plan, an erosion and sediment control plan and an
emergency spill response plan, all of which are recommended in the proposed conditions
of consent. This approach has been successfully used on other projects within Wynyard
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Quarter and if implemented construction related effects should be no more than minor
and acceptable.
Maritime facilities 5.9 The maritime facilities are located within Freeman’s Bay. These are illustrated on
Drawings 3233847-CA-4101 to 4111 (CBD Vol A, CB45, pages 2516-2526) and
comprise:
a) Hobson Wharf extension (approximately 7,000m2 in area) with up to 150 piles
for support.
b) Breakwaters (3,200m2 in area) with up to 120 piles for support.
c) Wynyard Wharf infill (4,000 m2 in area) with up to 80 piles for support. About
50% of the infill will be temporary, being removed at the expiry of the consents.
d) Repair and renovation to the existing Wynyard Wharf (about 4,000 m2 in area)
with the majority of this work being undertaken below the wharf deck.
e) Pontoons (up to 5,000 m2) and 150 piles for support.
f) Capital Dredging of approximately 78,000 m3 of seabed material, predominately
marine mud.
g) Services (as described in Section 6.0 of my evidence), the majority of which are
located under the wharf decks.
5.10 Construction related adverse effects relate to conflict within marine traffic and navigation
(covered in evidence of Mr Geraint Bermingham), the need for land based contractor’s
site area, noise and vibration associated with the use of large construction equipment
(covered in evidence of Mr Craig Fitzgerald), lighting (Mr John McKensey), and sediment
and erosion issue with piling and dredging (see section 7.14 to 7.16 of my evidence).
More detail on the construction process and management is addressed by Mr Kurt Grant
in his evidence.
5.11 As with the land based works, the overarching approach is to undertake monitoring and
have an active response strategy for mitigating adverse effects. This is achieved through
the enactment of a range of plans; a construction management plan, a construction
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environmental management plan, and an emergency spill response plan, all of which are
recommended in the proposed conditions of consent. This approach has been
successfully used on other marine based projects within the lower Waitematā Harbour.
5.12 Some of the dredged material will be converted into mudcrete and placed to form
underwater bunds. Mudcrete is made by mixing the dredged mud with cement and can
be used as reclamation fill and for bund walls instead of using rock. The cement used in
stabilising dredged material also assists in “locking in” some contaminants and reduces
leaching out into the surrounding environment. When the mudcrete sets, it solidifies to a
Waitemata Sandstone-like material with strengths ranging from 200kPa to 2000kPa.
Other attributes is that it cures within 1-2 days, can be placed in all weather conditions
and under water and, as it is hydroscopic, seawater is drawn into the mudcrete mixture,
not allowing sediment plumes to be released.
5.13 The longer term related adverse effects relate to coastal processes (basin flushing,
wave/wake reflection, sedimentation) and managing coastal hazards. These are
discussed in Section 7.0 of my evidence.
6. STORMWATER AND SERVICES
6.1 Services plans are illustrated on Drawings 3233847-CA-4401 to 4407 and 4451 to 4457
(CBD Vol A, CB45, pages 2534-2547).
Stormwater
6.2 For the land based facilities it is proposed to install a new primary stormwater system
(comprising catchpits, slot drains and pipe networks) to collect storm flows up to the 10
year ARI event), overland flow paths (for storm flows up to the 100 year ARI event) and
stormwater treatment for all new works containing impermeable surfaces. Stormwater
treatment will use proprietary treatment cartridges, housed underground within a vault
due to the lack of space within the Project. There is the opportunity, however, for the new
access road and for the access and carpark area at the rear of the syndicates to use rain
gardens for stormwater treatment. Stormwater treatment devices will remove 75% of
suspended sediment discharges, in accordance with the Auckland Unitary Plan
requirements.
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6.3 For the marine based facilities it is proposed to install a new primary stormwater system
(comprising slot drains and pipe networks) to collect storm flows up to the 10 year ARI
event), overland flow paths (for storm flows up to the 100 year ARI event) and stormwater
treatment for all new works containing impermeable surfaces. These works include the
Hobson Wharf extension and the area on the VEC housing ETNZ. Stormwater treatment
will use proprietary treatment cartridges, housed below the wharf deck within a vault.
Flows in excess of the stormwater treatment flow will discharge directly to the CMA.
Stormwater treatment devices will remove 75% of suspended sediment discharges, in
accordance with the Auckland Unitary Plan requirements.
6.4 In addition to providing a positive stormwater collection and treatment system, there is
no potential for flooding of, or damage or nuisance to, other properties. The shoreline is
protected by seawalls and the wharf discharges are at a distance from the shoreline
which minimises any potential for scour and erosion from the discharges.
6.5 ITA and HS will also need to be managed for boat repair at the syndicate bases (ITA)
and limited quantities of Class 3 Flammable substances (HS) at the syndicate bases.
Potential discharges from the sites will be managed through ITA Environmental and
Hazardous Substances Management Plans (ITA EHSMPs). Potential ITA and HS Risks
will be managed using the ITA Environmental and Hazardous Substances Management
Plans and Emergency Spill Response Plans (ESRPs).
6.6 In my opinion any potential adverse effects of stormwater and ITA discharge via
stormwater in terms of land use, discharge quantity and quality, and of HS use, storage
and disposal are considered to be less than minor based on the site features and
provided the measures described above are implemented through consent conditions.
(conditions 136 to 168).
6.7 The proposed landside facilities have minor beneficial effects compared to the existing,
as there is a reduction in potential for sediment discharge. This is due to the proposed
modern stormwater treatment, car park removal and a reduction in the storage of
hazardous substances with the removal of the Stolthaven South and BST tank farms.
6.8 Similarly, the maritime facilities have minor beneficial effects compared to the existing
facilities as the discharges from part of the VEC will have stormwater treated discharges
(i.e. there is currently no stormwater treatment).
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Other Services 6.9 Services include water supply, wastewater, power, and communications. Based on
available information from service providers, existing adjacent services have sufficient
capacity for the Project. In some cases, some minor upgrading works are required; for
example, for power supply additional transformer capacity will be introduced. Letters of support from the Service Providers are attached as Appendix A to my statement of
evidence. This correspondence confirms sufficient capacity in either their supply or
acceptance of the service connection.
6.10 Services on land will be in underground trenches. Services on the CMA will be routed in
underwharf galleries.
6.11 For the proposed services, any adverse effects are considered to be less than minor on
the basis that the recommended measures (including planning and coordination of
works, temporary traffic management and methods such combined trenches, directional
drilling and routing of works) are implemented through consent conditions (conditions 23
to 45).
7. COASTAL PROCESSES
Governing factors in the overall layout
7.1 Project criteria for moored boat tranquillity were established from internationally
recognised performance criteria. Residual wakes are more critical than residual wind
waves in the berthing areas, with the objective of significant wake heights being less than
0.1m (with an associated wake period of 5 s).
7.2 A range of layouts with differing wharf and berthing areas, and layouts of wave panels
were considered as part of the overall assessment. As a general conclusion, to achieve
the objective of minimising the adverse effects on tidal flushing there should be the least
obstruction to flow (i.e. minimising the number of breakwaters and wave panels).
Conversely to achieve the objective of minimising the effects of waves and wakes on
berth tranquillity there needs to be significant breakwaters and wave panels installed,
bearing in mind navigational constraints such as having an adequate entrance. These
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two objectives are therefore mutually exclusive. As there is no optimal solution that
achieves both some form of compromise layout was required.
7.3 From the tidal modelling, it is clear that the tidal flows moving through the Outer Viaduct
Harbour encourage eddy formations that develop counter eddy flow into the Inner
Viaduct Harbour, particularly for the flood tide. These eddies encourage good flushing of
the basin. For berth tranquillity within the Outer Viaduct Harbour, however, there is a
need to prevent the ferry wakes from the Queens/Princes Basin entering under Hobson
Wharf by installing wave panels. This in turn inhibits the tidal flow through the Outer
Viaduct Harbour which increases the flushing periods for the entire Viaduct Harbour
7.4 On balance it was considered that it was more important to achieve the tranquillity criteria
(wake heights < 0.1m) in the berth areas, resulting in the preferred option having wave
panels under Hobson Wharf and breakwaters on the seaward edge of the Wynyard
Wharf south waterspace. Failure to meet the tranquillity criteria would render the Project
ineffective for hosting the America’s Cup event. This does result, however, in an increase
in flushing times. The layout of the marine works and the wave panels/breakwaters are
shown in Drawing 3233847-CA-4109 (CBD Vol A, CB45, page 2524).
Tidal Flows and currents
7.5 Tidal currents are low (<0.1 m/s) in the Wynyard Wharf south waterspace and the Viaduct
harbour. Tidal currents will be altered by the proposed layout, but the resulting velocities
remain low.
7.6 The effects of the proposed development on tidal flows and currents are considered to
be no more than minor because of the localised extent (i.e. confined to the basins) and
limited actual scale of these changes.
Tidal Flushing
7.7 Modelling of the harbour basins enabled the changes in flushing times to be assessed.
The flushing times were defined as the time taken for 37% (i.e. 1/e where e is equal to
2.72) of the flow to be exchanged in any area. The model output locations are shown on
Figure 3, with the flushing results listed in Tables 1.
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Figure 3: Model output locations
Table 1: e-folding times of harbour basin flushing pre and post development – spring tide
Location e- folding Time (hrs) - e- folding Time (hrs)
Neap Tide (typical 1.9m range) Spring Tide (typical 3m range)
Existing Post-development
% Change Existing Post-development
% Change
7 8 33.2 +315 6.5 18.5 +185 8 12 32.2 +168 13.5 17.5 +30 9 38.8 99.5 +156 38.5 50.5 +31 10 21.7 43.2 +99 27.7 18.5 -33 11 64.3 113.8 +77 50.0 63.0 +5 12 64.5 101.0 +57 47.3 51.0 +8 13 125.8 175.7 +40 100.7 112.8 +12 14 145.2 199.0 +37 116.7 128.5 +10
7.8 For the Wynyard Wharf South Waterspace the Project reduces the entrance width and
increases the basin volume by around 8% due to dredging. Basin flushing time remains
in the “good” category. For the Outer Viaduct Harbour, the effective exchange area is
reduced due to construction of wave panels beneath Hobson Wharf (although having
some porosity) and modification of the Wynyard Wharf South Waterspace and increases
in the basin volume by some 11% by dredging. Basin flushing time remains in the “good”
category.
7.9 For the Inner Viaduct Harbour, there are no changes to entrance width or volume.
Changes to the Outer Harbour and the Wynyard Wharf South Water-space, however,
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affect the tidal velocities and the flushing. The water exchange retains a ‘good’ to ‘fair’
category, although may reduce from ‘good’ to ‘fair’ in the mid-parts of the inner harbour
during neap tides. All the locations are predicted to remain within or better than the “fair”
240 hour band.
7.10 Stormwater discharges at the Daldy St outfall (near North Wharf) remain in Freemans
Bay and are transported into the Viaduct Harbour rather than being flushed offshore into
the main Waitemata Harbour channel as currently occurs. These discharges are slowly
reduced as water exchanges with each tide. Actual stormwater effects within the harbour
are likely to be affected by the time of stormwater discharge during the tidal cycle and
preceding rainfall conditions influencing the pollutants that are discharged.
7.11 Flushing is only one parameter affecting water quality. Measures such as management
and treatment of stormwater discharges, and removal of jetsam and flotsam are also
important in determining water quality within a basin and could be addressed via a
management plan. In his evidence, Mr Paul Kennedy, discusses the effect of tidal
flushing on water quality in relation to the discharge of stormwater, algal growth and
overall ecology as well as implementing an Inner Viaduct Harbour Environmental
Management Plan through conditions of consent (Conditions 117 to 119).
Waves and Wakes
7.12 Although the focus of the wave/wake modelling was based on locating the wave panels
and breakwaters to meet the tranquillity criteria, considerable effort went into
understanding the extent of any reflected wave/wake climate.
7.13 Most of the breakwaters have a two rows of wave panels, with the seaward high porosity
panel minimising the amount of wave reflection and the leeward solid panel minimising
wave transmission. Overall, the assessment concluded that the reflected wave/wake
climate would be better than the existing situation, including the Maritime Museum basin.
Dredging
7.14 The 36th America’s Cup vessels will have a draft of 5m and therefore require a water
depth of 5.5m CD. To achieve this some 78,000 m3 requires dredging with the Wynyard
Wharf South Waterspace and outer Viaduct Harbour. There is also the potential to yield
a further 9,000 m3 of seabed materials from the drilling operation, if cored piles are used.
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See Drawing 3233847-CA-4108 (CBD Vol A, CB45, page 2523) for the location and
depth of required dredging.
7.15 Disposal options for this dredging include re-use of the material as fill material (for
example on the Wynyard Point site), transport to a consented landfill, dumping at an
approved ocean disposal site, or mudcreting for use as fill in an approved reclamation. .
7.16 The dredging operation will create sediment plumes which become more diffuse away
from the dredger. Near field modelling of the dredge plume and previous dredging
campaigns have both shown adverse effects from dredging plumes to be less than minor
with localised (less than 200m from the dredger) and temporary increases in suspended
sediment. The depth of material deposited at any single location from the plume is
expected to be undetectable.
7.17 A monitoring plan for dredging and placement of mudcrete in the CMA is required in the
conditions of consent (conditions 51 to 69). Such a plan is based on previous dredging
campaigns and is comprehensive.
Sedimentation
7.18 Existing and historical sedimentation provides a practical guide to future sedimentation
rates in Viaduct Harbour and Wynyard Wharf South water-space. In particular, previous
development of the Outer Viaduct Harbour in the late 1990s allows direct comparison of
pre- and post- development sedimentation rates. This approach is also consistent with
the methodology followed for the past 25 years for estimating sedimentation rates within
the lower Waitematā Harbour.
7.19 Sedimentation will increase in the more tranquil basins/harbours, at a similar scale to
existing sedimentation rates. Potential adverse effects are therefore expected to be
minor and to be managed using existing maintenance dredging practices in a similar
manner to present sedimentation. Any maintenance dredging will be carried out under
the existing consents.
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Coastal Hazards and Climate Change Adaptation
Sea Level Rise (SLR)
7.20 For functionality, the proposed Hobson extension and wharf infill sections at Wynyard
Wharf are operationally required to have the same level as existing wharves.
7.21 Adaptation to SLR (and therefore coastal hazards) for the wharf structures will be based
on the best practicable solution taking into account whole of life costs, the tenure and
renewal of structures and their functional use. At this stage, it is proposed that the piles
of a structure will be designed to include for a SLR of 1m, with the deck and wave panels
being upgraded when the structures are adapted.
7.22 Within the land area adjacent to Brigham Street, consideration will need to be given to
the necessity for adaptations to coastal hazards in the future. This would best be
addressed with the future change in land use (to park land) and with any adjacent
development. This is unlikely to be required within the proposed 10 year consent period
for the temporary works and base buildings.
Storm Surge and Wave Overtopping
7.23 As the proposed wharf deck level (5.3mCD) matches the existing deck levels, the storm
tide and overtopping relationships for the proposed wharves are the same as for the
present situation. For a northerly 50 year ARI wave, mean high water springs, a 50 year
ARI storm tide and future sea level rise to 2050 were considered. These indicate that
overtopping would be generally acceptable up to 2050. At about this time, raising the
wharf deck level will need to be investigated.
Erosion
7.24 Seawall armouring of the city waterfront provides erosion protection. This project will not
cause erosion of adjacent areas.
Tsunami
7.25 From studies to date it appears that the tsunami hazard relates to regional and distant
sources, which provides a window of between approximately 1 hr (regional source) and
12 hours (distant source) to evacuate the structures (NIWA, 2009; NIWA, 2010; GNS,
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2013). An emergency evacuation plan is provided for in the proposed conditions of
consent (conditions 174 to 175) and such a plan has already been prepared and
generally agreed with Civil Defence.
8. CHANGES IN THE CONCEPT DESIGN SINCE LODGEMENT
8.1 Since lodgement there has been some changes in the concept design as a result of
optioneering and detailed design. These changes are described below and some illustrated in Appendix B of my evidence.
8.2 The dredging for the navigation channel is slightly wider at the northern end. This is
shown in Figure B1 attached to my evidence in Appendix B. The area covered by the
channel was 1.08 ha, but is now 1.24 ha. The quantity be dredged in this channel,
however, has been reduced from 30,000 m3 to 20,000 m3. This change is negligible in
terms of the effects of dredging.
8.3 It was decided that in the superyacht berths to dredge to a level of -4.5m CD rather than
-5.5m CD. Overall this reduces the dredged material (including pile workings) from
87,000 m3 to 73,000 m3.
8.4 ETNZ has advised that some syndicates may use detergents in their wash-down water.
This was discussed with Auckland Council and it was agreed to include a condition of
consent (condition 141) to enable details as to the use of detergents as part of the
Industrial and Trade Activities Hazardous Substances and Environmental Management
Plan. The wash-down water would be isolated from discharging through the stormwater
system.
8.5 In order to finalise the water supply demand to the syndicate bases and to avoid fire
rating the building walls, it was decided to have a separate structure for hazardous
goods. This would be a low level structure located in the base yard and similar to the one
shown in Figure B2 at Appendix B. I understand that the latest version of the Design
Requirements allow for such a structure.
8.6 Detailed geotechnical investigations have revealed that the extent of liquefiable soils is
less extensive than originally thought. Ground improvement works will therefore not be
as extensive and will primarily aim to retain the surface soils and support the wharf
structure. These works will also improve the static factor of safety for the landside area.
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9. COMMENTS ON THE AUCKLAND COUNCIL REPORT
9.1 I have read the Council report. In general I agree with the conclusions reached in the
reports of Mr Sam Morgan (coastal processes) (CBD Vol D, CB138, page 3627), Mr
Charlie Brightman (geotechnical) (CBD Vol D, CB139, page 3642), Ms Gemma Chuah
and Ms Hillary Johnston (stormwater and ITAs) (CBD Vol D, CB142, page 3698), and Mr
Ahad Khan (development engineering) (CBD Vol D, CB147, page 3797).
9.2 I have met with the above report authors and together we have prepared the JWS. The
main outcome of the JWS was to agree the intent of the wording in the related conditions
of consent. These agreed conditions now form part of the Applicant’s Proposed
Conditions of Consent (attached to the evidence of Karl Cook and Vijay Lala as
Attachment A).
10. COMMENTS ON SUBMISSIONS
10.1 Mr Richard Gladwell of Sail World New Zealand Ltd (Submission #51) made a
comprehensive submission. One of the points he made was “5. Despite the presence of
two break waters in the waterspace between Halsey Street Wharf and Wynyard Point,
these are unlikely to provide the calm water required for Cup teams and superyachts.
The area does have whitecaps in reasonably strong winds and to provide the required
shelter the sea walls need to be extended, or some other wave break used.” I have
discussed this point with Mr Gladwell and he has advised that he will not be presenting
evidence on it. From a practical perspective, the breakwater locations and extent are
constrained by navigational requirements related to clearances for vessels berthing at
Wynyard North and the width of opening between the breakwaters. Nevertheless, the
tranquillity criteria as discussed in para 7.1 of my evidence are generally met within this
waterspace.
10.2 The submissions from mana whenua in opposition to the project make the point that the
Waitemata Harbour has degraded over time due to extensive reclamations and port
development.
10.3 Cumulative historical developments within downtown Auckland have involved significant
reclamation. It is acknowledged that many of the natural coastal features from pre-
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European times have been lost through that reclamation. Such features would have
included small beaches, headlands, reefs, and cliff-lined embayments.
10.4 It is noted that this Project does not include reclamation but there are wharf extensions
into the harbour. Cumulative effects relates to the capability of a natural system to
withstand changes. This can sometimes be addressed by assessing whether any
thresholds have been exceeded which could allow that natural system to degrade to a
significant degree. An example of such an assessment is the flushing periods within the
inner Viaduct harbour, which is, discussed in paras 7.7 to 7.11 of my evidence. I
concluded that the flushing periods generally remain in their “good” or “fair” category but
none change into the “poor” category.
10.5 Historical reclamations and extensions into the harbour have become part of the existing
environment for which this Project has generally been assessed against.
11. CONCLUSION
11.1 Based on implementation of the Conditions of Consent and my experience with other
coastal processes studies, and with other port, maritime and dredging projects, I have
formed the following conclusions;
a) Adverse effects associated with landside works will be minor;
b) Adverse effects associated with maritime works will be minor;
c) Services can be adequately provided for the project and this has been endorsed
by the service providers;
d) Adverse effects associated with coastal processes will generally be minor;
e) The Project design has considered natural hazards such as sea level rise, storm
surge and tsunami. Management processes implemented through either design
or management plans have allowed for these hazards for at least the next 100
years;
f) Beneficial effects are associated with creating more tranquil berthing areas for
vessels; and
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g) Beneficial effects are associated with treatment of stormwater of existing areas
which are untreated at present.
Stephen John Priestley
7 August 2018
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