G:\Client Data\455328\247\D180406CPT-J Thomas Evidence Final.docx
BEFORE A SPECIAL TRIBUNAL UNDER SECTION 203 RESOURCE MANAGEMENT ACT 1991
UNDER the Resource Management Act 1991
IN THE MATTER of an application under Part 9 of the Act
AND
IN THE MATTER of an application for a water conservation order at Te
Waikoropupū Springs and associated water bodies
BY
NGĀTI TAMA KI TE WAIPOUNAMU TRUST AND
ANDREW YUILL
Applicant
AND TASMAN DISTRICT COUNCIL
Submitter
BRIEF OF EVIDENCE OF JOSEPH THEODORE THOMAS
6 APRIL 2018
FLETCHER VAUTIER MOORE LAWYERS
PO BOX 3029 RICHMOND 7050
Telephone: (03) 543 8301 Facsimile: (03) 543 8302
Email: [email protected] Solicitor: CP Thomsen
1
Introduction
1. My name is Joseph Theodore Thomas. I have been asked to give
expert hydrological evidence in respect of an application for a water
conservation order at Te Waikoropupū Springs and its contributing
waters.
Experience and Qualifications
2. I am the resource scientist water/special projects for the Tasman District
Council. I have held this position for ten years.
3. Prior to that (1992 – 2006) I held the position of Resource Scientist
Water, also with the Tasman District Council. I was a Groundwater
Officer with the Nelson-Marlborough Regional Council from 1989 to its
dissolution in 1992. From 1987 to 1989 I was a research assistant with
the Nelson Catchment and Regional Water Board, carrying out water
resources research in the Moutere Catchment as partial fulfilment for
the requirements (thesis) for my Masters Degree in Engineering
Geology at the University of Canterbury. I was a lecturer in soil
mechanics in the School of Civil Engineering at the Federal Institute of
Technology in Malaysia from 1985 to 1986.
4. I hold a Bachelors Honours Degree (Engineering Geology) from the
National University of Malaysia and a Masters (First Class Honours)
Degree in Engineering Geology from the University of Canterbury.
5. I am a member of the New Zealand Hydrological Society, the
International Association of Hydrological Sciences, National
Groundwater Association U.S.A. and the Geosciences Society of New
Zealand.
6. I have been the President of the New Zealand Hydrological Society
since 2010. Prior to being appointed president I was secretary of the
Society, holding the international liaison portfolio. Before that I was on
the Society’s executive committee.
7. I am actively involved with hydrological activities in New Zealand and
am involved in several science advisory and research interest groups. I
have presented papers on water resources investigation and
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management both within New Zealand and overseas, and have written
and co-written numerous papers in various published media and
journals. I contributed to writing a chapter on Tasman groundwater in
Groundwater’s of New Zealand published by the New Zealand
Hydrological Society in 2001.
8. My key role at the Council is the investigation, assessment and
management of the District’s water resources. I have been carrying out
this work in the catchments of the Tasman District since 1987 and I
have a good knowledge of its water resources. I also have
responsibility for strategic water resource investigations and project
management. This includes investigations into future water supply
needs and identifying sources and options for that supply, including
storage/augmentation.
9. I advise the Council’s Dry Weather Task Force during summer on
implementation and management of water restrictions across the
District. I actively oversee collection of summer-specific water resource
information (low flow gauging’s, groundwater levels and saltwater
intrusion monitoring) over that period.
10. In about 2008, I assisted the Special Tribunal for the Buller River Water
Conservation Order review. I guided the tribunal on the Gowan River
field visit and explained the hydrology of the river.
11. Specifically relevant to this application is my involvement with the
investigation and assessment of water resources in the Takaka
Catchment since 1989. Over this period I have been directly involved in
hydrological data collection and assessment, including rivers and spring
flow measurement, groundwater level monitoring, groundwater aquifer
testing, water take consent assessment/monitoring (metering of water
use) and groundwater quality assessment.
12. I was the Lead Technical Officer in the re-consenting of the Cobb
Hydropower Scheme in Takaka. This consent was lodged in 2001 and
heard by Commissioners in early 2003 who granted the consents. Upon
appeals and subsequent mediation, final resolution was through a
consent order issued by the Environment Court in 2004. I worked
closely from the start of the re-consenting investigation from the late
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nineties with a team of technical experts engaged by the Natural Gas
Corporation (previous owners of the Cobb Power Scheme) who were
from Cawthron Institute, Institute of Geological and Nuclear Sciences
(IGNS) and Opus International Consultants Ltd. A large amount of
hydrological, hydrogeological, geochemical and isotopic information
used for the Cobb Dam re-consenting technical reports were sourced
from Council work in the catchment. There were a number of reports
that were produced covering ecology, hydrology and the effects of the
Cobb Dam operation on the water resources of the Takaka Valley
including Te Waikoropupū Springs (TWS). Some of the relevant content
from those reports will be referenced in my evidence.
13. I have been working with Dr Mike Stewart then from IGNS (who is now
retired but consults for GNS and also works under his own company
Aquifer Dynamics Ltd) since the late eighties collecting water quality and
hydrometric and tracer data from the Takaka Catchment. This work
culminated in the publication of a joint journal paper updating all known
hydrological and tracer data and recharge sources to Te Waikoropupū
Springs (Stewart/Thomas 2008).
14. I was the lead author for a resource summary for the Tasman District
Council in 2013 titled: Water Resources of the Takaka Water
Management Area (Thomas/Harvey 2013). This report summarised the
most up to data knowledge of the water resources in the Catchment and
was a base document to the start of the development of a water
management plan for the Catchment.
15. I have read the Code of Conduct for Expert Witnesses in the
Environment Court’s 2014 Practice Note and agree to comply with it. I
confirm that the opinions I have expressed represent my true and
complete professional opinions. The matters addressed by my
evidence are within my field of professional expertise. I have not
omitted to consider material facts known to me that might alter or detract
from the opinions expressed.
Involvement with Te Waikoropupū Springs and Associated Waters
16. Council appointed a Freshwater Land Advisory Group (FLAG) in early
2014 to progress a collaborative process for developing a water
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management plan for the Takaka Catchment. I have attended most of
the FLAG meetings and have provided information and advice on
geology, hydrology (flows and rivers and creeks) and geohydrology
(aquifers and springs) of the Takaka Catchment.
17. I provided relevant hydrological data from Council to Dr Young and Dr
Hay from Cawthron Institute who carried out an ecological flow
assessment for the Takaka Catchment rivers, streams and springs as
part of development of a water management plan for the area. This
information has been used in the Young/Hay Report in relation to setting
water allocation limits, which was undertaken to aid the water
management allocation considerations by FLAG for the catchment.
18. Landcare Research (Mr Fenemor) and Aqualinc Research (Mr Weir)
were involved over this period and carried out various catchment
modelling (flow/quality) to further inform the water management plan
development.
19. I was also involved in more recent work (late 2017) with Dr Stewart on
updating the earlier model from the Stewart/Thomas 2008 paper.
20. I was part of a Science Panel involving a total of eight scientists from
various agencies who were party to preparing a report on the ecosystem
health of Te Waikoropupū Springs, Young et al 2017, Cawthron Report
2949. Dr Young co-ordinated the convening of the panel and
contributions from the various scientists to that report. This report is the
latest published in relation to the ecosystem health of Te Waikoropupū
Springs and considered risk and recommendations in terms of critical
monitoring parameters and included triggers for further action where it
was agreed. This report was principally to support decision making by
the Takaka FLAG specifically in relation to the Te Waikoropupū Springs.
My key contribution to the science panel was the hydrological and
hydrogeological information on the contributing catchments to TWS and
included Council’s long term water quality and flow monitoring from the
TWS. Key aspects of geochemistry, water quality trends, land use
effects, ecotoxicity, and spring ecology and groundwater dependent
ecosystem were addressed in the report by the scientists with
specialised knowledge. Dr Young, Dr Hickey, Dr Stewart, Dr Fenwick
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and Mr Fenemor, who were all involved in the Science Panel, will also
be providing expert evidence for these proceedings.
21. In my reference section I have cited key reports that Council and other
agencies have completed in the Takaka Catchment and are referred to
by other witnesses and I. A dossier of relevant reports will be provided
to the Special Tribunal.
Current Water Clarity Research
22. Council has been involved in a joint research project with NIWA trialling
a deployment in Te Waikoropupū main spring of a device (beam
transmissometer) that uses light to measure transmissance through the
water. The data collected by this device can be used to derive a
measure of water clarity. Another sensor (EXO sonde 2) was co-
deployed with the beam transmissometer to measure a range of other
parameters.
23. The sampling equipment was deployed in the Main Springs from mid-
October 2017 to mid-January 2018. The equipment collected 60
readings every ten minutes resulting in the collection of roughly 750,000
data points for the various parameters. This is a very complex piece of
work given the innovative nature of this project and volume of data
involved. The data has been analysed by NIWA and I have been
provided with a first draft of the findings of the analysis.
24. The Council will be making the information public once the analysis is
completed. NIWA have been asked to have the report finalised by 17
April so it can be made available to the Special Tribunal.
Executive Summary
25. The scope of my evidence covers the most up to date information on the
geology, hydrology and geohydrology of the Takaka catchment relevant
to the Water Conservation Order (WCO) application. I describe the Te
Waikoropupū Springs system including its measured flow characteristics
and outline the areas and water bodies that are relevant to the WCO
application. I also broadly describe the groundwater quality data from
the area and provide information on the status of current allocation and
its impacts.
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26. My overall conclusion in relation to matters covered in my evidence are
as follows.
27. There are three main water bearing units (aquifers) in the catchment
which are described as the Arthur Marble Aquifer, Takaka Limestone
Aquifer and the Takaka Unconfined Gravel Aquifer1. There are complex
interactions/connections between the various aquifers and the rivers
and streams in the area including their recharge and discharge. In some
areas the aquifers are sealed from overlying areas (confined) and in
others they leak and are connected, including to the atmosphere
(unconfined)
28. Te Waikoropupū Springs is a large artesian spring emerging from the
AMA. The TWS includes the Main Spring (which includes Dancing Sand
Springs) with a mean flow of about 10000 l/s and the smaller Fish Creek
including Fish Creek Springs with a mean flow of 3300 l/s. There is also
a component of water discharging to the sea offshore in Golden Bay
~6400 l/s). The smaller Fish Creek Springs regularly goes dry during
extended dry periods of no rainfall and low flows.
29. Not all areas of the Takaka Catchment contribute water to recharging
the AMA, with the amount of recharge to the TWS itself being variable
from the different sources.
30. Alongside biological processes, hydrogeological influences also play a
part in the clarity of water at the Main Spring TWS. These include
filtration through the gravels and marble geology as water passes
through. Settlement of particles in the subterranean systems due to low
velocities and long residence time and also chemical and biological
processes.
31. In relation to the WCO application, the contributing water bodies
(surface and groundwater) to the Arthur Marble Aquifer can be
described as the catchment area upstream of the Waingaro River north
of Hamama (approximately NZTM Map Grid 1582318E 5472726N) and
the catchment area upstream of the Takaka River from about the
Hamama Road turnoff with the Takaka Valley Highway (approximately
NZTM Map Grid 1584078E 5472491N). The other areas that should be
1 Referred to by other witnesses as the AMA, TLA and TUGA.
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included (only groundwater from the Arthur Marble) are areas of the
Arthur Marble geology outliers up the Anatoki River and Pohara and the
confined Arthur Marble Aquifer.
32. Groundwater quality has been regularly (3 monthly) monitored at the
Main Spring TWS from 1990 as part of the National Groundwater
Monitoring Programme and Council’s own State of the Environment
Monitoring (SOE). More recently Friends of Golden Bay have also been
testing the Main Spring TWS (weekly). The level of nitrate-nitrogen is
not static over this time period and has varied within a range from 0.29 –
0.66 mg/L (if outliers are taken out pers. comm. Roger Young and see
Dr Young’s Figure 4). Council has also been monitoring a bore in
Takaka Township in the Takaka Gravel Unconfined Aquifer as part of its
SOE programme. At this site nitrate-nitrogen level has varied between
0.5 – 1.5 mg/L.
33. Comprehensive synoptic groundwater quality surveys conducted by
Council in 2006 and 2016 show the nitrate–nitrogen level as not
changed significantly in the recharge areas around Hamama and the
Takaka Valley.
34. Council monitoring data shows no discernible impact of abstractions
(current allocation is ~540 l/s from the contributing water bodies
described earlier) on TWS. There are also no discernible impacts at
Council’s monitoring bores in the recharge area. By comparison, high
flows during freshes and electricity generation at the Cobb hydroelectric
power scheme have large impacts on groundwater levels in the
recharge area and also at TWS. The impact on flows at TWS is
dampened – due to the nature of the recharge into the AMA.
35. Data used in allocation considerations for the TWS and the main rivers
in the Takaka catchment are measured data. The Cawthron report
(Young/Hay 2017) recommends an ecological sustainable limit of 10 %
of MALF (766 l/s) at the TWS as an allocation limit for the AMA recharge
with a cease take at MALF (7661 l/s). This amount equates to 3.9 % of
overall mean flow in the AMA. If an outflow to sea is added to the MALF
at the main spring the portion of allocation becomes about 7.4 %. From
my hydrological experience these allocations are conservative
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compared to others in the Tasman Region2. Any cease take provision
also further protects the TWS as decline in water flow/pressure can’t be
attributed to abstraction.
Scope of Evidence
36. In the preparation of this evidence I have read:
(a) The Application;
(b) The evidence of the Applicants;
(c) The evidence of Dr Fenwick;
(d) Approved draft evidence of:
i. Dr Roger Young;
ii. Andrew Fenemor;
iii. Dr Chris Hickey; and
iv. Dr Mike Stewart.
37. My evidence will address:
(a) The geology, hydrology and hydrogeology of the Takaka
catchment with specific reference to contributing areas for
recharge to the Arthur Marble Aquifer and TWS. Maps are
included to aid the Tribunal in their consideration of areas that
could be included within the Water Conservation Order in their
deliberations.
(b) The flow characteristics of TWS are explained including effects
of various flow contributions to the TWS. This is to help the
Tribunal understand the flow variability and scale of effects of the
different contributing waters to the TWS and also the potential
impact of abstraction for consumptive use from the contributing
water to the TWS.
(c) Background groundwater quality and variations in the quality
from the monitoring in the Takaka Catchment including at the
TWS are presented. This data will provide a background to the
Tribunal as the status of aquifer water quality in the catchment
2 Motueka-Riwaka Plains allocations are 15% of MALF of the Motueka River above the Plains
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and at TWS. Examples of water quality data from the TWS pre-
irrigation in the main Takaka Valley is also included to provide
context to some of the limits the Applicants’ draft WCO seeks.
The TWS water quality data will be further elaborated by the
other Council expert witness in relation to their analysis and
evidence and provide insight into sources of recharge, water
quality trends and risk.
(d) Current water allocation in the catchment in relation to the AMA
and the impacts of water allocation limits recommended in the
Young/Hay 2017 report on the TWS.
The Takaka Catchment
38. The Applicants have included with their application both the
Stewart/Thomas 2008 paper published in the Hydrology and Earth
Sciences Journal and Thomas/Harvey 2013 Water Resources of the
Takaka Water Management Area report.
39. The Applicants have included Figures 1 to 5 from Thomas/Harvey 2013
with their “Draft” Water Conservation Order. Subject to the addition of a
label “Te Waikoropupū Springs” in Figure 1, the rest of the Figures are
straight out of the Thomas/Harvey 2013 Report. Figures 1 to 5 were for
the purpose of resource description only and not intended for other
uses. This is important because since the release of the
Thomas/Harvey 2013 report, review of hydrogeological information has
resulted in changes to some of the boundaries shown on the figures in
the Application. It is also noted that the Takaka North area in the
Applicants’ Figure 1 is not part of the Takaka catchment itself.
40. Figure 1 below3 shows the Takaka Valley, its main rivers, including the
Takaka River, and TWS which is located in the northwest of the
catchment. The principal river draining the Takaka Valley is the Takaka
River, which flows into Golden Bay. Major tributaries of the Takaka
River include the Cobb, Waingaro, Anatoki and Waikoropupū Rivers.
Figure 2 shows the Takaka Valley River and tributaries and locality
names and is an updated version of one from the Thomas/Harvey 2013
report.
3 Key maps will be supplied by Council for the hearing at A1 size.
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41. The Takaka Catchment is 940 km2 and is of rugged topography with
steep ranges to the east, south and southwest with narrow valleys that
broaden towards Takaka. A significant amount of land (680 km2 or 72
%) in the upper catchments comprises the Kahurangi National Park and
the Takaka Hill Forest Park which are administered by the Department
of Conservation.
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Figure 1 – Takaka Catchment
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Figure 2 – Takaka and Main Valley Rivers and Tributaries
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42. Rainfall is variable throughout the Takaka Valley with high sunshine
hours. Annual rainfall is about 2,000 mm at Takaka township and
increases to around 3,500 mm at Takaka Hill
43. A significant feature in the Takaka Catchment is the Cobb Dam
(Figure 1) which dams the upper Cobb River. The Cobb Dam is a
hydroelectric dam. Its operation significantly affects the flows in the
Takaka River in summer by increasing low flows when generation
occurs. The current 32 MW (megawatt) capacity entails a maximum
generation flow of 7.5 m3/sec (7,500 l/s).
Takaka Catchment Geology
44. The Takaka Catchment comprises rocks of varied and complex geology.
Figure 3 shows a simplified geology of the area within the catchment
with the youngest geology shown at the top of the legend.
45. Figure 4 shows the cross sections at AA and BB from Figure 3. Of note
is section AA, which shows Te Waikoropupū Springs system, which is
within the AMA.
Hydrology and Hydrogeology
46. Hydrological monitoring has been undertaken for many years in the
Takaka catchment going back to the 1980s and earlier. Council has
collected substantial water level and flow information from Te
Waikoropupū Springs (including Fish Creek) since the mid-1990s.
There is also a flow monitoring network for the major rivers and the
groundwater in the catchment (Figure 5). The data from all the
monitoring sites combined with more specific localised monitoring (e.g.
concurrent low flow river measurements and bore water level checks)
provide a good level of information for the Council to understand the
characteristics of flows and water level changes in the rivers and
aquifers of the catchment including TWS and within the AMA.
47. A key metric used in hydrological data presentation and in setting
allocation limits and flow management regimes (e.g. minimum flow) is
the 7-day Mean Annual Low Flow (MALF). Other metrics normally
included are flows (re: low flows) for different return periods e.g. 1:5 yr.
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and 1:10 year. Dr Young/Hay from Cawthron were supplied all the
relevant flow data for the Takaka Catchment by the Council for their
assessment of ecological flow setting. This data was used by them in
the Young/Hay 2017 report.
Figure 3 – Takaka Geology Map
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Figure 4 – Geology Cross Sections
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Figure 5 – Water Resource Monitoring Sites – Takaka Catchment
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48. The 7-day MALF is based on the total historic flow record held for each
river, and is the average of the lowest running 7-day average flows in
each hydrological year of the historic record. The 7-day MALF is the
common metric used by the Tasman District Council in its regional flow
assessments.
49. For completeness of hydrological flow information, I have included maps
of individual catchments principally of the Takaka (both Upper and
Lower Takaka Valley around Takaka Township), Waingaro, Anatoki,
and Motupipi with the relevant flow statistics in Appendix 1 to 5 with
Appendix 9 listing the data time ranges for the flow statistics.
50. There are significant groundwater resources underlying the Takaka
Catchment comprising three main water bearing units (i.e. aquifers).
These units are directly related to lithology (rock characteristics) and
geology. The three main aquifers in the catchment are the Arthur Marble
Aquifer, Takaka Limestone Aquifer and the Takaka Unconfined Gravel
Aquifer. There are complex interactions/connections between the
various aquifers and the rivers and streams in the area including their
recharge and discharge, and their nature i.e. unconfined and confined4.
Limited and localised groundwater may occur in some areas especially
in the coastal deposits and aggradational terraces shown in Figure 3.
51. The distinctive feature of the AMA is the karstic, or karst landscape.
This surface and subsurface landscape is shaped by the dissolving
action of water on carbonate rock (marble) in the area. Rain gathers
carbon dioxide (CO2) as it falls. It picks up more CO2 when it hits the
ground and forms a weak solution of carbonic acid. Over long periods
this dissolves the carbonate rocks leaving interesting and unusual
features, including cave systems, sink holes, disappearing streams and
springs. The evolution of the karst landscape including the
subterranean one is a natural and ongoing process.
52. The Arthur Marble geology outcrops over a large part of the Catchment
and underlies the Takaka Valley (as shown by Figures 3 & 4). The
4 Unconfined Aquifer is one where the permeable rock units are open to receive water from the surface i.e. in direct contact with the atmosphere. Confined Aquifer is one where the permeable rock units are overlain by impermeable rock.
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sheer size and the nature of the dissolution of the marble make it a
complex system.
53. The marble’s thickness is variable over the Catchment, but is thought to
be at least 500 m and possibly 1000 m in vertical thickness. The cross-
sections at Figure 4 give an indication of the size and thickness of the
Arthur Marble. Estimates of storage in the marble system are about 3.4
km3, which is 3,400 billion litres.
54. The AMA is an unconfined aquifer in its southern parts. To its north, as
it extends into Golden Bay it is a confined aquifer. Figure 6 shows the
latest updated information of the extent of the Arthur Marble Geology
and the extent of the Unconfined and Confined parts of the AMA. I
would like to highlight to the Tribunal that there has been some
refinement to the confined/unconfined boundary in this map (around the
Hamama area) compared to that in Thomas/Harvey 2013. This has
been due to more drilling information obtained from this area. More
descriptive locational details including of the confined/unconfined aquifer
extent in the catchment is provided in Thomas/Harvey 2013 pp19-21.
55. The unconfined part of the AMA is where the surface water flows
directly into the aquifer through surface gravels or the exposed marble
geology. In the confined part of the aquifer surface water does not flow
into the aquifer because of an impermeable layer of rock (usually
mudstone and silt stones known as the Motupipi Coal Measures) that
sits above the permeable rock (the Arthur Marble) the water within the
aquifer flows through.
56. Many of the creeks in the area (above the unconfined AMA) flow in their
upper reaches but upon reaching the underlying marble geology go dry.
The Takaka River loses on average 8,000 l/s through the gravel of its
riverbed into the karst aquifer system. Other flow contributions (other
rivers, karst hills and valley input) to the recharge of the AMA would be,
on average, in the order of 11,000 l/s. Thomas/Harvey 2013 pp 8-10 &
pp 23 provides the flow loss ranges and source contributions.
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Figure 6 – Arthur Marble Aquifer, Confined & Unconfined Extents
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57. The Takaka River regularly goes dry downstream of Lindsay’s Bridge
(Figure 2). This drying phenomenon is not new and there is recorded
data on this from the late 1800’s. The drying of the Takaka River
migrates upstream from the area around where the East Takaka
Springs (Figure 2) enters the Takaka River to just below the Ironstone
Creek confluence with the Takaka River at Sparrows.
58. The lower end of the Takaka River drying section can be anticipated to
be dry when the flows at Harwood’s (Figure 2) drop below 7000 l/s, with
the upper end being dry when flows drop below 3500 l/s. During low
groundwater levels drying at the lower end could happen when flows are
much higher at Harwood’s (i.e. 15,000 - 20,000 l/s). Resource
information and studies as part of the Cobb Dam permit renewals
concluded that the historical operation of the Cobb Dam has increased
the natural flows in the Takaka River (for low to medium flows), and also
reduced the amount of time the Takaka River would naturally be dry
below Lindsay’s Bridge (Waugh et al 2000).
59. The Takaka River downstream of the East Takaka Springs lies above
the confined AMA. The East Takaka Spring (limestone geology sourced)
flow supplements the river flow below this location to Payne’s Ford.
Below Payne’s Ford the Waingaro, Anatoki and Te Waikoropupū Rivers
are the major rivers that flow into the Takaka River. The flows in the
Takaka River below the East Takaka Springs do not contribute water to
the AMA as the AMA is confined. Flow statistics for the Takaka River in
its flowing reaches in the upstream and downstream location are
provided in Appendix 4 and 1.
60. The losses from the Takaka River in the reaches above East Takaka
Springs is one source of recharge to the underlying unconfined gravel
aquifer and AMA in the unconfined parts.
61. In paragraph 58, I mentioned the Cobb Dam and its effects on the
Takaka River flow. Work done for the Cobb Scheme (White et al 2001)
provided information on effects of various water bodies on groundwater
in the catchment including the TWS. The report in pp 4-17 says
“Discharges from Cobb dam are shown to cause changes at Pupu
Springs flow when flow at Harwood’s is less than 10,500 l/s. The
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relationship between change of steady-state discharge of the Cobb Dam
and change of Pupu Springs discharge is: Pupu Spring flow change (l/s)
= 0.6 x Cobb Station discharge change – 300 l/s”.
62. Mr Fenemor has carried out more recent modelling work involving both
hydrology and groundwater quality with Aqualinc Research Limited in
the Takaka catchment and he discusses that in his evidence.
63. Parts of the Waingaro River from its mid reaches north of Hamama
(Figure 1) is underlain by alluvial gravels which in turn overlay the
unconfined AMA. White et al 2001 quoted in paragraph 61 also provides
information on the possible contribution from the Waingaro River to
TWS. In pp 3-13 the reports says from the analysis of flow events “that
the Pupu Springs flow response to Waingaro River flow event is 6+/-6 %
of the flow in the Waingaro River.” The report further says “it’s uncertain
whether the relationship above can be applied to average Waingaro
flows”.
64. Based on concurrent flow measurement data along the Waingaro River
during low flows we can also assess the flow losses in the unconfined
reach to the TWS. The flow losses during low flow measurements
observed ranges between 500 - 1000 l/s. Stewart Thomas 2008 notes
the Waingaro contribution to be about 2000 l/s for mean flows at TWS.
The highest losses are about 10 % of the mean TWS flow reported in
Stewart/Thomas 2008.
65. The area below the mid-reach of the Waingaro is underlain by
impermeable Motupipi Coal Measures geology that caps the marble.
Any river flow losses here will be going to the underlying gravel aquifer
and not the AMA as this impermeable layer prevents overlying recharge
from entering the AMA. The impermeable layer extends out towards
TWS and past the Anatoki River and Takaka Township and eastwards
towards Pohara (Figure 1). Drilling data and geological mapping work is
the basis of delineation of the extent of this impermeable confining layer.
66. The Anatoki River has a small section of Arthur Marble Geology in the
mid-section of its upper reaches. Analysis of flow data from river flushes
here do not show any responses at the TWS. The geological data
available also shows the Anatoki River from its mid reaches and
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downstream is capped by a confining layer of Motupipi Coal Measures
geology. From a hydrological perspective the surface water flows from
the Anatoki River are not connected to TWS.
67. Turning to the Takaka township, the limestone geology underlying parts
of it extends from about the Fonterra Plant where the limestone
outcrops. The limestone geology extends underground below the
Motupipi River and eastwards to Pohara and Clifton (Figure 1) where it
outcrops again at the surface. In these areas the limestone geology is
underlain by the impermeable Motupipi Coal Measures geology. So
while the limestone geology has groundwater in it (albeit limited), in the
areas described above there is no contribution to the AMA.
68. The Waikoropupū River Catchment and its surface water from the
various streams that feed it and the shallow groundwater in the valley do
not contribute to the AMA recharge. The TWS emerges in the lower
Valley floor of the Waikoropupū Catchment having breached the
capping Motupipi Coal measures geology here. Geological data from
drilling shows the capping layer of the Motupipi Coal Measure is thin (10
m) just upstream of the main spring TWS compared with further up the
valley where thickness is over 30 m.
69. The WCO application by its construct would apply to the whole Takaka
Catchment. The geohydrological information detailed in my evidence
here and that of other published and available information quoted in my
evidence does not support this. Having considered all the available
geohydrological information, it is my professional opinion that the WCO
Application seeks to include areas that have no hydrological connection
and do not contribute to the recharge of TWS.
70. To aid the Tribunal, I have produced a map at Figure 7. This figure
outlines the attributable recharge areas and includes both the
unconfined and confined marble geology. The marble geology is
exposed in many parts of the catchment. To account for the marble
outcrop outliers in Pohara and up valley in the Anatoki (Figure 6) I have
added these areas to the confined AMA. In these areas only drilled
bores extracting groundwater from the AMA geology need to be
considered as part of any allocation from the AMA. All other surface
455328\247\ 23
water and groundwater does not have a hydrological connection to the
AMA.
Figure 7 – Attributable Zones to the Arthur Marble Aquifer (AMA)
455328\247\ 24
71. In the case of the Anatoki there are no river flow loss effects on the
TWS. There is some marble geology outcropping in the mid Anatoki
reach which is mainly in the Kahurangi National Park with some marble
being adjacent the Happi Sam Society Incorporated land at the end of
McCallum Road (which goes up the Anatoki Valley). By recommending
the inclusion of this marble geology area into the WCO, I have taken a
conservative approach because it contemplates any proposals to drill
deep bores into the Arthur Marble Geology here. This approach
addresses any issues of connectivity off the Arthur Marble Geology here
to that underlining the Takaka Valley.
72. In the case of the exposed marble geology in the Pohara/Clifton area,
surface water is limited and many of the streams in parts of the marble
geology don’t flow. Similar to the Anatoki, by including the marble
geology here it addresses any proposals to drill deep bores into the
Arthur Marble Geology. Taking this approach to the exposed marble
geology would account for all the areas related to the marble (confined
and unconfined) geology.
Te Waikoropupū Springs Setting and Flow Characteristics
73. TWS is a large karst resurgence (i.e. it’s an artesian spring) consisting
of a main spring (including Dancing Sands Spring) with a mean
discharge of 10,000 l/s, and a number of smaller springs known as Fish
Creek Spring. These flow into Fish Creek which has a mean discharge
of 3,300 l/s (Stewart/Thomas 2008). Figure 8 shows a schematic map
layout of the various springs within TWS area as it is now. Figure 9
provides an aerial picture of the spring’s area with the boundary of the
Department of Conservation (Doc) Reserve. Physically all of TWS
springs area is within the Department of Conservation Scenic Reserve.
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Figure 8 – Schematic Map of Te Waikoropupū Springs
455328\247\ 26
Figure 9 – Te Waikoropupū Springs Aerial Map
455328\247\ 27
74. The emergent water from the TWS is groundwater and typically
groundwater has different characteristics from surface water. The
characteristics of groundwater depend on recharge sources, geology of
pathway the water travels, including its residence time. Groundwater
dissolves minerals from the geological material it travels through. As
water is below ground it is also less oxygenated compared with river
water because any uptake of oxygen through organic matter breakdown
processes is not replaced by reaeration from the atmosphere. Natural
chemical processes can also occur in groundwater due to its oxygen
content or lack of.
75. One of the factors that contribute to the clarity of the water at TWS is the
hydrogeological influence. These relate to removal of particulate
material by filtration through the gravels overlying the AMA and gravels
underlying the rivers/streams that contribute to the AMA. Filtration within
the marble geology where conduits have sand and gravel infill will occur,
especially at the entrance to these conduits. The relatively long
residence times between recharge and re-emergence at the main
springs and slow velocities within the large aquifer system aids
settlement of fine particles. Further the lack of fine grained sediment in
the aquifer and its slow velocities reduces any generation of fine
particles by abrasion. Biogeochemical process would also be a
contributor to clarity in relation to effects on humic material entering the
system eg chemical adsorption and biological effects.
76. In relation to the WCO application, the contributing water bodies
(surface and groundwater) to the Arthur Marble Aquifer can be
described as the catchment area upstream of the Waingaro River north
of Hamama (approximately NZTM Map Grid 1582318E 5472726N) and
the catchment area upstream of the Takaka River from about the
Hamama Road turnoff with the Takaka Valley Highway (approximately
NZTM Map Grid 1584078E 5472491N). The other areas that contribute
are areas of the Arthur Marble geology outliers in the Anatoki River, at
Pohara and the confined Arthur Marble Aquifer. The areas described
above are shown in Figure 7.
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77. Fish Creek Springs drain into Fish Creek, which has a catchment that
extends behind the springs. Hence Fish Creek water has a component
of surface water. During base flows this input is about 50 – 100 l/s and
during heavy rain periods surface flows can exceed 10,000 l/s. Careful
distinction needs to be made when parties refer to Fish Creek – re:
whether it is the Fish Creek Springs or Fish Creek.
78. Fish Creek Springs regularly goes dry during extended drought periods.
As an example it was dry before Christmas 2017 as water samples were
not able to be collected then. This drying phenomenon of Fish Creek
Springs has been observed for many years by me personally on my
visits. Fish Creek also goes dry above the Fish Creek Springs during dry
periods.
79. The main spring (including Dancing Sand Springs) does not have any
surface catchment that flows into it. The main spring flow enters Fish
Creek downstream of the Salmon Farm intake and then the surface
stream is known as Springs River (Figure 8 and 9). Springs River
subsequently flows into the Te Waikoropupū River below the Salmon
Farm discharge.
80. A natural hydrological phenomenon is that during extreme rain events
(which do occur in Takaka) the whole of the lower Te Waikoropupū
Valley can flood and overland flow can also enter the main spring. From
my personal observation over the years during heavy rain there is also
overland flow from within the DOC scenic reserve into the main spring.
This is natural drainage but needs to borne in mind when physical and
chemical measurement data are considered.
81. In 1999 Council installed a groundwater bore (bore WWD 6013 – see
Figure 8) into the AMA adjacent to the Main Spring to monitor water
levels. As such continuous water level data has been available since
that time. The levels from the bore have been cross correlated to
measured flows in Fish Creek/Springs River and the salmon farm to get
a relationship to derive actual main spring flows. Council also has a
measurement device at Fish Creek (Figure 8) and measurements from
the salmon farm have been undertaken as part of their resource consent
requirement since the farms inception in the 1980s.
455328\247\ 29
82. The TWS are the main discharge area for the AMA, which underlies
much of the Takaka Valley and outcropping (Arthur Marble geology) to
the east and west as shown in the geology map (Figure 3).
83. Hydrogeological and water balance studies show that water from the
AMA also discharges out to Golden Bay. Dr Stewart and Mr Fenemor in
their evidence provide information on these off-shore discharges. Dr
Stewart also comments on the chloride levels in the spring water and
their attribution to seawater source and how they enter the springs.
Some information on this is also available within the Thomas/Harvey
2013 pp 22-25.
84. There is no proof to date of any discreet offshore springs bubbling out in
Golden Bay, even though numerous comments have been made about
their presence. Several investigations to locate these offshore springs
have been unsuccessful. Hydraulic and hydrogeological information
suggest that water from the AMA is likely diffusing out in the bay over a
wide area and hence not obvious.
85. The bore WWD 6013 (Figure 8) shows larger responses when river
flows are high, with concurrent rainfall reflecting recharge into the
marble. This is important because it confirms river flow and rainfall
recharge are big influences on the flow within the AMA.
86. One of the observations from bore WWD 6013 (20 m deep) is that the
bore has always been artesian. Figure 10 shows that the water level has
been above ground level since installation in 1999. This positive head
has occurred even during drought periods and when generation flows
from Cobb have been low or even stopped. There is about 10 m of
capping geology (Motupipi Coal Measure) here before Arthur Marble
geology is encountered. This shows that the confined marble geology is
always hydrated (wet) here. This is supported by data from another bore
(WWD 6011) up Te Waikoropupū valley.
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Figure 10: Water levels above mean sea level at WWD 6013 - TWS
87. Monitoring bores in the unconfined part of the marble in the Takaka
valley floor show large water level fluctuations – these large variations
are due to elevation, low river flows and Cobb Dam generation
(Thomas/Harvey 2013 pp21). My observation of levels from Council
bores in the Takaka Valley floor still show that the largest fluctuations
are within the overlying unconfined gravel aquifer. This shows the
deeper underlying unconfined AMA is always hydrated (wet).
88. The Cobb Dam has an effect on river flow and recharge that is more
obvious during the summer months when river flows are lower. When
the Cobb Dam’s peak discharge of about 7500 l/s is substantially
reduced or shut down, water level and flow reduction is observed at Fish
Creek Springs and Te Waikoropupū Springs. This demonstrates that it
is large inputs that show a measurable effect at the springs.
89. Council has been closely checking for any measurable effects of
abstraction on the TWS using the available water usage data and flows
measured at the TWS. We (Council hydrology staff including me) have
been unable to see any discernible effects of abstraction. As an
example (Appendix 8) we looked at a dry period over the summer of
2015/2016. Even at the peak abstraction period (from the largest
455328\247\ 31
permits peak week rate of 318 l/s) in the recharge area we could not see
any discernible effects at the springs. It is the larger hydrological effects
mentioned in paragraphs 87 and 88 that dominate effects at the springs.
We have similarly looked at various other dry periods and have come to
the same conclusion.
90. The generation pattern of the Cobb Dam has changed due to electricity
market changes in the late 1990s. What has been observed is the
average Takaka River flow (affected by the Cobb Dam) is lower now in
spring and summer, and higher in winter. The probable cause is under
the old regime more water was stored in winter and more released in
summer. Now I understand generation is more evenly spread
throughout the year.
91. Figure 11 shows the annual average flow at Te Waikoropupū main
springs since 1991. This is an updated plot to that in Thomas/Harvey
2013. Overall there is more flow in the wetter years. The average flows
over the 26 years have been between about 8.9 m3/sec to 10.8 m3/sec.
This shows that there is natural variability in the flows from year to year
but overall the flows are substantial (ie mean flow of 10m3/s). The main
spring TWS has never been known to go dry.
F
Figure 11 – Average Flows at Te Waikoropupū Main Spring
455328\247\ 32
92. Figure 12 shows the actual instantaneous flow measured at the main
springs since 1999. The lows correspond with periods of drought and
low Cobb generation. Even in the 2001 drought which was a severe
drought (50 yr. drought - 2 % chance of occurring in any given year)
there was still 5800 l/s of water discharged from the main springs.
Figure 12 – Instantaneous Flows at Te Waikoropupū Main Spring
93. Figure 13 shows the flow statistics for Te Waikoropupū main spring and
Fish Creek and other associated streams within the Te Waikoropupū
Catchment. The data in relation to MALF at the main spring (i.e. 7661
l/s) is what Dr Young/Hay 2016 considered in their recommendation on
sustainable ecological flow setting. This data presented here is further
revised and updated from those in the Thomas/Harvey 2013 report.
455328\247\ 33
Figure 13 – Te Waikoropupū Zone and Flow Statistics
Groundwater Quality – Takaka Catchment & Te Waikoropupū Springs
94. Co-ordinated long term monitoring of groundwater started in the Takaka
catchment from about 1990. There was also earlier groundwater quality
testing noted in Thomas/Harvey 2013 references.
95. More specifically to the main spring Te Waikoropupū Springs three
monthly sampling and testing was started from 1990 as part of the
National Groundwater Monitoring Programme (NGMP). Council has
been collecting the samples with the analysis carried out by the Institute
of Geological and Nuclear Sciences (IGNS, now GNS). This programme
is still ongoing with GNS.
96. Council has also been monitoring groundwater quality from the Takaka
Gravel Aquifer (from 2000) and a bore within the Takaka Limestone
Aquifer (from 1990) within the Takaka Catchment.
97. To complement the three monthly monitoring Council also carried out
synoptic (snapshot) survey’s involving several bores/wells in the
catchment in 2006 and 2016. Most of the bores sampled are in the
Takaka Gravel Aquifer both over the unconfined and confined AMA.
There are only a limited number of bores both in the Takaka Limestone
455328\247\ 34
and the AMA, this is primarily due to the cost and risk of drilling to depth
to access water in these geologies.
98. Council has also collected more specific samples from various sources
in the catchment for information that went to aid the Cawthron Science
Panel Report 2949. Quarterly sampling has also been commenced
from the Takaka River at Lindsay’s Bridge and Fish Creek Springs
(where the past isotopic samples were collected) over the last two
years. More recent (late 2017) isotopic and chemical sampling work has
been also undertaken with Dr Stewart. Dr Stewart will cover those in his
evidence.
99. As stated above, Friends of Golden Bay (FGBA) have also been
collecting weekly water samples from February 2016 at the Main
Springs (same site as Council), Fish Creek Spring (a different spring to
TDC’s) and Fish Creek upstream of Fish Creek Springs at the boundary
of the DOC Reserve and the adjacent land. Council has aided this
sampling with showing FGBA the groundwater sampling protocols and
techniques when they started and has loaned field testing instruments to
the FGBA.
100. Having monitored the TWS and collected water samples from the main
springs since 1990 I have noticed variations in the nitrate – nitrogen
content. The levels are not static but show variations over time. The
measured range for nitrate-nitrogen for the data collated to date
excluding outliers is in the range from 0.29 to 0.66 mg/LN (Dr Roger
Young pers. Comm.).
101. Appendix 6 contains the analytical results from samples that were
collected using a diver at TWS in June 1999. Samples were collected
from the five vents in the main spring, a sample from Dancing Sands
Springs (Appendix 7) and a sample from bore WWD 6013 (Figure 8).
The nitrate-nitrogen levels from 4 vents, Dancing Sand Springs and the
bore were all 0.46 mg/L with one other vent in the main spring showing
a value at 0.47 mg/L. When this sampling was done there was no dairy
irrigation in the Takaka Valley above Spring Brook (Figure 2). I consider
this as useful snapshot information in the context of other data that has
been presented.
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102. Most groundwater is abstracted from the Takaka Gravel Aquifer. All of
Takaka Township has private bores and I have personal experience of
the locals telling me they have pride in “their excellent groundwater
quality”. Sampling (3 monthly) from 2000 indicate nitrate levels in the
township aquifer (Takaka Gravel Unconfined Aquifer) varying from 0.5
to 1.5 mg/L. The aquifers underlying the Takaka Valley in other parts of
the catchment also show variations.
103. Figure 14 shows the synoptic data from the 2006 and 2016 surveys. At
a catchment overview scale, the nitrate levels in the unconfined parts of
the AMA i.e. the gravel aquifer, has not changed significantly. The AMA
and limestone aquifer are limited by the availability of sampling sites.
104. Groundwater quality at TWS main spring site has been monitored for
many years and there is a large amount of data, which is discussed in
Dr Young and Dr Hickey’s evidence.
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Figure 14 – Takaka Groundwater Surveys
455328\247\ 37
Water Allocation Impacts and Current Allocations/Use Impacts
105. In his evidence, Dr Young recommends 10% of the 7 day MALF (at the
main spring TWS) which is 766 l/s as a sustainable allocation limit for
the AMA recharge and Te Waikoropupū Springs. The minimum flow
specified is 6895 l/s with a cease take of 7661 l/s (7 day MALF) at the
main spring.
106. From a water management perspective cease take provision means that
abstraction impacts will not affect the resource decline (flow/level).
However it is natural in all water systems for flows/levels to decline if low
flows/droughts continue until recharge from rainfall and higher river
flows raises flows above the cease threshold. As an example of flow
variability Figure 11 & 12 shows the annual and instantaneous flow
variations at the main spring.
107. Figure 12 shows the large natural variability in flows at the TWS and as I
have explained in earlier paragraph 89 any impact of abstraction is not
discernible. Further water level fluctuation in the unconfined AMA as
described in Thomas/Harvey 2013 also shows large variations (up to
about 28 m) in the aquifer water levels. These are mainly due to
elevation, low river flows and Cobb generation. At the scale of the
natural and Cobb induced water level variations observed at these
bores it is not possible to discern any current abstractive effects on
water levels and consequently flows at TWS. Further any velocity
changes to flow within the marble due to any abstractive effect would
also be undetectable considering these other larger variations. In my
opinion this would also be the case if the abstractive effect of the
Young/Hay recommendation for allocation at the TWS is considered.
108. In the Takaka Catchment there are currently only three permits out of 29
related to the AMA recharge zone (all takes from the Takaka River)
which have cease take requirements resulting from Commissioner
hearings in the early 2000s.
109. The three permits above (~240 l/s) have been metered from when they
were exercised and provide a useful insight to water use. I have looked
at their use and all have at some point used their full allocation. The key
considerations in assessing water permits at Tasman is the soil type,
455328\247\ 38
use of the water, water use efficiency and avoidance of leaching. Only
the needed allocations of water justified is allocated for irrigation.
110. Actual water use will vary in the catchment and will depend on the crop,
climatic factors (rainfall/soil moisture/irrigation rotation) and timing in the
season, in reality the peak weekly allocations are not always hit except
in dry weeks.
111. The National Regulation on water metering 2010 is bringing on board
new water usage data but depending on the flow band (the last band re:
5 – 10 l/s) meter verifications for the last set were only required by mid-
2017. Over time more water usage data will become available.
112. The Young/Hay 2017 report provides recommendations for allocation
setting on all the other major surface water bodies in the Freshwater
Management Zones for the Takaka Water Management Area. This area
includes the Takaka Catchment and catchments to the north of Takaka
and includes areas up to the Wainui Catchment east of Takaka.
113. Both Dr Stewart and Mr Fenemor in their respective evidence have
calculated mass balance of flows through the AMA system. Both
analysis shows that the overall flows outflowing though the AMA is more
than that measured at both the main spring and fish creek spring. Both
analysis indicates a third component of water which is flowing out likely
into Golden Bay. Dr Stewart’s calculations indicate about 33% of the
mean flow flows out to the Bay.
114. Both Dr Stewart’s and Mr Fenemor’ s calculation show an overall mean
flow of about 19750 l/s through the AMA. From a comparative point the
allocation discussed by Dr Young of 766 l/s is 3.9 % of that mean flow.
115. I have taken a simplistic approach and assumed if at the 7 day MALF at
the main spring there is a further 33 % of water flowing out to sea and
not considering any Fisk Creek flow. The total outflow would be about
10320 l/s. In this case a 766 l/s allocation is about 7.4 % of that flow.
The above estimates show in a simple way that the variations in
proportions are dependent on what flows they are compared to.
116. The current total allocation in the areas related to the AMA confined and
455328\247\ 39
unconfined is 540 l/s. Of the above allocation there is only one permit
(for 6.7 l/s) current at the time of writing of this evidence that is in the
confined AMA. Figure 15 shows the location of permits related to the
AMA.
117. Not all water bodies in the attributable zones to the AMA (Figure 7)
contribute evenly to the TWS. Specific details as to allocating water
from the different water bodies (surface and groundwater contributing to
AMA and TWS recharge) with their differing contributions to TWS and
different localised effects on surface and groundwater requires detailed
examination.
455328\247\ 40
Figure 15 – Current Water Take Consents (March 2018)
455328\247\ 41
Comments on Expert Evidence from the Applicants
Emeritus Professor Williams’ Evidence:
118. I agree with the general description of the geology and aquifers in the
Takaka catchment as contained in Prof Williams evidence. I note that
Prof Williams refers to Stewart/Thomas 2008 in several sections of his
evidence both referenced and unreferenced.
119. Prof Williams uses hydrological statistics for flow referenced to Tasman
District Council. Hydrological statistics change over time as more data
becomes available or historic ratings are altered. So while the numbers
may not be wrong, there may be differences in flow statistics presented
by Prof Williams compared to that of my evidence, as I have used more
recent data although I believe they are not significant. For this reason I
have referenced the duration of hydrological statistics I have used in my
evidence (Appendix 9).
120. Prof Williams broadly describes the recharge areas to the AMA in his
evidence at paragraphs 35 and 36. Prof Williams also explains the
confined unconfined parts of the AMA. Prof Williams quotes Figure 1 in
paragraph 35 as the area contributing flow to the AMA and hence TWS.
Prof Williams acknowledges in paragraph 36 the boundaries depicted in
Figure 1 of the confined aquifer need to be interpreted with care.
121. In my opinion Figure 1 in Prof Williams' evidence is inaccurate and may
be based on older data. I have constructed a map based on the most
recent data including from bore logs and also using information post
Thomas/Harvey 2013. Figure 7 in my evidence better reflects the
attributable areas contributing flow to the AMA and TWS. Prof Williams
excludes the exposed Arthur Marble geology in the Anatoki Catchment
and areas north of Rameka Creek heading towards Pohara. I have
included these in my map but only in relation to any groundwater
abstraction from within the Arthur Marble here. I have also included
areas of the confined AMA again only in relation to groundwater from
the Arthur Marble Aquifer in my map. I consider my approach is more
conservative.
122. I agree with Prof Williams in paragraph 11, 77 and 80 that only
contributing areas to recharge (quantity/quality) affects TWS. In relation
455328\247\ 42
to quantity effects I have explained in my evidence that only large
changes in flow/rainfall (flood and freshes) and Cobb generation during
drier periods show measurable effects at the TWS.
Dr Fenwick’s evidence:
123. In relation to information in paragraph 67 of Dr Fenwick’s evidence, in
which I have been quoted, some of the text appears to have been lost or
mixed up. For clarification, Dr Fenwick approached me and provided
two locations of the bore sites quoted and enquired where and what
aquifer the bores where from.
124. I responded to Dr Fenwick via an email stating that the locations were
on the Unconfined Takaka Gravel Aquifer (off Kotinga Road and the Old
Globe Hotel Corner). I provided aerial photos with the location to him. I
commented to Dr Fenwick that I believed both would have been shallow
wells/bores as there would not have been many drilled wells over this
area at that time as water is easy to access (~5 m or so) at shallow
depths. I also commented that both locations were over an area where
the Arthur Marble Aquifer is confined and from a geology viewpoint this
is essentially the alluvial gravels from which most of the Takaka
Township taps water from.
J T Thomas
6 April 2018
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References
Stewart M K, Thomas J T. 2008. A conceptual model of flow to the Waikoropupū Springs, NW Nelson, New Zealand, based on hydrometric and tracer (18O, Cl, 2H and CFC) evidence. Hydrology and Earth System Sciences 12, 1-19, 2008. Thomas J T, Harvey M.M. 2013. Water Resources of the Takaka Water Management Area. Tasman District Council Resource Report Waugh J R, Su-Wuen O., Payne D.A., Harding S.J. 2000. Takaka Catchment River Flows 1945-1999 – Opus International Consultants ltd., Prepared for Transalta May 2000. White P A., Cameron S., Hong T, Read S L A, Stewart M K 2001. Hydrogeology of the Takaka River Catchment and assessment of the effects of the Cobb Power Station operation on groundwater in the Catchment – Institute of Geological and Nuclear Sciences Client (IGNS) Report 2000/41 March 2001. Young R, Hay J. 2017. A framework For Setting Water Allocation Limits and Minimum Flows for the Takaka Water Management Area, and An Assessment of the Geological Contribution of Nitrogen Load to Te Waikoropupū. Cawthron Report 2977 January 2017. Young R, Fenwick G, Fenemor A, Moreau M, Thomas J, McBride G, Stark J, Hickey C, Newton M 2017. Ecosystem health of Te Waikoropupū. Prepared to support decision making by the Takaka Freshwater Land Advisory Group. Cawthron Report No. 2949 March 2017.
44
Appendices
Appendix 1
45
Appendix 2
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Appendix 3
47
Appendix 4
48
Appendix 5
49
Appendix 6 – Analytical Results, TWS June 1999
50
Appendix 6 continued…
51
Appendix 7
455328\247\ 52
Appendix 8
53
Appendix 9 – Flow Site Statistics Data Time Ranges
Flow Site Data Time Range
Anatoki at Happy Sams Aug-1987 to Apr-2015
Fish Creek at Waikoropupū Springs Apr-1985 to Jul-2013
GW 6013 - Te Waikoropupū Main Spring Aug-1999 to Jul-2015
Motupipi at Reillys Br Nov-2006 to Oct-2012
Takaka at Harwoods Aug-1975 to Jul-2013
Takaka at Kotinga Aug-1986 to Apr-2015
Waingaro at Hanging Rock Aug-1986 to Apr-2015