A SUSTAINABLE REBUILT CITY USING GEOTHERMAL HEAT

Proceedings 39th New Zealand Geothermal Workshop

22 - 24 November 2017

Rotorua, New Zealand

A SUSTAINABLE REBUILT CITY USING GEOTHERMAL HEAT PUMPS:

THE CHRISTCHURCH STORY

Anya Seward

, Brian Carey

, Zeb Etheridge

, Melissa Climo

and Helen Rutter

GNS Science, Private Bag 2000, Taupo 2000

Environment Canterbury, PO Box 345, Christchurch 8140

3 University of Canterbury, Private Bag 4800, Christchurch 8140

Aqualinc Research Limited, PO Box 20462, Christchurch 8543

a.seward@gns.cri.nz

Keywords: Geothermal heat pumps, Christchurch, aquifer

heating.

ABSTRACT

The post-earthquake re-build of Christchurch’s inner city has

allowed large commercial-scale building owners to design

and utilise more efficient building energy systems using

aquifer based geothermal heat pump (GHP) technology. The

city is located on a series of confined aquifers, ranging in

depths from 5 m to greater than 200 m. These aquifers

contain water that is consistently between 12-13

C providing

a stable consistent source of heat energy. The systems extract

heat from this source and also use it as a sink for cooling.

The overall annual energy requirements from a large

commercial building will usually require a greater cooling

load than heating load. Six years after the earthquakes, there

are over fifteen large GHP projects under-development or

completed across the city and this paper summarises these

GHP developments with a view to showcasing the present

use of this technology in New Zealand.

1. INTRODUCTION

Geothermal heat-pumps (also known as ground-source heat

pumps or geoexchange systems) harness low-temperature

renewable energy stored in shallow near-surface soils, rocks

and ground water at a relatively constant temperature for heat

supply and also as a heat sink when cooling is required. The

heat transferred from the subsurface is upgraded into useable

energy using mechanical compression plant that changes the

temperature of the energy supplied. In the Christchurch

circumstance the aquifer waters are at a temperature such

that free cooling is able to be used which enables energy to

be transferred to the aquifer water without requiring the use

of mechanical compression equipment. These systems are

highly effective in using a renewable energy source for

heating and cooling larger commercial facilities.

Geothermal heat pump (GHP) systems are used extensively

in Europe where they are a common technology (Weber et

al, 2014; Lind, 2011). The uptake of this technology in New

Zealand is more recent, with approximately 150 known

installations throughout of the country (Carey et al, 2015).

Most of these installations are located in the South Island,

with only a handful located in the North (GNS Geothermal

Use database - 2017). Facilities with greater heating and

cooling demand, such as airports, libraries, swimming pools,

hospitals, convention centers and larger accommodation

facilities (e.g. hotels, lodges, residential care) are adopting

aquifer-based GHP technology when the circumstances are

right. Christchurch is particularly suitable as is discussed in

this paper.

New Zealand’s climate is generally temperate, experiencing

neither excessive heat nor extreme cold. In the residential

home sector this has led to a history of minimal investment

in home energy systems with the population generally having

lower expectations of indoor comfort than is found in many

other nations (Climo et al, 2012). This is a barrier to the

uptake and utilisation of GHP technology in this sector

(Coyle, 2014) where these types of systems are really only

being installed in top end residential circumstances.

2. CHRISTCHURCH

Christchurch city, Canterbury, has had the greatest recent

growth of GHP technology in New Zealand. The key driver

for this has been the rebuilding of a greener more energy

efficient city in the wake of the destructive 2010 / 2011

earthquakes where more than 1000 commercial buildings in

Christchurch’s central business district were destroyed,

demolished and many are now being rebuilt.

Following the demolition phase, the city’s priority was to

rebuild infrastructure and power systems, including

underground services. Christchurch City Council opened the

recovery planning process to local businesses, property

owners, public sector organisations, residents and

community groups for ideas and comments on what they

wanted in the new city. The guiding principles that emerged

(CCC, 2011) were:

 To foster business investment,

 To respect the past,

 To have a long-term view to the future,

 To be easy to get around, and

 To create a vibrant central city.

The opportunity for major infrastructure re-building

provided a unique opportunity for installing shared energy

systems and improved power, water and sewerage

infrastructure. Longer term benefits including more energy

efficient resilient infrastructure using renewable lower

carbon sources of energy should feature in the rebuild

(Sustainable Cities, 2011). Unfortunately, the processes

around city energy networks were not set-up quickly enough

to enable the implementation of larger coordinated

initiatives, and businesses started to rebuild independently,

applying for energy consents individually or sometimes in

conjunction with near neighbours.

Proceedings 39th New Zealand Geothermal Workshop

22 - 24 November 2017

Rotorua, New Zealand

Figure 1: Conceptual diagram showing the groundwater flow from the foothills of the Southern Alps to the confined aquifers

under Christchurch. Image redrawn from Weeber (2008).

2.1 Geological and Hydrological setting

Christchurch is located above a series of aquifers, ranging

in depths from <13 m (Springston Formation) to depths

greater than 150 m (Figure 1). There are six separate

aquifer systems over this depth range in gravel alluvium

and glacial outwash deposits, confined by marine sediments

composed of silt, clay, peat and shelly sands, which act as

aquitards (Taylor et al, 1989).

(1) < 13 m Springston Formation (~10 m thick)

(2) 20-40 m Riccarton Gravels (~15 m thick)

(3) 50-85 m Linwood Gravels (variable thickness)

(4) 95-105 m Burwood Gravels (~5 m thick)

(5) 15- >125 m Wainonui Gravels (~5 m thick)

(6) >150 m Aquifer No 5

An artesian system occurs in the coastal area due to the

hydraulic gradient and the confining nature of the system

with the artesian pressure increasing with depth. The aquifer

transmissivities vary between <40 and up to 20,000 m

with the individual aquifer “averages” being between 1200

and 4300 m

/d (Rutter, 2015) The water temperatures are

generally between 11°C and 13°C, with water originating in

the Port Hills (south of the city) generally being warmer.

The first artesian wells were drilled in the 1860s in response

to a need for uncontaminated water supply (CCL, 2016). The

number of wells reached several thousand by the late 1980s,

accessing water from up to 200 m deep for agricultural,

industrial and domestic water supply.

3. CONSENT REQUIREMENTS AND POLICIES

Prior to the Christchurch earthquakes in 2010 and 2011, GHP

schemes were required to obtain consent to extract and

discharge to groundwater or surface water. Although the

regional plan operative at the time did not allow for new

consumptive groundwater takes, GHP schemes that injected

100% of the extracted water back to the aquifer system could

be consented. Thermal impacts were managed on an effects

basis, with applicants required to assess the potential for

effects on any temperature-sensitive wells within influencing

distance.

The opportunity to support and encourage development of

high efficiency building energy solutions as part of the post-

earthquake rebuild was recognised by a number of agencies.

The city and central government agencies offered funding

grants to support feasibility studies and a contribution

towards capital costs of GHP systems (CAfE, 2013; EECA,

2015; 2016). Several issues were identified by developers as

potential deterrents to aquifer based energy system. They

were:

(1) the additional time required for the consenting

process,

(2) the associated uncertainty, and

(3) the additional costs involved in gaining consent.

In 2013 the opportunity was taken by the Geothermal Heat

Pump Association of New Zealand and Central Heating New

Zealand, to seek revisions to the planning rules in the

proposed Canterbury Land and Water Regional Plan.

Submissions made (Carey, 2013) sought changes to:

(1) Allow flexibility in the depth and location of the water

and heat abstraction and discharge within groundwater

allocation zones;

(2) Clearly state that non-consumptive groundwater takes,

where the take and discharge are within the same

groundwater allocation zone, would not be subject to

any groundwater allocation zone limits regardless of

the depth and location of the take and discharge;

(3) Ensure that non-consumptive takes and discharges

would be managed in the context of the groundwater

allocation zone, not the single aquifer context; and

(4) Ensure that further non-consumptive groundwater

abstraction within the Christchurch - West Melton

groundwater allocation zone was not prohibited.

Proceedings 39th New Zealand Geothermal Workshop

22 - 24 November 2017

Rotorua, New Zealand

In 2015 there were rules introduced into the Canterbury Land

and Water Plan permitting certain water takes for aquifer

thermal energy systems that applied specifically to the

central city area. The provisions are included in rule 9.5.15

of the plan (ECan, 2015). Water could be used for energy

purposes provided it was taken and then discharged to

identified aquifers and that the takes and discharges

complied with other prescribed requirements. The water is

to be extracted from aquifers between 30 m to 100 m deep,

and discharged to the shallower Riccarton aquifer below 20

m deep. Discretionary applications can be made for permits

(rule 9.5.16) where the use doesn’t meet the requirements of

the permitted activity rule.

Almost all of the commercial aquifer energy installations in

the central Christchurch city area that have been installed in

the last few years or are being planned are based on specific

consents for their facilities even though the permitted activity

rule has been in place since 2015.

4. GHP INSTALLATIONS

4.1 Pre-Earthquake installations

The Townhall utilised the city water for heating and cooling

purposes in the 1970’s (Marshall, 2013), however the first

purpose-drilled wells for energy purposes were drilled in

1997 on the University of Canterbury’s campus. The

campus, currently has a series of seven bores ranging in

depths from 9 m to 60 m, which extract aquifer water at a

maximum rate of 5 L/s in the shallower wells, and a

maximum of 30 L/s in the deeper wells (Consent

CRC971519; ECan, 2016). The water is discharged to the

Avon River or the Okeover Stream at temperatures < 21°C.

In 2011, heat pumps and chillers were installed at

Christchurch Airport, located 12 km from the city centre.

The heat pump and chiller systems take advantage of the

12°C water in the subsurface aquifers to provide heating and

cooling to the airport buildings. Groundwater from six wells

at depths between 16 m and 40 m (Consent CRC074115.1;

ECan, 2016) pass through the heat plant being discharged

through a soak pit back into the ground. The system makes

use of a design with the water from the wells used to precool

or directly cool some components of the airport facilities.

The direct cooling bypasses the chiller systems further

enhancing the system energy effectiveness.

The airport system gained both national and international

industry recognition. It was awarded the Gold Award of

Excellence at the 2014 ACENZ Innovate NZ Awards and the

Building and Construction category at the 2014 IPENZ NZ

Engineering Excellence Awards. It won the International

Project of the Year at the 2015 CIBSE Building Performance

Awards in London.

4.2 Post 2011 Installations

The Christchurch rebuild has seen a surge in the installation

of GHP systems, unmatched elsewhere in New Zealand.

Table 1 has data for commercial facilities including the date

of completion. The influence of post 2010/11 earthquake

rebuilding on the uptake of the technology is apparent. The

table is colour coded with the known fully operational

facilities shown in green, the partially operational facilities

shown in blue and those under construction in white.

Facility

Floor

Area m2

Completion

University of Canterbury

1997 +

Christchurch International

Airport

2011

TAIT Technology Centre

Apr-15

Bus Exchange

9500

May-15

ECan office

8000

Mar-16

Art Centre

13000

2016-19

St Georges Hospital

2016-19

Justice Precinct

42000

Aug-17

The Terrace

4000

Oct-17

King Edward Barracks

30000

2017

Town Hall

11000

Jul-18

Central Library

9800

2018

School of Biological

Sciences

(University of Canterbury)

2019

Convention Centre

2020

Metro Sports Facility

34,000

2020

New Education Building

(University of Canterbury)

Table 1: Commercial facilities using or proposing to use aquifer

water energy.

Domestically, at least 30 GHP systems have been installed

since 2010 in the Canterbury region (GNS Science, 2017).

This is about the same number that had been installed in

Canterbury prior to the earthquake. However, it is the larger

scale, commercial sector which has experienced significant

growth since 2010/11. Seven of the new installations that

have been completed or are near-completion in Christchurch

are shown in Figure 2.

The paper goes on to discuss a number of these installations.

Data has been acquired for one of the smaller installations

(ECan offices) and this is discussed in more detail.

4.2.1 Bus Exchange

The Bus Exchange is a purpose built public transport facility

located in the core of Christchurch CBD. The design process

was relatively rapid as the retail spaces were already under

construction when the site became available for the

Exchange. The Bus Exchange occupies approximately

5,000m

catering for 8.6 million bus passengers per year and

approximately 1,850 buses per day (MFE, 2005). It became

operational in May 2015.

The building is heated and cooled by an aquifer GHP system,

which extracts water from a depth of 85 m (Linwood

Gravels) at a rate of up to 189,000 m

per year (Consent

CRC167902; ECan, 2016) and re-injects a similar quantity

of water at a depth of 36 m (Riccarton Gravels) (consent

CRC167904; ECan, 2016). The range of temperature change

permitted is ±6 °C.

Proceedings 39th New Zealand Geothermal Workshop

22 - 24 November 2017

Rotorua, New Zealand

Figure 2. Map showing location of new GHPs in Christchurch’s CBD. From Seward et al., 2017

4.2.2 The Arts Centre (The Performing Arts Precinct)

The Art Centre was originally established as a college

campus. Construction began with the Clock Tower block in

1877. A Girls’ High School opened the following year,

followed by the Boys’ High School three years later, and

other buildings were added as the campus expanded to also

include the University. The secondary schools moved away

from the site in 1881 and 1926, and by 1978, the University

had fully relocated to Ilam. The site’s buildings were then

transferred to the Arts Centre of Christchurch Trust Board for

a Performing Arts Precinct for creative performance, music,

drama, and dance.

Due to damage sustained from the earthquakes, an extensive

seven-year, $290 million restoration programme is currently

underway (CCC, 2015). During this period the site is to be

progressively re-opened in stages.

Prior to the earthquakes, the Art Centre Trust had considered

a GHP system to heat and cool the buildings. The heating and

cooling system for the facilities was reviewed in 2013 and

decisions to install an aquifer based GHP system made. Bores

were installed in 2014. The Art Centre is consented to take

water at rates of not more than 80 L/s (Consent CRC154729;

ECan, 2016), and inject the water with a temperature

difference range of +/- 6°C (Consent CRC154730; ECan,

2016). Four wells are used, two producing water and two

injecting water discharged from the heat plant. There are two

plant rooms as part of the site with seven heat pumps installed

between them.

4.2.3 ECan Offices

The Environmental Canterbury (ECan) offices opened in

early 2016, housing 450 staff over 5 floors, with a total floor

area of ~8000 m

(Stuff, 2016). It has a 4 Green Star rating

and is built to 120% of the current building code for building

strength. The building is heated by 0.65 MW heat plant using

artesian water. The water is extracted from well BX24/0527

(85 m depth) at a rate no greater than 33 L/s, up to a maximum

of 2500 m

per day and up to 350,000 m

per annum (average

11 L/s) (Consent CRC146483; ECan, 2016). The water is then

injected at 35 m, within a temperature range of +/- 8

C of the

extraction temperature (Consent CRC146484; ECan, 2016;).

Figure 3 is a photo of the submersible extraction pump (black

unit suspended from the crane) removed from the well.

Figure 3. ECan submersible extraction pump suspended

from crane.

Proceedings 39th New Zealand Geothermal Workshop

22 - 24 November 2017

Rotorua, New Zealand

Examples of monitored data from the ECan GHP heat plant

are shown in Figure 4 and 5 for February 2017. At a pump

rate of 30 L/s, the incoming water temperature is shown in

blue (left hand axis) and temperature difference is shown in

red (Right hand axis). The pump only operates for part of the

day and this is seen in the figure with the pump not operating

when the incoming water temperature is plotted below 5°C.

During the month of February the heat plant was operating in

cooling mode and Figure 5 is a plot of the calculated daily

energy (MJ per day) delivered to the aquifer from the heat

plant.

Figure 4. Incoming water temperature from bore BX24/0527 (Blue). Temperature difference of water injected into bore

BX24/0528 (Red – right hand vertical axis). Temperature change is positive with heat plant operating in cooling mode

Figure 5. Daily energy delivered to the aquifer (Green dots in MJ per day – right hand vertical axis) into bore BX24/0528

(Red data is temperature change – left hand vertical axis).

Proceedings 39th New Zealand Geothermal Workshop

22 - 24 November 2017

Rotorua, New Zealand

4.2.4 Justice Precinct

The Christchurch Justice and Emergency Services Precinct is

a $300 million development project that is purpose-built to

bring together the justice and emergency services. An

estimated 2,000 people will work in or utilise the Precinct

(MOJ, 2016).

The construction of the Precinct began in mid-2014, and it is

due for occupation in July / August 2017. It will be

constructed with advanced seismic design including base

isolation. The building has a floor area of approximately

40,000 m

over five floors and will utilise aquifer based GHP

heat plant. The system installed at the Justice Precinct will

extract groundwater through three bores drilled to around 150

m. The water discharged is injected back into the groundwater

at less than 90 m depth (Consent CRC165438; ECan, 2016).

The heat plant is rated for 3 MW of cooling and 2 MW of

heating and the annual energy delivered from the plant is

estimated to be 4.2 GWh for cooling and 2.2 GWh for heating.

4.2.5 The Terrace

The Terrace is a $120 million redevelopment of the

Christchurch hospitality precinct that will house 16

restaurants and bars, a large 4,000 m

office building and a

car park building.

Heating and cooling for part of the complex will be through a

500 kW heat pump extracting water from the Linwood

Formation (85 m deep) and returning water to the Riccarton

Gravel Formation (30 m). The temperature difference

between extraction and injection can be up to +/- 8°C. The

facility has been approved by the Canterbury Regional

Council to abstract groundwater at a rate of up to 47 L/s, to a

maximum volume of 830,000 m

per annum (averaged take

26.3 L/s) from two bores (Consent CRC156321; ECan, 2016),

and to discharge the water to the Riccarton gravel aquifer

(Consent CRC156322; ECan, 2016).

4.2.6 King Edward Barracks Site

The King Edward Barracks were built in 1905. It was used for

drilling and housing soldiers and later for civic functions and

social occasions until 1993. The area is now planned for a

combination of commercial, residential and parking buildings

(Ngai Tahu, 2015). The piazza and open urban spaces on the

site are to be utilised as public space. A 30,000 m

building is

planned for the area which will house offices and an

apartment complex. Up to 1,500 workers will occupy the site.

The King Edward Barracks site has been consented to extract

at a maximum rate of 80 L/s from a depth of 128 m, up to a

maximum of 1,264,896 m

per year (averaged take 40 L/s)

(Consent CRC168911; ECan, 2016). Heat is to be extracted

from the aquifer water using 1.5-2.5 MW heat plant. The

water will then be injected to a depth of 38.5 m (Consent

CRC168912; ECan, 2016) at a water temperature in the range

+/- 8°C from the extraction temperature.

4.2.7 Christchurch Town Hall

The Christchurch Town Hall suffered significant damage

during the 2011 earthquake, mostly due to liquefaction. The

main auditorium was able to be saved, but the rest of the

building was demolished. The rebuild began in November

2015 to install concrete piles into the ground to support the

auditorium and to provide stability in the event of future

liquefaction. The rebuild of the Town Hall aims to keep the

original charm and characteristics, while making it a state of

the art performance venue (CCC, 2015).

The original Town Hall that opened in 1972, was equipped

with a heat pump system that was well maintained utilising

the council’s mains cold water system to provide most of the

heating and cooling requirements of the building (Marshall,

2013). Unfortunately, this system suffered damage from the

flooding of the Avon River so will be replaced with a more

efficient aquifer based GHP heat plant that will extract

groundwater from 80 m depth and discharge the water to the

Avon River (Marshall, 2013).

5. SUMMARY

Geothermal heating and cooling technology in Christchurch

utilises the abundant renewable energy aquifer resource that

underlies the city. There has been significant growth in GHP

installations in Christchurch following the 2010/11

earthquakes. Fourteen large-scale commercial GHP

developments have been completed or are underway in the

city as part of the rebuild. These range in size up to 3 MW in

capacity serving buildings with floor areas of up to 40,000 m

This opportunity for GHP growth has been supported by

government incentives, a permissive rule frame framework, a

small network of experienced designers and installers

underpinned by a push for renewable and sustainable building

energy choices as part of the city rebuild.

The rate of domestic GHP installations in Canterbury has

continued to remain steady, at around ten per year.

Christchurch is leading the way in the New Zealand GHP

market, and surely stands as an exemplar of the uptake of this

technology for the rest of the nation.

ACKNOWLEDGEMENTS

This research was supported by New Zealand Government-

funded geothermal research funding at GNS Science. Thanks

to designers, installers and companies who provided technical

information on the Christchurch GHP installations and the

history for this paper.

REFERENCES

CAfE (Christchurch Agency for Energy), Christchurch

Energy Grants. Retrieve September 2016 from:

https://www.ccc.govt.nz/the-council/council-controlled-

organisations/trusts/christchurch-agency-for-energy-

trust-cafe/ (2013)

Carey, B.S. Statement of Evidence of Mr Brian Stewart

Carey, IN THE MATTER of the Resource Management

Act 1991 and IN THE MATTER of the Environment

Canterbury (Temporary Commissioners and Improved

Water Management Act) 2010, and IN THE MATTER of

the hearing of submissions on the Proposed Canterbury

Land and Water Regional Plan. (2013)

Carey, B., Dunstall, M., McClintock, S., White, B., Bignall,

G., Luketina, K., Robson, B., Zarrouk, S., Seward, A.

2015 New Zealand Country Update. Proceedings: World

Geothermal Congress, Melbourne Australia, April 2015.

(2015)

CCC (Christchurch City Council), Rebuilding the Central

City with the Performing Arts: The Vision for the

Performing Arts Precinct. 48p. Retrieved from:

https://www.ccc.govt.nz/the-rebuild/arts-and-

culture/performingarts/. (2015)

CCC (Christchurch City Council), Central City Plan.

Retrieved September 2016 from:

https://www.ccc.govt.nz/the-council/plans-strategies-

policies-and-bylaws/plans/central-city-recovery-plan/.

(2011)

Proceedings 39th New Zealand Geothermal Workshop

22 - 24 November 2017

Rotorua, New Zealand

CCL (Christchurch city Library). Early Christchurch – a brief

history. Accessed Oct 2016, from

http://my.christchurchcitylibraries.com/christchurch-

brief-history/. (2016)

Climo, M., Lind, L., Carey, B., and Bendall, S. The rise and

rise of geothermal heat pumps in New Zealand. In:

Proceedings 34th New Zealand Geothermal Workshop,

19-21 November 2012, Auckland, New Zealand, 7p.

(2012)

Coyle, F. Architect’s, engineer’s and energy manager’s

perceptions of low temperature geothermal and biomass

energy technologies; barriers to uptake and their potential

solutions. GNS Science Report, 2014/12. 116p. (2014)

ECan (Environment Canterbury), Environment Canterbury

Consent Search. Database retrieved from:

http://ECan.govt.nz/services/online-

services/pages/consent-search.aspx (2016)

ECan (Environment Canterbury), August 2015. Canterbury

Land and Water Regional Plan Volume 1. Report

R17/12, ISBN 978-1-98-852028-5 (Web). Available

from ECan website. (2015)

EECA (Energy Efficiency and Conservation Authority),

Industrial Systems Design Advice. EECA Business

Support. Retrieved September 2016 from:

https://www.eecabusiness.govt.nz/assets/Resources-

Business/industrial-systems-design-advice-sept-2015.pdf

(2015)

EECA (Energy Efficiency and Conservation Authority),

Feasibility Studies and Business Cases. EECA Business

Support. Retrieved September 2016 from:

https://www.eecabusiness.govt.nz/assets/Uploads/EEC4

039-EECA-Business-Collateral-Feasibility_FA.pdf

(2016)

GNS Science, New Zealand Geothermal Use Database.

Retrieved from: data.gns.cri.nz/geothermal/. (2017)

Lind, L., Swedish Ground Source Heat Pump Case Study

(2010 Revision), GNS Science report 2010/54. 30p

(2011)

Marshall, P. Christchurch Town Hall for Performing Arts:

CCC Workshop Final Design Report. Warren and

Mahoney. Retrieved 9 July 2016 from

resources.ccc.govt.nz/files/CityLeisure/projectstoimprov

echristchurch/christchurchtownhall/LoResChristchurch_

Townhall_EQ_Repair_CCC_Workshop_13.08.2013_H

R.pdf. (2013)

MFE (Ministry for the Environment), Christchurch Bus

Exchange. Urban Design Case Studies. ME 581.

Retrieved September 2016 from

http://www.mfe.govt.nz/publications/towns-and-

cities/urban-design-case-studies/christchurch-bus-

exchange. (2005)

MOJ (Ministry of Justice), Christchurch Justice &

Emergency Services Precinct. Retrieved September 2016

from: https://www.justice.govt.nz/about/about-us/our-

strategy/christchurch-justice-and-emergency-services-

precinct/. (2016)

Ngai Tahu. Ngāi Tahu Property announces master plan for

King Edward Barracks Site. Retrieved September 2016

from: http://ngaitahuproperty.co.nz/news/213-ngai-

tahu-property-announces-master-plan-for-king-edward-

barracks-site. (2015)

Rutter, H., \ Hydrogeology of Christchurch. Aqualinc

Presentation. 15 June 2015.

http://nzgeothermal.org.nz/ghanz/wp-

content/uploads/sites/4/2016/11/12June2015_1-

2_AQUALINC-Rutter.pdf (2015)

Seward, A., Climo, M., Rutter, H., Etheridge, Z., Van Meer,

P., Bendall, S., and Carey, B., Rebuilding Christchurch

– Using Ground Source Heat Pumps In Proceedings 12

IEA Heat Pump Conference (2017)

Stuff, 2016. Environment Canterbury boosts inner city

workforce in new $51 million building. Published 18

April 2016. Retrieved from: http://www.stuff.co.nz/the-

press/business/the-rebuild/79042612/Environment-

Canterbury-boosts-inner-city-workforce-in-new-51-

million-building. (2016)

Sustainable Cities, Christchurch Regeneration. Report.

Retrieved August 2016 from:

http://sustainablecities.org.nz/wp-content/uploads/Wn-

ChCh-Regeneration-Book-11.pdf (2011)

Taylor, C.B., Wilson, D.D., Brown, L.J., Stewart, M.K.,

Burden, R.J., Brailsford, G.W. Sources and flow of North

Canterbury Plains groundwater, New Zealand. Journal of

Hydrology 106, 311-340. (1989)

Weber, J., Bendall, B., Bertani, R., Bromley, C., Busby, J.,

Gregorio, M., Guomundsdottir, M., Ketilsson, J., Link,

K., Muller, J., Nathwani, J., Mieve, D., Rocher, P.,

Romagnoli, P., Scholtysik, S., Siddiqi, G., Song, Y.,

Thompson, A., Tosha, T, and Wissing, L., Geothermal

Trend Report 2014, IEA Geothermal Implementing

Agreement, pp 48. (2014)

Weeber, J., 2008. A hydrogeology basis for zone boundaries,

variations 6 to the proposed natural Resource Plan. Report

no. U08/21. ISBN 978-1-86937-802-8.