before the waikato regional council app139219 rma · 2019. 12. 1. · focussing on surfing reef...
TRANSCRIPT
Before the Waikato Regional Council
App139219
Under the Resource Management Act 1991 (RMA)
In the matter Application for a new coastal permit to operate a spat farm
in Whauwhau, Whitianga.
Applicant Ohinau Aquaculture Limited
Statement of Evidence of Shaw Trevor Mead
Date: 1 December 2019
1. INTRODUCTION
1.1. My full name is Shaw Trevor Mead and I am an environmental scientist
based at Raglan. I am currently an Environmental Scientist and
Managing Director at eCoast, which is a marine consulting and research
organisation.
2. QUALIFICATIONS AND EXPERIENCE
2.1. I hold BSc (School of Biological Sciences) and MSc (Hons) (School of
Environmental and Marine Sciences) degrees from the University of
Auckland, and a PhD degree from the University of Waikato (Earth
Sciences).
2.2. I have over 25 years’ experience in marine research and consulting, have
authored/co-authored 60 peer-reviewed scientific papers and 2 chapters in
a practitioner’s textbook on beach management1 and coastal protection2,
and have solely or jointly produced over 450 technical reports pertaining
to coastal oceanography, coastal engineering (design and impact
assessments), marine ecology and aquaculture. I have undertaken over
two thousand research and consulting SCUBA dives around the coast of
New Zealand and overseas, and have led many comprehensive field
investigations that have addressed metocean, biological and chemical
components of the coastal environment. I am also a part-time lecturer
(environmental change and coastal engineering) and research provider at
Unitec. I am a member of the New Zealand Coastal Society (ENZ), the
New Zealand Association of Impact Assessment, and am on the editorial
board of the Journal of Coastal Conservation, Planning and Management.
In addition, I am a technical advisor for the Surfbreak Protection Society
(NZ) and Save the Waves Coalition, which mostly entails consideration
of marine structures and developments and the impacts they will have or
1 Mead S. T., 2017. Chapter 6 - Beach Management. In: Marine and Coastal Resource
Management: Principles and Practise. Eds D. Green and J. Payne. Routledge, 328 pg.
2 Mead S. T., and J. C. Borrero, 2017. Chapter 16 -Surf Science and Multi-Purpose Reefs.
In: Marine and Coastal Resource Management: Principles and Practise. Eds D. Green and
J. Payne. Routledge, 328 pg.
have had on surfing breaks; I am co-author of the New Zealand
Management Guidelines for Surfing Resources3, which were first released in beta
version in October 2018 and finalised in September 2019
(https://surfbreakresearch.org/downloads/).
2.3. I have a background in coastal oceanography, numerical modelling,
marine ecology and aquaculture. I studied for my MSc degree at the
University of Auckland’s Leigh Marine Laboratory, undertaking subtidal
research there from 1994 to 1996 directed at the fertilisation success of
sea urchins as a basis for the sustainable management and development of
the commercial market. My MSc in Environmental Science, Marine
Ecology and Aquaculture included 4th year Environmental Law and a
dissertation on the Quota Management System (QMS) legislative review.
My PhD was primarily in coastal oceanography, with the marine
ecological components of my Doctorate directed towards subtidal habitat
enhancement of marine structures. The physical oceanography
component was focussed on understanding the effects of coastal
bathymetry on surfing wave breaking characteristics using field
measurements (bathymetry surveys, aerial photography and GPS
positioning of in situ data collection) and hydrodynamic numerical
modelling. My PhD thesis is comprised of 6 peer-reviewed Journal
Papers that describe the meso-scale components that combine to create
high-quality surfing breaks and empirical methods of determining wave
breaking intensity of high-quality surfing waves. My professional career
has included involvement in a wide range of coastal consulting and
research projects that have included the design of coastal structures and
developments, and assessments and monitoring of physical and ecological
effects of marine construction, MPR design and surf break impact
assessment, coastal erosion control, marine reserves, dredging, outfalls,
oil industry, aquaculture ventures and various other coastal and estuarine
projects that have included hydrodynamic (waves and currents), sediment
transport and dispersion modelling (including contaminants, suspended
sediments, freshwater, hypersaline water, nutrients and petro-chemicals).
3 Atkin, E., Bryan, K., Hume, T., Mead, S. T., and Waiti, J., 2019. Management Guidelines
for Surfing Resources. Raglan, Aotearoa New Zealand: Aotearoa New Zealand Association
for Surfing Research. ISBN: 978-0-473-49540-4
2.4. Further to this, with direct relevance to the present case in terms of surf
break impacts, is that the focus of my PhD and subsequent consulting and
research work has been on wave/structure interactions and the impacts of
seabed morphology and coastal structures on waves, currents and
sediment transport. For instance, during my PhD I interpreted the
morphologies of 44 bathymetries from high quality surfing breaks around
the world to consider how different components of the morphology
impacted on wave transmission. I have produced several peer-reviewed
scientific papers on the effects of wave-seabed interactions on surfing
breaks, including how offshore wave focussing (which is relevant to the
current proposal) can influence surfing breaks on scales from the inner
continental shelf to sub-tidal reefs (Mead et al., 20034). More recently I
have investigated natural offshore focussing features (ebb-tidal deltas,
offshore reefs and ridges, etc.) and analysed the morphology (shape and
volume) and locations (distance offshore) of these features (Atkin, Mead
and Phillips, 20195).
2.5. I have been involved with the assessment of the impacts of aquaculture
(both physical and ecological) and identification of aquaculture
management areas (AMA’s) for over 20 years. These projects have
included mussel and salmon farming in the Marlborough Sounds, oyster
farming in Whangarei Harbour and Matarangi Estuary, AMA’s for the
Northland Region and mussel farming in the Firth of Thames, Bay of
Plenty and Pegasus Bay.
3. CODE OF CONDUCT
3.1. I have read the Code of Conduct for Expert Witnesses set out in the
Environment Court's Practice Note 2014. I have complied with the Code
of Conduct in preparing my evidence and will continue to comply with it
while giving oral evidence before the Environment Court. My
4 Mead, S. T., K. P. Black, J. Frazerhurst and B. Scarfe, 2003. The Effects of Wave
Focussing on Surfing Reef Site Selection, Surfing Wave Quality and ASR Design at Scales
of Inner Continental Shelf to Sub-Tidal Reef. 3rd International Artificial Surfing Reef
Symposium, Raglan, New Zealand 23-25 June 2003. ISBN 0-473-09801-6 2003 5 Atkin, E.A.; Mead, S.T., and Phillips, D., 2019. Investigations of offshore wave
preconditioning. In: Bryan, K.R. and Atkin, E.A. (eds.), Surf Break Management in
Aotearoa New Zealand. Journal of Coastal Research, Special Issue No. 87, pp. 78–90.
Coconut Creek (Florida), ISSN 0749-0208.
qualifications as an expert are set out above. I confirm that the issues
addressed in this statement of evidence are within my area of expertise,
and I have not omitted to consider material facts known to me that might
alter or detract from my expressed opinions.
4. EXECUTIVE SUMMARY
4.1. The officers report and initial expert reviews indicated a number of
deficiencies in the application and AEE. These were to be addressed at
the hearing, which would have continued to provide some uncertainty
with respect to addressing the issues identified by our review (as well as
other reviewers and submitters). However, the new expert evidence
received in the past week includes further information to address the
issues identified in our review (Appendix 1), as well as many others
outside of my scope and areas of expertise. Even so, there are several
areas of concern with respect to potential impacts that in my opinion,
remain unresolved.
4.2. It is my opinion that the impacts on coastal processes (i.e. sediment
transport) and the 3 or more surf breaks in the lee of the three 10 Ha spat
collection blocks have been very poorly addressed and a large amount of
uncertainty remains, since there is no site-specific data and little to no
existing literature pertaining to the hydrodynamic impacts of marine
farms on waves; although several previous investigations have been
undertaken with respect to effects on currents. Dropper ropes along the
backbones will have similar impacts as have been investigated for mussel
farms; redirecting currents and dampening short period waves (the latter
of which are dominant on the north eastern coast of New Zealand).
However, the significance of these impacts has not been addressed by the
applicant, since it cannot be addressed without site-specific data
collection. This makes it difficult to determine what they may be and the
magnitude of them. It is important to note that swell corridor mapping is
not directly for the assessment of impacts to surf breaks, it is to indicate
whether or not there is the potential to impact on a surf break, and if so, as
in the present case, flags requirements to assess the potential impacts.
4.3. In my opinion (and Dr Bell’s), the original ecological assessment was very
sparse with respect to data/sampling locations, did not provide a good
description of the benthic communities or evaluate its biodiversity, and so
cannot be considered adequate as a baseline survey; for example, a single
blurry frame-grab from the underwater video was provided for 30 ha of
benthos. In addition, in order to measure effects at a potential impact site
(i.e. the benthic ecology under the spat collection blocks), time-series data
of the potential impact site has to be compared against control data, that is
from a site with similar physical and biological properties that is outside
the zone of potential impact. A standard BACI (Before/After,
Control/Impact) monitoring approach is required. The existing
information presented in the AEE is insufficient for impact monitoring,
and at best will only detect change that will not be able to be attributed to
the activity and so will likely be written off as ‘natural variation’.
4.4. It is unclear how, and in my opinion not possible, that monitoring of
organic enrichment of sediment can be used as a proxy to impacts on
benthic ecology. The proposed monitoring suggests that “If any
ecologically significant effects are measured, a suitability qualified and
experienced expert will advise what additional monitoring or mitigation
methods are required, if any, and the timeframes for undertaking that
monitoring or mitigation”. Similar to determining ecological impacts by
measuring organic enrichment, it is not possible to go back in time and
collect monitoring data once you detect an impact, this is why robust and
useful monitoring should follow a procedure that can detect impacts at the
site in question (i.e. a BACI monitoring design).
5. SCOPE OF EVIDENCE
5.1. My involvement in this case has been since early October 2019, when my
consultancy was asked to provide a review of the application and
associated information for the proposed spat farm in terms of coastal
processes/surf break impacts and marine ecology. The review is attached
here as Appendix 1, while the body of my evidence summarises these
findings and comments on the recently received evidence from Dr
Beamsley, Dr Wilson and Ms Britton.
6. NEW INFORMATOIN
6.1. From our review of the information submitted for this resource consent
application (Appendix 1), it is my opinion that the quality of the original
application is very low and has a deficit of information relevant to
determining the potential effects on the environment (e.g. no collection of
hydrodynamic (waves, currents, tides) data, little biological data sampling
and paucity of analysis, etc.). Many of these deficiencies have been
identified in the officers report and reviews by experts, and consequently
discussed in additional expert evidence received early in the past week.
However, although some areas have been addressed (e.g. concerns with
biosecurity), in other areas (e.g. coastal processes, surf break impacts,
ecological monitoring) the additional evidence/information is baseless
and is either not relevant to the site or made in a complete absence of
actual data. Due to many deficiencies in the original application, the
piecemeal approach to address these deficiencies has made the application
difficult to evaluate, likely for both submitters and experts.
6.2. As stated above, the details and background information leading to my
initial conclusions with respect to the application and potential
environmental impacts are provided in Appendix 1 and are not discussed
in detail in the body of this evidence. My main point of concern as
outlined in the summary above are addressed in the following Sections
with reference to the appropriate expert’s evidence.
6.3. It is my opinion that the impacts on coastal processes (i.e. sediment
transport) and the 3 or more surf breaks in the lee of the three 10 Ha spat
collection blocks have been very poorly addressed and a large amount of
uncertainty remains, since there is no site-specific data and little to no
existing literature pertaining to the hydrodynamic impacts of marine
farms on waves; several investigations have been undertaken with respect
to effects on currents. Dropper ropes along the backbones (x11 at 20 m
intervals) in each block will extend to ~15 m, or approximately ~75% of
the water column. These will have similar impacts as have been
investigated for mussel farms; redirecting currents and dampening short
period waves (the latter of which are dominant on the north eastern coast
of New Zealand). However, the significance of these impacts has not been
addressed by the applicant, since it cannot be addressed without site-
specific data collection. This makes it difficult to determine what they may
be and the magnitude of them. It is important to note that swell corridor
mapping is not for the assessment of impacts to surf breaks, it is to
indicate whether or not there is the potential to impact on a surf break, and
if so as in the present case, flags requirements to assess the potential
impacts.
6.4. It remains unclear how potential impacts to marine mammals will be
mitigated by ‘tightening’ the drop-lines. It is known that marine mammals
have become entangled in ropes in New Zealand associated with fishing
and aquaculture practices. It is now proposed that this risk will be
mitigated by ensuring the spat-ropes will be kept tight by weighting the
drop-lines, although it is unclear how this will alleviate this threat.
6.5. Uncertainty with respect to the efficacy of the selected site as a spat-
collection area. There are conflicting views by local submitters as to
whether mussel spat settlement occurs in large and regular numbers at the
site. Pilot studies would provide some direction with this respect. Should
the activity go ahead, conditions that ensure that the buoys, back-bones
and anchors be removed in the event of low spat recruitment, should be
included in the consent. There is similar uncertainty with respect to the
design of the mooring system. Without in situ wave measurements to
calibrate a numerical transformation model, it is not clear how the system
will be designed and specified.
7. EVIDENCE OF DR BEAMSLEY
7.1. It is my expert opinion that many of the statements made by Dr Beamsley
with regard to impacts on hydrodynamics (currents and waves), and
consequently coastal processes and surf breaks are lacking in any form of
site-specific data to support them. Of note, Dr Beamsley’s evidence, as
well as the relevant studies he has been involved with that are listed in his
evidence, do not in any case include actual measurements of wave-farm
interactions and/or any quantified information pertaining to the known
attenuation that marine farms have on wave transmission.
7.2. With respect to potential effects on surf breaks, Dr Beamsley indicates the
uncertainty with respect to the existence of surf breaks long this stretch of
the coast. Unfortunately, as described in the initial review (Appendix 1),
this coast has been identified as a Known Surfing Coastline (KSC)6 as
part of the identification and swell corridor mapping of regionally
significant surf breaks in the Waikato Region7, although this information
was not identified by Dr Beamsley (or Ms Gibberd in the initial review).
It is unknown whether the information available on the surf breaks
(KSC’s, in this case Devils Point to Tohetea Stream) would have been
provided had Dr Beamsley followed the Guidelines during the assessment
he undertook; i.e., Step 1 of Section 3. Guidelines for Resource Users and
Consent Applicants of the Management Guidelines for Surfing Resources
states “Check with consenting authority for existing resources relevant to
surf break management.”.
7.3. Even so, the Surfbreak Protection Society’s submission identified that the
coast in the lee of the proposed marine farms includes at least 3 surf
breaks, and Dr Beamsley indicated that there was potential that surfing
occurred in this area that are within their swell corridors, and so required
assessment. However, it is unclear how this assessment was undertaken,
since very little information pertaining to it is presented. It is important to
note that swell corridor mapping/identification is not directly for the
assessment of impacts to surf breaks, it is to indicate whether or not there
is the potential to impact on a surf break, and if so as in the present case,
flags requirements to assess the potential impacts. The Guidelines include
extensive stepwise descriptions of the process “to provide instruction on
surf break characterisation and impact assessment to those who wish to
undertake resource use and development activities within the CMA,
inland waterways, catchment and coastal hinterland that may impact on a
surf break(s).”. However, apart from an evaluation of the wave climate
(which omits the importance of SE groundswell with respect to surfing at
these sites) and swell corridor and discussion of the potential impacts of
the structures with respect to wave attenuation, Dr Beamsley’s assessment
of effects on the KSC breaks in the lee of the proposed marine farms does
not consider the majority of factors that need to be addressed, which
6 Atkin, E.A., 2017. Known surfing coastlines in the Waikato region. Raglan, New
Zealand: eCoast Marine Consulting and Research. Letter Report, Waikato Regional
Council.
7 Atkin, E. A. and Mead, S.T., 2017. Surf Breaks of Regional Significance in the Waikato
Region. eCoast Technical Report Prepared for Waikato Regional Council.
makes it difficult to understand how Dr Beamley determined through the
application of the Guidelines that the risk was ‘low’. For example,
characterisation of the surf breaks is not reported, and from Dr
Beamsley’s evidence it seems very unlikely that the primary important
step of stakeholder engagement (including, but not limited to, local Iwi,
surfers, resource managers, local businesses, etc.) to collect data on the
attribute values of surfing resources was not undertaken.
7.4. It should also be noted that Dr Beamsley’s interpretation of a locally
significant surf break is not consistent with published information (Atkin
et al., 2019; Orchard et al., 2019) 8, and the statement that locally
significant surf breaks are “reliant of specific, often rare, conditions to
break, and are therefore likely to be rarely surfed” is not consistent with
this.
7.5. The methodology presented in the guidelines has its foundations in an
understanding of the resources being assessed; in particular the surf break
type (Atkin et al., 2019; Mead, 2000; Scarfe, 2008) which provides a
sensitivity rating; which informs the Likelihood of impact. There is no
evidence of the sensitivity assessment, and no information to support a
sensitivity assessment. Dr Beamlsey indicates that a surf break in the KSC
could be a point break (3); the most appropriated consequent category is
significant9 (3); a liberal likelihood of impact is Moderate (C)10, and more
a more conservative view is Likely (B)11. For ether likelihood of impact,
the risk rating for the activity has the potential to be high rather than low.
7.6. As above, it is unclear how Dr Beamsley undertook a risk assessment in
the absence of a variety of information required to make such an
assessment. In addition, it is my opinion that aspects put forward to
discount potential effects are not relevant to this case, such as the work of
8 “Secret Spots” are perceived as being known to a few, closely guarded and/or challenging
to access (Atkin et al., 2019; Orchard et al., 2019)
9 Activity temporally effects, for sustained periods of time, access to and/or enjoyment of a
surfing resource; and/or activity results in health and safety issues. No physical impacts
10 Potential for activity to occur, activity being undertaken near to SBA or within
catchment; and/or examples exist; and/or sensitivity rating: 2-3
11 Potential for activity to occur frequently, activity being undertaken in or near to SBA;
and/or similar examples exist; and/or sensitivity rating: 3-4
Plew et al. (2005)12 and the impacts of the wreck of the RV Rena on wave
propagation. The effects on waves due to the wreckage of the MV Rena
is in no way comparable to the potential effects of the 3x 10 ha spat farms
at Whauwhau Bay, the former (MV Rena) impacts through changes to
refraction and diffraction patterns, while the latter (the proposed marine
farm) impacts through wave attenuation/height decrease.
7.7. As noted by Dr Beamsley, there is very little information available to
assess the wave attenuating impacts of the proposed marine farm; the
work of Plew et al. (2005), can not be applied to the current application
due to a number of factors, including the very small wave heights and
periods assessed, the size and density of the marine farms investigated,
and the lack of consideration of how these changes relate to the coastline
in the lee of the structures. Even so, Dr Beamsley considers that the
roughness of the dropper-lines and the distance offshore will result in
local minor and no distance impacts on wave climate and hydrodynamics
“Given the less than minor impact of the proposed spat farm on both the
incident wave climate (paragraphs 31-34) and hydrodynamics
(paragraphs 35-38), my expert opinion is that there will be a less than
minor impact on the natural state of the existing environment at the farm
site with respect to waves and hydrodynamics, and no impact at any
distance from the site”. In my opinion, the magnitude of the impacts are
not a ‘given’ based on the lack of information and data relevant to the
proposal for the assessment of impacts on the surf breaks and coast in the
lee of the proposed farms.
7.8. I disagree with Dr Beamley’s statements that the ‘roughness’ of the
proposed marine farms due to the size of the dropper lines and mussel
stocking density will be “several orders of magnitude” less than those on
a mussel on-growing structure; this statement is saying that dropper lines
with mussels attached at on-growing farms have thousand to tens of
thousands of times more ‘structure’ in the water column, which is simply
incorrect. It is noted that the spat-catching lines will occupy less area
than fully-stocked mussel droppers (perhaps 2-3x due to turbulence?),
12 Plew DR, Stevens CL, Spigel RH, Hartstein ND (2005) Hydrodynamic implications of
large offshore mussel farms. Journal of Oceanic Engineering 30:95–108.
however, not 1,000’s to 10,000;s of times less; there is also some
ambiguity with respect to the size spat at harvesting that will impact on
roughness effects. In addition, and more importantly, while roughness is
an important factor for currents, it is an insignificant factor with respect to
wave-transmission.
7.9. In paragraph 38 of his evidence, Dr Beamsley states the impact of the
proposed spat catching is expected to be localised, and 2 paragraphs later
that there will be “no impact at any distance from the site”, although it is
uncertain how these conclusions were reached. I agree with Dr
Beamsley’s statement that there is little to no scientific information on the
impacts of marine farms on wave transmission, which makes it difficult to
understand how the conclusions with respect to distant impacts from the
proposed marine farms was determined. To my knowledge, other than
the current investigations to determine the impacts of salmon farm cages
on coastal processes and surf breaks due to the effects on wave
transmission in Tasmania, there are no existing or on-going investigations
into these impacts. Similar investigations linked with monitoring are
required to determine the effects to surf breaks due to nearshore marine
farms at Whauwhau Bay.
7.10. Appendix E “Consent Conditions and Monitoring” from the
Management Guidelines for Surfing Resources13 highlights potential
negative impacts of wave attenuation and provides outlines and examples
to appropriately design monitoring to determine and quantify impacts on
surf breaks where offshore aquaculture developments are within their
swell corridors, including a Case Study on Shellfish [farming] and surf
breaks. In the absence of any information, data or existing empirical
evidence that can be applied to the assessment of the impacts of wave
attenuation on the surf breaks in the lee of the proposed 3x 10 Ha marine
farms, it is my opinion that suitable and robust monitoring with adaptive
management should be developed for the site should any resource
consents be granted, which will require baseline investigations.
13 Atkin, E., Bryan, K., Hume, T., Mead, S. T., and Waiti, J., 2019. Management
Guidelines for Surfing Resources. Raglan, Aotearoa New Zealand: Aotearoa New Zealand
Association for Surfing Research. ISBN: 978-0-473-49540-4
7.11. With respect to local impacts, Dr Beamsley is incorrect with respect to
the understanding and studies directed at the effects of mussel farms on
local hydrodynamics. It is well known that due to conservation of
momentum, water flow is restricted through even small farms (Waite,
1989)14. Gibbs et al. (1991)15, Boyd and Heaman (1998)16 and Karayucel
and Karayucel (1998)17 observed reductions in flow through farms of up
to 70% compared to currents outside the farms. As with the potential
impacts on surf breaks in the lee of the proposed farms, there has been no
baseline data in the form of in situ current measures to determine what
velocities and directions of currents at the site in order to a) provide some
context to effects, and b) provide information on the orientation that
backbones with dropper lines should be placed in order to reduce impacts.
7.12. Potential effects on coastal processes are also linked to wave
attenuation. In a response to a submitter, Dr Beamsley states that “The
farm will not cause erosion”, although presents no evidence to support
this conclusion. In fact, if the impacts of the marine farm are found to be
manifest at the shoreline, then there is a realistic potential that the farm’s
presence will cause changes in local sediment transport due to changes in
wave height gradients, and consequently result in erosion of some areas of
the beach. Indeed, many of Dr Beamsley’s Responses to Submitters
claim that concerns around effects have been addressed in proceeding
points. This is not the case, for example, there is no information relating
to the tidal currents (strength/direction) and their interaction with a spat
catching structure.
8. EVIDENCE OF DR WILSON
14 Waite, R. P., 1989. The Nutritional Biology of Perna canaliculus With Special
Reference to Intensive Mariculture Systems. Unpublished PhD thesis, University of
Canterbury, Christchurch, New Zealand.
15 Gibbs, M.M., James, M.R., Pickmere, S.E., Woods, P.H., Shakespeare, B.S., Hickman,
R.W. an Illingworth, J. (1991). Hydrodynamic and water column properties at six stations
associated with mussel farming in Pelorus Sound, 1984-85. New Zealand Journal of
Marine and Freshwater Research 25: 239-254.
16 Boyd, A.J. and Heasman, K.G. (1998). Shellfish mariculture in the Benguela system:
water flow patterns within a mussel farm in Saldanha Bay, South Africa. Journal of
Shellfish Research 17: 25-32.
17 Karayucel, S. and Karayucel, I. (1998). Estimating the carrying capacity of mussel raft
systems in two Scottish sea lochs. The Israeli Journal of Aquaculture- Bamidgeh 50: 12-19.
8.1. I am in broad agreement with Dr Wilson’s evidence in that a spat-capture
farm will have less impacts on water quality/phytoplankton composition
and benthic ecology than farms for on-growing mussels. Many of the
negative impacts from intensive shellfish aquaculture are due to over-
stocking in locations with low flushing and locating in very sheltered
waterways where the physical processes such as re-suspension and
dispersion by wave activity do not occur. I note that it is still unclear
whether the spat will be allowed to grow to ~40 mm (as Dr Wilson
states), or whether collection ropes will be transferred while spat are still
microscopic.
8.2. Dr Wilson recommends monitoring the sediment quality under the 3x 10
Ha farms every 2-years to “assess any measurable effects on the organic
content of the seabed from the spat farm”, and also recommends “this
monitoring cease after three cycles (i.e. 6 years) if the results do not show
ecologically significant sediment effects from the farm.” (3b of evidence).
However, I am unclear on his following recommendation “In my opinion,
both the habitat and the biota are unlikely to be sensitive to the limited
potential effects of spat farming and, therefore, I do not consider that any
benthic ecological monitoring is required.” (3c), since in order to
determine whether the results of the monitoring (assumed to mean organic
content) show “ecologically significant sediment effects from the farm”,
the benthic ecology requires monitoring also. In addition, it is well
known that changes to the organic content (increases) in the sediment
under marine farms directly effects the ecological communities in these
locations (as in Keeley et al., 2009, presented in Dr Wilson’s evidence18).
Reference has been made to the low cost of testing for organic enrichment
meaning that it is a preference, however, the low cost does not address the
inadequacies of the monitoring approach.
8.3. It is my opinion that ecological monitoring of a suitably robust nature (i.e.
BACI design) should be required as a condition of any consents granted.
I agree with Dr Wilson (and Dr Bell), in that if no significant impacts are
18 Keeley, N.; Forrest, B.; Hopkins, G.; Gillespie, P.; Clement, D.; Webb, S.; Knight, B.;
Gardner, J. 2009. Sustainable aquaculture in New Zealand: Review of the ecological
effects of farming shellfish and other non-finfish species. Cawthron Report No. 1476. 150p
detected after three monitoring phases (6 years), benthic monitoring could
be ceased unless any significant changes to the spat-capture operation are
made.
9. CONCLUSION
9.1. The piecemeal approach to the provision of information pertaining to the
proposed marine farm and its potential environmental effects and the
deficit of data for the site have made it difficult to evaluate the application
and AEE.
9.2. Some ambiguity remains with respect to several aspects of the proposal
(e.g. effects to marine mammals, efficacy of the location for spat
collection, design of the mooring system), especially with respect to
impacts on surf breaks and coastal processes, and how the monitoring of
organic enrichment will be related to impacts on benthic ecology.
9.3. The surf breaks in the lee of the proposed marine farms have not be
characterised and little no site-specific information has been used to
determine potential impacts, while it is uncertain how a risk assessment
was undertaken in the absence of site-specific information. Similarly, the
effects changes to local hydrodynamic and wave characteristics have been
poorly addressed, again partially due to the lack of site-specific
information/data.
9.4. It is unknown how monitoring of organic enrichment under the farms will
be used as a proxy for monitoring of impacts to benthic communities.
Similar to determining ecological impacts by measuring organic
enrichment, it is not possible to go back in time and collect monitoring
data once you detect an impact, this is why robust and useful monitoring
should follow a procedure that can detect impacts at the site in question
(i.e. a BACI monitoring design).
9.5. The New Zealand Coastal Policy Statement states that we should manage
coastal resources with a precautionary approach towards proposed
activities whose effects on the coastal environment are uncertain,
unknown, or little understood, but potentially significantly adverse. Ms
Britton has suggested that “Policy 3.4.1 supports a precautionary
approach to activities whose effects are unknown or little understood.
Policy 3.4.2 seeks to avoid adverse effects on the shore and off-shore from
the activity. The opinion that a precautionary approach is not required is
discussed in paras 410 and 422.” With the basis for not requiring a
precautionary approach being “I rely on the evidence of Dr Beamsley that
there will be no effects on the shore from the presence of the spat catching
farm”. However, as detailed above, Dr Beamsley’s evidence provides no
actual information to support this opinion. It is my opinion that the
potential impacts on the surf breaks and coastal processes have not been
adequately investigated in order to determine the magnitude of effects,
and so a precautionary approach should be undertaken. It is noted that
there are no similar sites/activities in New Zealand that can be compared
to the current proposal.
Shaw Mead
1 December 2019
A Review of the Assessment of Environmental Effects for a Commercial Marine (Mussel Spat) Farm at Mercury Bay
A Review of the Assessment of Environmental Effects for a Commercial Marine (Mussel Spat) Farm at Mercury Bay
Report Status
Version Date Status Approved by
V1 21st November 2019 Draft STM
V1 22nd November 2019 Final Draft SDG
It is the responsibility of the reader to verify the version number of this report.
Authors
Edward Atkin, HND, MSc
Shaw Mead, BSc, MSc, PhD
Jai Davies-Campbell, BSc, MSc
The information contained in this document, including the intellectual property, is
confidential and propriety to Ecological and Physical Coastal Consultants Limited (T/A
eCoast). It may be used by the persons to whom it is provided for the stated purpose for
which it is provided and must not be imparted to any third person without prior written
approval from eCoast. eCoast reserves all legal rights and remedies in relation to any
infringement of its right in respects of its confidential information. eCoast 2019.
Whauwhau Mussel Spat Farm AEE Review
i
Executive Summary
The operators of a commercial green-lipped mussel farm have applied to Waikato Regional
Council (WRC) for a resource consent to establish and operate a commercial mussel spat
collecting operation adjacent to Whauwhau Beach in Mercury Bay. The application is for a 30
Hectare area made up of 3, 10 Hectares blocks, less than 2 km from the shore, in
approximately 20 to 25 m of water. This document is the synthesis of a review of the resource
consent application, Assessment of Environmental Effects (AEE) and other supplementary
information.
The officers report indicates that deficiencies in the application and AEE will be addressed at
the hearing, which provides some uncertainty with respect to addressing the issues identified
by our review (as well as other reviewers and submitters). However, several issues will likely
remain:
• Impacts on coastal processes and the 3 surf breaks in the lee of the three 10 Ha
spat collection blocks. Dropper ropes along the backbones (x11 at 20 m intervals)
in each block will extend to ~15 m, that is ~75% of the water column. These will have
similar impacts as have been investigated for mussel farms; redirecting currents and
dampening short period waves (the latter of which are dominant on the north eastern
coast of New Zealand). The significance of these impacts has not been addressed by
the applicant, which makes it difficult to determine what they may be and the magnitude
of them. It is important to note that swell corridor mapping is not for the assessment of
impacts to surf breaks, it is to indicate whether or not there is the potential to impact
on a surf break, and if so, flag requirements to assess the potential impacts;
• Risks to marine mammals. It is known that marine mammals have become entangled
in ropes in New Zealand associated with fishing and aquaculture practices. It is
proposed that this risk will be mitigated by ensuring the spat-ropes will be kept tight,
although it is unclear how this will be achieved and how this will alleviate this threat.
• Monitoring of benthic impacts. At present, the ecological assessment is very sparse
with respect to data/sampling locations, does not provide a good description of the
benthic community or evaluate its biodiversity, and so cannot be considered adequate
as a baseline survey. In addition, in order to measure effects at a potential impact site
(i.e. the benthic ecology under the spat collection blocks), time-series data of the
potential impact site has to be compared against control data, that is from a site with
similar physical and biological properties that is outside the zone of potential impact. A
standard BACI (Before/After, Control/Impact) monitoring approach is required. The
existing information presented in the AEE is insufficient for impact monitoring, and at
Whauwhau Mussel Spat Farm AEE Review
ii
best will only detect change that will not be able to be attributed to the activity and so
will likely be written off as ‘natural variation’;
• Uncertainty with respect to the efficacy of the selected site as a spat-collection
area. There are conflicting views by local submitters as to whether mussel spat
settlement occurs in large and regular numbers at the site. Pilot studies would provide
some direction with this respect. Should the activity go ahead, conditions that ensure
that the buoys, back-bones and anchors be removed in the event of low spat
recruitment, should be included in the consent.
Whauwhau Mussel Spat Farm AEE Review
iii
Contents
Executive Summary ............................................................................................................... i
Contents ............................................................................................................................... iii
Figures .................................................................................................................................. iv
1 Introduction .................................................................................................................... 5
2 General Comments ........................................................................................................ 6
3 Benthic Ecology ............................................................................................................. 9
4 Marine Mammals ......................................................................................................... 11
5 Biosecurity ................................................................................................................... 12
6 Physical Processes ...................................................................................................... 14
7 Surfing Resources ....................................................................................................... 15
8 Sea Change – Tai Timu Tai Pari .................................................................................. 16
9 Structure Specification ................................................................................................. 17
10 Monitoring ................................................................................................................ 17
11 References ............................................................................................................... 19
Appendix A. Known Surfing Coastlines in the Waikato Region ......................................... 1
Whauwhau Mussel Spat Farm AEE Review
iv
Figures
Figure 1.1. Locality maps. Top Left – Coromandel Peninsula. Top Right – Mercury Bay. Bottom
– proposed aquaculture footprint (Red) and Known Surfing Coastline (Green; see Atkin, 2017)
(Images from Google Earth). ................................................................................................. 5
Figure 3.1: Replication of the bathymetry, sampling locations and spat collection areas form
the AEE............................................................................................................................... 10
Whauwhau Mussel Spat Farm AEE Review
5
1 Introduction
The operators of a commercial green-lipped mussel (Perna canaliculus) farm located in the in
the Firth of Thames (Figure 1.1), have applied to Waikato Regional Council (WRC) for a
coastal permit type resource consent (Application No. 139219). The requested coastal permit
is to establish and operate a commercial mussel spat collecting operation adjacent to
Whauwhau Beach in Mercury Bay (Figure 1.1), with the aim of supplying existing, adult mussel
farms in the Firth of Thames with spat. The application is for a 30 Hectare area made up of 3,
10 Hectares blocks, less than 2 km from the shore, in approximately 20 to 25 m of water.
Accompanying the resource consent application is an Assessment of Environmental Effects
(AEE).
Figure 1.1. Locality maps. Top Left – Coromandel Peninsula. Top Right – Mercury Bay. Bottom – proposed aquaculture footprint (Red) and Known Surfing Coastline (Green; see Atkin, 2017) (Images from Google Earth).
Whauwhau Mussel Spat Farm AEE Review
6
eCoast has been engaged to evaluate the suitability of the information supplied to WRC for
the resource consent following local residents of Mercury Bay raising concerns about both
biosecurity and the impacts of the proposed structures on coastal processes. The review will
be undertaken in the context of the Resource Management Act 1991 and the New Zealand
Coastal Policy Statement 2010 (NZCPS) and will focus on issues associated to biosecurity
and coastal processes, as well as any other issues that become apparent with respect
environmental impacts. In addition, the S42A Report supplied by WRC, which recommends
the application be granted. This report is broken down in to 10 sections, each addressing an
aspect of the AEE and supplementary information.
2 General Comments
The Assessment of Environmental Effects (AEE) concludes that “the proposed farm block in
the location being sought would not create any "significant adverse effects" on the
environment” and that effect on the ecosystem “would be less than minor and such a farm
would be ecologically sustainable in the long term”. However, on reviewing the available
material, it is clear that there are key components missing from the AEE.
The AEE states “it is clearly farming a renewable resource; and will support high water quality”.
It is unknown whether this is a sustainable resource as no studies have been undertaken,
such as spat-fall viability; the AEE lacks any scientific evidence relating to the quantities of
spat in Mercury Bay. There is no information regarding marine community connectivity, and
what role spat on the East Coast of the Coromandel play. There is no information regarding
the likely species and/or processes (if any exist) that rely on the east Coromandel spat
population.
The AEE fails to specify or estimate what mass of spat the operation intends to remove, and
what effects this may have on the existing environment. The only reference to the existing
east coast Coromandel spat population is the anecdotal evidence of the applicant who “is
aware from their combined experiences and local knowledge that there are adult mussels in
the vicinity of the proposed application area and that spat spawn occurs naturally in this area”.
Although this is contrary to submissions from local submitters. In addition, it appears that the
viability of this activity is based the applicants being “confident through local knowledge and
experience that there are sufficient populations of adult mussels in the area to support a spat
catching facility of the size proposed”, and not on robust science, either through existing
published literature of site-specific investigations.
Whauwhau Mussel Spat Farm AEE Review
7
Policy 3 of the NZCPS states that we should manage coastal resources with a precautionary
approach towards proposed activities whose effects on the coastal environment are uncertain,
unknown, or little understood, but potentially significantly adverse. In the present case, the
effects remain uncertain, unknown and there is little understanding due to inadequate
investigations. The AEE attempts to address this with the statement “that it is expected that
any effects resulting from the proposal will be difficult to measure”. However, very little attempt
has been made to quantify the impacts from a physical or biological perspective, and the
monitoring that is proposed that would assist in addressing this is not fit for purpose.
At present, the ecological assessment is very sparse with respect to data/sampling locations,
does not provide a good description of the benthic community or evaluate its biodiversity, and
so cannot be considered adequate as a baseline survey. In addition, in order to measure
effects at a potential impact site (i.e. the benthic ecology under the spat collection blocks),
time-series data of the potential impact site has to be compared against control data, that is
from a site with similar physical and biological properties that is outside the zone of potential
impact. A standard BACI (Before/After, Control/Impact) monitoring approach is required. The
existing information presented in the AEE is insufficient for impact monitoring, and at best will
only detect change that will not be attributable to the activity and so will likely be written off as
‘natural variation’.
It should also be noted that this proposed commercial activity is ~3.5 km from Te Whanganui-
A-Hei Marine Reserve, which was established in 1992. It is widely recognised that marine
reserves are effective in restoring marine ecosystems, and the benefits of Te Whanganui-A-
Hei Marine Reserve have been well reported (Haggitt and Mead, 2006); it is also only ~2 km
from Motukoranga Island, an area of outstanding natural character.
The AEE states that “Ngati Hei Kaitiakitanga will adhere to the core principle that sustainability
and abundance must be essential in the ongoing development of environmentally sustainable
aquaculture as we grow, learn, mature and evolve into the business of aquaculture’. In its
current form, this application and AEE cannot be considered suitable for underpinning the
activity as sustainable due to a lack of understanding of the receiving environment.
The AEE is largely focussed on the adult mussel aquaculture, which is understandable given
the applicants background (commercial adult mussel producer). However, this does not
compensate for a lack of understanding in biological, chemical and physical effects that spat-
capture blocks have the potential to lead to, or/and the associated impacts on the wider
Mercury Bay environment.
For example, impacts on coastal processes and the 3 surfing breaks in the lee of the 3x 10
Ha spat collection blocks have not been appropriately addressed. Dropper ropes along the
Whauwhau Mussel Spat Farm AEE Review
8
backbones (x11 at 20 m intervals) in each block will extend to ~15 m, that is ~75% of the water
column. These will have similar impacts as have been investigated for mussel farms;
redirecting currents and dampening short period waves (the latter of which are dominant on
the north eastern coast of New Zealand). The significance of these impacts has not been
addressed by the applicant, which makes it difficult to determine what the impacts may be and
the magnitude of them. It is important to note that swell corridor mapping is not for the
assessment of impacts to surf breaks, it is to indicate whether or not there is the potential to
impact on a surf break, and if so, flag requirements to assess the potential impacts
Biosecurity information regarding invasive species are considered in Section 4. However, the
AEE reports that the “greatest risk of spreading invasive species such as Undaria, Corella or
Mediterranean fan worm are recreational vessels visiting the Mercury Bay area that have
come from locations known to be infested with these pests, such as Whangarei, Waitemata
Harbour and the Hauraki Gulf. The presence of a mussel spat catching facility or farm
structures is no more likely to introduce alien species than mussels on rocks would introduce
alien species”. While this maybe be true, it cannot be taken as an endorsement for the
proposed activity; just because the introduction of invasive species cannot be regulated due
to one type of activity, this should not mean all activities can be undertaken.
People who are recognised as having experience in various fields of marine science have
provided to the applicant and WRC reviews of the application and various addendums. They
also raise concerns over the suitability of the application and scarcity of reliable detail. From
Dr Jacqui Bell:
• the supplementary report does not sufficiently address the possible effects on habitat
modification and exclusion of marine mammals.
• The assessment does not consider the effects of underwater noise sufficiently
• There is no coastal processes assessment associated with this application
• It is my opinion that this application does not sufficiently address the risk of adverse
effects due to invasive species incursion and the management of this risk. This
application needs to include a biosecurity management plan outlining the actual risk of
spread of invasive species from nearby affected areas, the level of fouling acceptable
on vessels and equipment prior to entering and exiting the spat catching facility and a
protocol for inspection and cleaning.
And from the AEE itself:
• “Dr Bell considers that the description and assessment of the existing habitat is
somewhat lacking.”
• “Dr Bell acknowledges that the survey methodology is lacking”
Whauwhau Mussel Spat Farm AEE Review
9
And Dr Stephen Hunt:
• The consultant mentions that:
“The permanently moored surface ropes do not extend into the water column and are
very unlikely to have any effect on wave action or tidal currents.” This statement is not
necessarily true…..
• I am not aware of any evidence that demonstrates the orientation of the tidal
flow………the applicant’s evidence is more based on opinion than actual
hydrodynamic evidence.
In summary, there are numerous short comings in this application that have not only been
noted by largely untrained submitters against the application, but the applicant’s reviewers,
and the consenting authorities in house advisors.
3 Benthic Ecology
Benthic ecology sampling was undertaken by Discovery Marine Limited, with the assessment
undertaken by Pacific Coastal Ecology (S. White). The methodology in the AEE describes the
collection of 9 samples, 3 in each of the 10 Hectare blocks, with a 250 mm x 150 mm box
dredge, as well as 3 video transects in the middle of each of the proposed blocks. While these
are appropriate methods of data collection, the level of intensity is very low. For example, the
grab samples represent approximately an area sampled of 0.000012 % of the total proposed
area. Similarly, a single screenshot of the dropcam drift video is provided as evidence of the
seabed type, while the features in the sidescan remain ambiguous.
The sampling strategy is insufficient, unconventional and lacks any justification. The AEE
states that “Dr Bell acknowledges that the survey methodology is lacking” and “considers that
the description and assessment of the existing habitat is somewhat lacking.”
There is no description of how the discrete sampling points were established. While in Figure
3.1 there is slight depth stratification in sampling due to the natural gradient of the seabed and
its alignment with the design footprint of the structure, a more comprehensive approach would
have maximised this gradient for each of the 10 Hectare blocks, as well as stratified for
substrate type. There is very little depth stratification in sample area B. Sample B3 is
completely outside of the proposed block area. It is unclear if this was intentional.
At present, the ecological assessment of the AEE is very sparse with respect to data/sampling
locations, does not provide a good description of the benthic community or evaluate its
biodiversity, and so cannot be considered adequate as a baseline survey. In addition, in order
Whauwhau Mussel Spat Farm AEE Review
10
to measure effects at a potential impact site (i.e. the benthic ecology under the spat collection
blocks), time-series data of the potential impact site has to be compared against control data,
that is from a site with similar physical and biological properties that is outside the zone of
potential impact. A standard BACI (Before/After, Control/Impact) monitoring approach is
required. The existing information presented in the AEE is insufficient for impact monitoring,
and at best will only detect change that will not be attributable to the activity and so will likely
be written off as ‘natural variation’.
Figure 3.1: Replication of the bathymetry, sampling locations and spat collection areas form the AEE.
Whauwhau Mussel Spat Farm AEE Review
11
4 Marine Mammals
The Hauraki Gulf is home to many species of whale and dolphin. The three most commonly
observed species are Bryde’s (Balaenoptera edeni), Sei (Balaenoptera borealis) and Pygmy
blue whales (Balaenoptera musculus brevicauda). Bryde’s Whales have a conservation status
of Nationally Critical and an IUCN status of threatened. There are less than 200 Bryde’s
whales living in New Zealand all of which live in or very close to the Hauraki Gulf Marine Park.
Sei Whales have a conversation status of migrant in New Zealand and an IUCN status of
endangered. Sei whales are migratory and are found in most of the world’s oceans. Pygmy
blue whales have a conservation status of migrant and an IUCN status of data deficient.
Dolphins are a common sight in the Hauraki Gulf. The three most commonly observed
dolphins seen are the Common Dolphin (Delphinus sp.), which are not threatened, the
Bottlenose dolphin (Tursiops truncates), which is regarded as Nationally Endangered but has
an IUCN status of “least concern”, and Ocra (Orcinus ocra), which has a conservation status
of Nationally Critical and has an IUCN status of data deficient. A small population of Ocra, less
than 200, reside in New Zealand and these Orca visit the Gulf in pods of between 5 and 15
individuals. The New Zealand Fur Seal is also a common sighting within the Hauraki Gulf.
The interactions between marine mammals and anthropogenic activities usually result from
an overlap between the location and/or timing of the activity with important habitats of the
species. The direct effects of such overlap range from physical interactions with the animals
(e.g. vessel strikes) to avoidance or even abandonment of the area by the species due to the
general increase in activity (e.g. noise or traffic). Indirect effects may result from physical
changes to the habitat itself that adversely affect the health of the local ecosystem and/or
impinge on important prey resources.
With respect to impacts from the proposed activity, the following can be considered:
• Increased risk of marine mammal/vessel strike due to increased vessel traffic during
construction, deployments and retrievals;
• Increased risk of marine mammal/vessel strike due to increased vessel traffic due to
increased fishing activity;
• Increasing underwater noise levels has the potential to negatively affect both
cetacean and pinniped species as they rely on underwater sounds for
communication, orientation, predator avoidance and foraging, and;
• Marine mammal habitat/prey loss from damage/disturbance to the seabed due to
cable laying activities.
Whauwhau Mussel Spat Farm AEE Review
12
The AEE states that “…studies suggest that while some marine mammal species are not
completely displaced from regions as a whole, they do not appear to be utilising habitats
occupied by shellfish farms in the same manner as prior to the farm’s establishment.”. While
the impact may be low, the AEE provides no evaluation of what the consequence could be;
how any resident pinnipeds or dolphins may be affected; what times of year any particular
species visit the bay; potential mitigation options such as keeping activities reduced during
certain times of year to allow uninterrupted hunting/foraging; and what operating procedures
could be followed should charismatic mega fauna be spotted. The AEE states that “It is likely
that the proposed spat catching facility would result in considerably reduced habitat exclusion
effects on marine mammals”.
It is known that marine mammals have become entangled in ropes in New Zealand associated
with fishing and aquaculture practices. It is proposed that this risk will be mitigated by ensuring
the spat-ropes will be kept tight. Dr Bell states that “I am unclear on how the applicant intends
to ensure that dropper lines are tight”. Indeed, it is unclear how this will be achieved and how
this will actually alleviate this threat. Also, from Dr Bell “there is a lack of reliable information
on the distribution of marine mammals in the Mercury Bay area. The report uses this as a
basis for there being no likely effect and no need for mitigation” and “the assessment does not
consider the effects of underwater noise sufficiently.”. These are further examples of
deficiencies in the AEE, and how a lack of understanding is being used as justification for
evaluating potential effects as being low. This is not in line with the purpose of the RMA or
NZCPS.
5 Biosecurity
Forest and Blakemore (2006) and Forrest et al. (2007) provide information on the
requirements to eradicate Undaria gametophytes. They state that 100% mortality has been
achieved via high pressure spraying (2000 psi for 2s and 3000 psi for 1-2s), freshwater
immersion (2 days at 10°C), air drying (2-3 days at 10°C), hot water immersion (35°C for
10min, 45°C for 45s, 55°C for 5s), and acetic acid (0.1-2% for 1 minute) (Forrest & Blakemore
2006, Forrest et al. 2007). There is a void in this type of information in the applicants AEE;
which states that equipment stored on land for a few weeks and cleaned would “effectively be
clean in a biological sense”.
From the S42A report, and following the recommendations of Dr Jacqui Bell, the applicant
plans to construct a Biosecurity Management Plan. The S42A report states that:
“A biosecurity management plan shall include but not be limited to:
Whauwhau Mussel Spat Farm AEE Review
13
a) Details of the marine pests, unwanted and notifiable organisms and marine fouling
organisms, identified by the Ministry for Primary Industries (MPI), Waikato Regional
Council and the marine farming industry, as priority species that are to be identified
and recorded.
b) Details of the processes which would be applied by farm operation staff to identify,
record and report on species identified in (a) as well as any species new to the area.
This would include at least the date of observation, organisms observed and extent of
infestation.
c) Measures that would be undertaken to educate and train farm operation staff on
biosecurity requirements and responsibilities.
d) Measures that would be undertaken to:
i. avoid the introduction, exacerbation and spread of species identified in (a);
and
ii. actions that would be undertaken if any new organisms are observed.
e) Process, subject matter and timing of reporting to Council.
f) Process and timing for reviewing and updating the biosecurity management plan.”
The S42A report states that “the (biosecurity management) plan shall be submitted to the
Waikato Regional Council for written approval in a technical certification capacity. The plan
shall be submitted at least 1 months prior to placing any structures in the coastal marine area”.
At time of writing, the BMP, an integral piece of operating procedure, is not available for an
assessment for either WRC or other stakeholders.
It is proposed that the staff who service the spat catching facility will be trained in identifying
any new or unusual species. The level of training that staff will receive has not been specified
and the level of difficulty and time requirements to undertake this task are unknown. It is
unclear how the subtidal environment will be evaluated by operational staff.
The further information document states the applicant is “interested to know what practices
other users i.e. commercial long liners/seiners, scallop dredgers and recreational users
undertake to stop the spread of unwanted pests? And queries if they have another processes
that could be incorporated to improve their biosecurity”. A prudent consent application and
associated AEE, focussed on a sustainable activity, would have answered these queries and
considered best environmental practice before submission.
Whauwhau Mussel Spat Farm AEE Review
14
6 Physical Processes
The extent to which the AEE has considered physical processes is in the form of an email
letter from Ms Bronwen Gibberd, which is based on a review of the AEE and Surf Breaks of
Regional Significance in the Waikato Region (Atkin and Mead, 2017). Ms Gibberd concludes
that any effects of these ropes on coastal processes are likely to be minor and localised.
It is unclear how these conclusions have been reached given the scarcity of actual physical
processes data with in the AEE. There is no quantitative information about tidal currents
(direction and strength), a void of wave climate information, and no consideration for general
hydrodynamics. This does however explain the lack of discussion around physical processes,
most notably the absence of any mention of sediment transport pathways either in regard to
the environmental setting or whether the proposed activity would have an effect.
WRC’s coastal scientist, Dr Stephen Hunt, has reviewed the comments made by Ms Gibberd
about coastal processes, and noted that he is “not aware of any evidence that demonstrates
the orientation of the tidal flow”. In order to minimise the impacts on current speeds and
directions, it is necessary to measure them onsite in order to understand their direction and
velocity; this is a fundamental piece of information absent from the AEE.
In the AEE itself, there is limited discussion on the effects of long-line mussel farms. The AEE
considers the work of Plew et al. (2005), who found a 38% decrease in current speed and a
reorientation of water flow parallel to the alignment of the mussel lines at peak velocities. Plew
et al. (2005) also found that wave energy was attenuated across their single study site. The
AEE notes that technological changes in recent years has seen the introduction of swell
reduction "springs". In this setting it is assumed that wave climate will play a significant role in
coastal morphodynamics of Mercury Bay. Beyond the limited study of Plew et al. (2005) there
are very few studies that have considered wave-mussel farm interactions; in addition, the Plew
et al. (2005) study is not transferrable to this case in terms of physical oceanography, farm
sizes and stocking/drop-rope densities. This again highlights the importance of Policy 3 of the
NZCPS (Adopt a precautionary approach towards proposed activities whose effects on the
coastal environment are uncertain, unknown, or little understood).
Whauwhau Mussel Spat Farm AEE Review
15
7 Surfing Resources
The extent to which the AEE has considered surfing resources is in the form of an email letter
from Ms Bronwen Gibberd, which is based on a review of the AEE and the report entitled Surf
Breaks of Regional Significance in the Waikato Region (Atkin and Mead, 2017). The email
from Ms Gibberd states that she was requested by WRC to review the Surf Breaks of Regional
Significance in the Waikato Region report. Ms Gibberd concluded that “the location of the
proposed farm is sheltered from the north/northeast by the Kuaotunu Peninsula and is outside
of the path of any distantly generated waves propagating towards Whitianga or any other
beaches and that the report identifies swell corridors for the surf breaks, combined these swell
corridors cover almost all of the territorial sea of the eastern Coromandel. The proposed spat
farm is one of only a few small areas outside of these swell corridors”.
Dr Stephen Hunt, WRC’s coastal scientist, comments concur with Ms Gibberd’s. It is important
to note that swell corridor mapping is not for the assessment of impacts to surf breaks, it is to
indicate whether or not there is the potential to impact on a surf break, and if so, flag
requirements to assess the potential impacts in more detail. The function of the swell corridor
management tool, which has worked well in this case, is to indicate whether or not there would
be an effect on the Surf Breaks of Regional Significance in the Mercury Bay proximity.
However, a critical piece of information, that has been overlooked in the dialogue between
WRC and Ms Gibberd, and Dr Hunt’s subsequent review, is the addendum letter report of
Atkin (2017), Known Surfing Coastlines in the Waikato Region (Appendix A).
The Known Surfing Coastlines in the Waikato Region addendum (Atkin, 2017) considered the
abundant, lesser known surf breaks and surfing areas, also known as “Secret Spots”, in the
Waikato Region. An issue that surrounds surfing and surf breaks worldwide is the desire of
surfers to keep the number of participants at a surf break to a minimum. Secret Spots, which
are perceived as being known to a few, are described as closely guarded and/or challenging
to access. These surf breaks are coastal resources that also need to be considered during
coastal management and decision making (Orchard et al., 2019). It was proposed and agreed
with WRC that Known Surfing Coastlines (KSCs) were identified and defined; with the aim of
concealing specific details regarding the surf breaks and maintaining their “secret” status. At
the same time this method bookmarked their existence should management decisions
concerning a section of coast be required. This approach has been considered analogous to
the ‘silent file’ approach used by Ngāi Tahu for culturally sensitive sites (Tau et al. 1990;
Orchard et al., 2019).
Figure 1.1 shows the KSC data, “Devils Point-Tohetea Stream” provided to WRC as part of
the Known Surfing Coastlines in the Waikato Region report. There are at least 6 locally
Whauwhau Mussel Spat Farm AEE Review
16
significant surf breaks in the Devils Point-Tohetea Stream KSC, 3 of which are within ~2 km
of the proposed structure. It is highly likely that these structures will be within the swell
corridors of at least 3 of these surf breaks. It should be noted that Section 7 - Sea Change –
Tai Timu Tai Pari considers the application with the context of the Hauraki Gulf Marine Spatial
Plan (HGMSP); the plan does not delineate the significance of surfing resources and makes
no reference to Surf Breaks of National Significance, Surf Breaks of Regional Significance or
other specification, but just “known surf breaks”.
Section 5 of this report considers physical processes, including the potential to decrease wave
height and alter current directions in and around the structure; with both the documented
decrease in wave energy of lower periods waves and the introduction of “swell reduction
springs” being some concern. The surf breaks inside the KSC have not been identified or
characterised by the applicant, so at this stage it is not possible, along with the scarcity of any
wave climate data in the AEE, to effectively evaluate any potential effect.
A fundamental flaw in the AEE and subsequent assessments, is a lack of stakeholder
engagement regarding surfing resources, one of the first steps recommended in the
Management Guidelines for Surfing Resources (Atkin et al., 2019). The guidelines also
recommend that consent applicants approach the local authority for all available resources.
8 Sea Change – Tai Timu Tai Pari
The AEE for this consent notes that the Hauraki Gulf Marine Spatial Plan (HGMSP) identified
the proposed area as being a suitable location for aquaculture, specifically, subtidal shellfish
(mussels and fish). The HGMSP states that the 13 areas identified as suitable for aquaculture
were done so with the “expectation that further investigation will be undertaken on a place-by-
place basis to identify potential benefits and effects and to further define the boundaries”.
While an AEE has been undertaken, it is shown in each section of this report that there are
many shortcomings in understanding potential effects. The aquaculture area proposed in the
HGMSP appears to be based more on a design specification than an area designated through
a robust, science based process to determine a suitable area for sustainable aquaculture type
activities to take place; and no attempt to “further define the boundaries” has been made.
Whauwhau Mussel Spat Farm AEE Review
17
9 Structure Specification
Little no information is provided regarding the hardware that will make up the proposed spat
catching structure. Of importance would be the pull-out and shear weight, or holding power of
anchors, and the tensile strength or minimum breaking load of mooring lines. Whilst this
information would be useful for tentatively assessing the suitability of hardware, without any
information or data pertaining to the environmental setting relating to hydrodynamics and
extreme wave events, the suitability of the structure cannot be assessed.
10 Monitoring
Given the amount of uncertainty in the AEE, a very stringent monitoring plan should have been
recommended, one that would allow for an adaptive management approach; one that is based
on a comprehensive baseline. Conversely, “the applicant contends that the scale and
significance of effects from spat catching is minimal and that the level of monitoring required
of other full marine farms is not warranted”.
While the AEE does recommend monitoring be undertaken, it fails to recognize that for
monitoring to have any relevance it needs to be within the context of the existing environment
which is clearly not possible by proposing “that such monitoring would be best commenced
once the farm has been established and spat is being caught “. The AEE refers to the sparse
data collected to date as “baseline”. A singular set of low frequency, discrete samples that fails
to provide a good description of the benthic community or evaluate its biodiversity, 3
subsurface camera transects, and a bathymetric survey is not a baseline dataset. The AEE
states that monitoring could be completed on a 5-yearly basis. In a 35-year consent that is just
7 times.
A more appropriate monitoring frequency would be before and after every installation of the
spat catching lines for at least the first 5 years. However this should only follow on after a
baseline has been established that is based on more industry standard and comprehensive
datasets, which, following other precedents for baseline establishment, would be a minimum
of 1 year (noting a multiyear baseline dataset would underpin the values of sustainability
described by Hgati Hei and Sea Change – Tai Timu Tai Pari).
The AEE describes what ongoing monitoring could include, and the type of tests that could be
undertaken. There is no description of actions that would be taken if changes are detected.
The monitoring does not describe how natural change will be detected against anthropogenic
impact. The AEE fails to consider the use of a control (comparison) site for monitoring
Whauwhau Mussel Spat Farm AEE Review
18
purposes – a fundamental component of environmental monitoring, and any science-based
investigation. Furthermore, the recommended monitoring is focussed on the site of the activity
itself and does not consider the shorelines and subtidal reefs adjacent to the proposed
structure.
The AEE’s proposed monitoring is focussed on water quality and benthic communities. While
understanding if there are any changes to these parameters is important, the impacts
associated with extracting a percentage of juveniles from an existing population of one species
with unknown biomass is not considered within the monitoring framework. Noting that the
objectives for aquaculture in Sea Change include well targeted and sensible monitoring of
aquaculture is carried out and is integrated with Gulf wide state of the environment monitoring.
Whauwhau Mussel Spat Farm AEE Review
19
11 References
Atkin, E.A., 2017. Known surfing coastlines in the Waikato region. Raglan, New Zealand:
eCoast Marine Consulting and Research. Letter Report, Waikato Regional Council.
Atkin, E., Bryan, K., Hume, T., Mead, S. T., and Waiti, J., 2019. Management Guidelines for
Surfing Resources. Raglan, Aotearoa New Zealand: Aotearoa New Zealand Association for
Surfing Research. ISBN: 978-0-473-49540-4
Atkin, E., and Mead, S. T., 2017. Surf breaks of regional significance in the Waikato region.
Technical Report produced for Waikato Regional Council.
Forrest, B. M., & Blakemore, K. A. (2006). Evaluation of treatments to reduce the spread of a
marine plant pest with aquaculture transfers. Aquaculture, 257(1-4), 333-345.
Forrest, B. M., Hopkins, G. A., Dodgshun, T. J., & Gardner, J. P. A. (2007). Efficacy of acetic
acid treatments in the management of marine biofouling. Aquaculture, 262(2-4), 319-332.
Haggitt T. and S. T., Mead, 2006. Te Whanganui-a-Hei Marine Reserve Biological Monitoring
Programme: May-June 2006 Survey. Prepared for the Department of Conservation, Waikato
Conservancy, August 2006.
Orchard, S; Atkin, E.A., and Mead, S.T., 2019. Development of the regional significance
concept for surf break management in Aotearoa New Zealand. In: Bryan, K.R. and Atkin, E.A.
(eds.), Surf Break Management in Aotearoa New Zealand. Journal of Coastal Research,
Special Issue No. 87, pp. 23-34. Coconut Creek (Florida), ISSN 0749-0208.
Plew DR, Stevens CL, Spigel RH, Hartstein ND (2005) Hydrodynamic implications of large
offshore mussel farms. Journal of Oceanic Engineering 30:95–108
Tau, T.M.; Goodall, A.; Palmer, D., and Tau, R., 1990. Te Whakatau Kaupapa – the Ngāi Tahu
resource management strategy for the Canterbury region. Christchurch, New Zealand: Aoraki
Press, 252p.
Whauwhau Mussel Spat Farm AEE Review
1
Appendix A. Known Surfing Coastlines in the
Waikato Region
Whauwhau Mussel Spat Farm AEE Review
2
The Following is the letter report provided to Waikato Regional Council regarding Known
Surfing Coastlines. Please note that the figures and tables have been removed from this
report in order to maintain the purpose of the Known Surfing Coastlines.
eCoast Marine Consulting and Research
PO Box 151
Raglan,
New Zealand
Ph. +64 2108 200 821
www.ecoast.co.nz
3rd May 2017
Attn: Hannah Jones
Scientist – Coastal Ecology
Science and Strategy
Waikato Regional Council
Dear Hannah,
Re: Known Surfing Coastlines in the Waikato Region.
In 2015/2016 eCoast Marine Consulting and Research undertook a project for Waikato
Regional Council to identify the region’s Surf Breaks of Regional Significance, define their
associated Surf Break Areas (SBAs) and swell corridors, and, outline potential threats to
surfing amenity.
The primary method for determining if a surf break is regionally significant is inclusion in the
Wavetrack New Zealand Surfing Guide (WNZSG; Moorse and Brunskill, 2004; see
methodology in Atkin and Mead, 2017). A component of this project was to undertake local
consultation to determine if there are surf breaks in the Waikato region that are not included
in the WNZSG but should be considered regionally significant, noting that the WNZSG list is
not definitive, was published in 2004, and surf break discovery and increased usage continues.
For the original project (Atkin and Mead, 2017), Surf Breaks of Regionally Significance (SBRS)
outside of the WNZSG are defined as having a dependent population, whether it be local, non-
local, foreign or a mix of all; high frequency of use; and/or, are of outstanding natural
character/quality. Public consultation revealed an abundance of unnamed or not officially
Whauwhau Mussel Spat Farm AEE Review
3
recognised surf breaks and surfing areas; and that the number of frequented surf breaks was
more than that described in the WNZSG and other published surf break information sources.
These lesser known surf breaks were not found to meet the criteria of regionally significant.
However, they are coastal resources that should be considered during coastal management
and decision making.
An issue that surrounds surfing and surf breaks worldwide is the desire of surfers to keep the
number of participants at a surf break to a minimum. “Secret Spots”, which are perceived as
being known to a few, are described as closely guarded and/or challenging to access. Many
of the surf breaks made known to eCoast during local consultation fall under these two
categories. Given the subjective and protective nature associated with surfers, exposing surf
breaks that are not commonly known or spoken about may insight discord within the surf
community.
The chosen approach is to specify Known Surfing Coastlines (KSCs), were surf breaks along
these coastlines fall under the title of Surf Breaks of Local Significance (SBLS). With no data
pertaining to the quality of the waves, besides anecdotal evidence, or a method of determining
how often these surf breaks are surfed and by how many, it is not possible to designate them
as regionally significant. This approach is ambiguous and non-descript, with the aim of
concealing specific details regarding the surf breaks and maintaining their “secret” status. At
the same time this method bookmarks their existence should management decisions
concerning a section of coast be required.
Included in the KSCs are surf breaks that are known, or have been documented (e.g. Rainger,
2011), but have not previously been considered regionally significant (Atkin and Mead, 2017).
Table 1 presents a total of 21 KSCs for the Waikato region, 7 on the west coast, and 14 on
the east coast.
Figures 1 and 2 present the locations of the KSCs and correspond to Table 1.. The KSCs are
polygons constructed by taking subsections of Land Information New Zealand’s (LINZ)
1:50,000 coastline polygon and buffering by approximately 250 m (see Atkin and Mead, 2017).
The polygon does not represent a boundary to a surfing area (like an SBA), but is to make
viewing GIS data, and the relevant section of coast as user friendly as possible.
Where a Locally Significant Surf Break(s) was identified, the relevant KSC subsection is
delimited and named by prominent geographical features along the coast, similar to the
Whauwhau Mussel Spat Farm AEE Review
4
naming convention for nautical charts. For example, surf breaks were identified from Arataura
Point to Urawhitiki Point, as shown in Figure 3. In the case of Whakapenui Point to Cooks Bluff
KSC, the LINZ coastline was edited to remove the sections that make up the tidal inlets at the
west and east ends of Cooks Beach – as surfing is not possible in these areas
The KSCs function is to highlight sections of coast where surfing is known to be undertaken
and/or possible. The actual surfing area may be some distance offshore from the designated
coastline (e.g. an isolated rocky reef), however the GIS data provides the necessary
information to inform decision making processes.
The global surf population, and the list of surfing locations, is ever expanding with the surfing
community’s common theme of searching for unridden or infrequently used surf breaks. The
natural progression is for higher numbers of users at all breaks, including those currently used
by the few. Surf breaks that are currently considered locally significant may become regionally
significant in the future.
Concurrent with Atkin and Mead (2017), it is recommended that this list of KSCs for the
Waikato region should be revaluated: prior to each iteration of the coastal plan; and/or at a
time frame deemed suitable by Waikato Regional Council that allows for surf breaks to be
included as required; and, at any time the Waikato’s Surf Breaks of Regional Significance are
revaluated.
Please let me know if you require any more information.
Yours sincerely,
Ed Atkin | Director
References
Atkin, E. A. and Mead, S.T., 2017. Surf Breaks of Regional Significance in the Waikato Region.
eCoast Technical Report Prepared for Waikato Regional Council.
Moorse, P. B. and Brunskill, P., 2004. Wavetrack New Zealand Surfing Guide. Greenroom
Surf Media Ltd, Mount Maunganui.
Rainger, T., 2011. The New Zealand Good Beach Guide: North Island. Raglan: Clean Media
Ltd.