Re: Outputs from GNS Science Hydrogeology Research Programmes

Letter Report No: CR 2017/224 LR Project No: 630HG107-00

24 November 2017 Wairakei Research Centre 114 Karetoto Road RD 4 Taupo 3384 Private Bag 2000 Taupo Mail Centre Taupo 3352 New Zealand T +64-7-374 8211 F +64-7-374 8199 Dear Stakeholder www.gns.cri.nz

Re: Outputs from GNS Science Hydrogeology Research programmes

This document reports on GNS Science’s hydrogeology-related research outputs for the period July 2016 to October 2017. If you are interested in finding out more about these research topics and potential applications, please get in touch with the relevant contact person provided.

The aim of our hydrogeological research is to answer the high-level question: How can we improve the sustainable management of, and economic returns from, New Zealand’s groundwater resources?

We hope you will find this information useful. Please do not hesitate to contact us if you would like to give us feedback or comments.

Yours sincerely

Magali Moreau Stewart Cameron Groundwater Geochemist Head of Department Hydrogeology

On behalf of contributing authors:

Abigail Lovett Alexander Kmoch Brioch Hemmings Conny Tschritter Catherine Moore Chris Daughney Heather Martindale Jeremy White Johannes Kaiser Liz Keller Matt Knowling Mike Friedel Mike Stewart Mike Toews Paul White Rachel Franzblau Richard Levy Rob van der Raaij Rogier Westerhoff Simon Cox

Troy Baisden Uwe Morgenstern Zara Rawlinson

Page 1 of 26 Institute of Geological and Nuclear Sciences Limited

Our hydrogeology research activities are undertaken as part of seven different research programmes, funded by the Ministry of Business, Innovation & Employment (MBIE), including the Strategic Science Investment Fund (SSIF):

• Groundwater Resources of New Zealand (GWR): This programme aims to: understand the hydrogeological and structural characteristics of New Zealand’s aquifers; determine fluxes of water and key substances in, through, and out of these aquifers; develop and apply isotopic tools and biogeochemical tracers; determine impacts of pressures (e.g., human activities and climate change) on groundwater resources; and to assist stakeholders to improve social, cultural, environmental and economic outcomes. Duration: 2011-2024. Contact: Abigail Lovett, [email protected].

• National Groundwater Monitoring Programme (NGMP): This programme provides a national perspective on groundwater quality, defines “baseline” groundwater quality, associates groundwater quality with certain causes such as anthropogenic influence, and provides best-practice methods for sampling and monitoring as well as groundwater quality data interpretation. The NGMP consists of three components: operations (collaboration with all New Zealand regional authorities); research and database. Duration: national coverage for the network was attained in 1998; research activities started in 2002. This programme was part of GWR up to 2016 and is now part of GNS Science’s Nationally Significant Databases and Collections. Contact: Magali Moreau, [email protected].

• Smart Models for Aquifer Managements (SAM): This programme develops effective and streamlined groundwater surface water flow and transport models, at local (well or spring) to large (catchment or regional)-scales. The SAM programme also provides methods for identifying optimal data acquisition efforts for multi-scale predictions. The resulting models are suitable for quantification of uncertainty and run sufficiently quickly to support a comprehensive risk-based evaluation of design or policy alternatives. These models can be rapidly built and therefore cost less to deploy than is the current norm; thus, providing more widespread model based support for any model budget. This programme is a collaborative initiative between GNS Science (Lead), National Institute for Water and Atmospheric Research (NIWA), the Institute of Environmental Science and Research (ESR), the University of Waikato, Victoria University, Market Economics, Greater Wellington Regional Council, Waikato Regional Council and Environment Southland. Duration: 2015-2018. Contact: Catherine Moore, [email protected].

• Te Pūnaha Hihiko – Vision Mātauranga (VM):

o Incorporating environmental and indigenous knowledge for future management of freshwater resources in the Piako Catchment (VM-P): This project is a collaboration with Hauraki iwi Ngāti Hauā to collate freshwater scientific, mātauranga-a-iwi and policy knowledge about the Piako River catchment and make it available within an interactive user-focussed tool. The information will enable Ngāti Hauā to more readily make informed decisions about freshwater resource management in the Piako Catchment for both the health of the environment and the iwi. As part of the project, there will be hands-on marae-based workshops to share knowledge, and to facilitate learning through experience. Duration: 2017-2019. Contact: Zara Rawlinson, [email protected].

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o Identification of ‘kaitiaki’ flow regimes for the Awahou Stream (VM-K): This programme is a collaboration with Rotorua iwi Ngāti Rangiwewehi to identify ‘kaitiaki’ flow regimes for Awahou Stream near Rotorua. This is a new water management concept for spring-fed catchments that will bring together science and mātauranga (traditional knowledge). One of the outputs will be a water resources capability plan, which will be promulgated to other iwi and water suppliers and is expected to help other iwi with their water resources capability development. Duration: 2017-2019. Contact: Paul White, [email protected].

• Measuring groundwater denitrification (MGD): This project will develop and validate a new method for quantifying denitrification in groundwater systems, based on measurement of “excess” nitrogen gas (N2). The project is funded by the “Innovative and Resilient Land and Water Use” theme of the Our Land and Water, National Science Challenge. All groundwaters contain dissolved gases derived from the atmosphere during recharge, including N2. In addition to the dissolved atmospheric N2, groundwaters can also contain excess N2 that accumulated from denitrification reactions. The dissolved atmospheric N2, at the time the water entered the groundwater system, can be established by the measurement of noble gases that are part of the atmosphere, usually argon (Ar) and neon (Ne). This enables differentiation of the excess N2 produced via denitrification reactions from atmospherically derived dissolved N2. The project will develop a method to measure Ne in addition to our existing Ar and N2 techniques, and use the measurement of the three gases to measure excess N2 in pilot studies. the neon method will also increase the accuracy of sulphur hexachloride (SF6) dating through better constraining excess air which impacts the water ages derived from the SF6 tracer. Duration: 2016-2018. Contact: Heather Martindale, [email protected].

• National Hydrology Programme (NHP): This programme aims to improve national- scale hydrological knowledge across the New Zealand landscape with a combination of data on surface water, soil, geology and groundwater. Case studies areas includes catchments located in the Gisborne, Horizons and Southland regions. This programme brings together NIWA (leading organisation), Landcare Research and GNS Science. In the NHP, GNS Science will further develop their models of groundwater flow, groundwater age, and hydraulic properties of the subsurface. Duration: 2016-2023. Contact: Rogier Westerhoff, [email protected].

• Smart Aquifer Characterisation (SAC): This programme aimed to develop a suite of innovative methods for characterising New Zealand’s groundwater systems faster and/or less expensively than using traditional methods. Duration: 2011-2017, completed in September 2017. Contact: Stewart Cameron, [email protected].

In addition, GNS Science received funding from regional councils and from NIWA’s “Waterscape” programme that allows us to contribute our groundwater science to water resource characterisation and management.

Below our above-listed main research question, our programmes are structured into five second-level questions, each of which is addressed through specific activities. Our research questions (RQs) relate to priority research areas (Appendix 1) defined by the New Zealand Groundwater Forum (Envirolink 2017). For your convenience, all outputs are listed in Table 1.1, clicking on individual outputs or questions will bring you directly to the relevant content.

Envirolink. 2017. Regional Groundwater Forum. 2017 Special Interest Group Workshop – Regional Groundwater Forum. [accessed 2017 Nov 23]. http://www.envirolink.govt.nz/assets/Envirolink/2.- Groundwater-Forum.pdf.

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Table 1.1 GNS Science Hydrogeology RQs and science outputs. (In the electronic version of this report, click on each question or output to link to it)

Hydrogeology Research output Why it’s important Department RQs (July 2016 to October 2017) Second step toward a seamless, nationally 1.1 Mapping New Zealand Hydrogeological consistent, map and classification of Systems. New Zealand aquifers.

Defensible groundwater catchment 1.2 Uncertainty quantification around Lake Rotorua boundaries supporting freshwater groundwater catchment boundaries. management policies.

Fundamental to understanding the 3D 1.3 Upper Waikato River catchment 3D geological distribution of our aquifers and supporting model. groundwater flow model development. The 3D relationship between geology and 1.4 Geomorphic model for the Wairau Plains. ground morphology is relevant to the definition of groundwater catchments. 1. What are the hydrogeological and 1.5 Refinement of Quaternary sediments in the 3D Quaternary deposits host most of structural geological model. New Zealand’s groundwater resources. characteristics of New Zealand's Enables optimisation of new data aquifer systems? 1.6 Data worth analysis to inform data acquisition acquisition to minimise cost while reducing plans. the uncertainty of groundwater model predictions Support understanding hydrogeological 1.7 A national hydroseismicity dataset for the 2016 responses to large earthquakes and Mw 7.8 Kaikoura earthquake, New Zealand. therefore to develop resilience to future events. 1.8 Hydrologic changes within large geoengineered As per 1.7. groundwater systems.

1.9 New Zealand guidelines for the application of Guidance to select and apply smart SMART Aquifer Characterisation techniques. techniques for aquifer characterisation.

Provides isotopic input that supports rainfall 2.1 A stable isotopes map for New Zealand recharge and groundwater flow modelling groundwaters. and or interpretation. This model can be used to fill in data in data-sparse areas and to give estimates of 2.2 Nationwide model of groundwater recharge. depth to water table, and hydraulic conductivity at national scale. Lysimeters provide in-situ groundwater 2.3 Quality Assurance /Quality Control of rainfall recharge measurements (in conjunction recharge data. with ground-level rain gauge). 2.4 Recharge monitoring sites installed in the 2. What are the fluxes As per 2.3. of water into, out Auckland Region. of, and through Robust transient groundwater age transport 2.5 Addressing the Old Water Paradox using New Zealand's models are required for assessing drinking tritium. aquifers? water security. 2.6 Solving aggregation errors of tritium ages through the non-linearity between age tracer As per 2.5. concentrations and age. Understanding seasonal variation in 2.7 Using binary mixing models to address ingress groundwater source at monitoring wells of young water into generally old waters. supports interpretation of change in groundwater quality. This low-cost tracer technique has been 2.8 Further radon applications to identify developed to locate and quantify surface groundwater discharge locations and fluxes. water connections.

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Hydrogeology Research output Why it’s important Department RQs (July 2016 to October 2017) Combined interpretation allows maximal 2.9 Combined age tracer interpretation reveals use of existing data and improves system regional groundwater processes. understanding. Calibrated groundwater age models 2.10 National Tracer Survey. support groundwater flow and transport modelling Supports characterisation of the state and 3.1 National groundwater quality monitoring. trends, through time, of New Zealand groundwaters. Determining chemical concentration 3.2 Baseline trends for New Zealand groundwaters baseline natural rates of changes provides 3. What are the fluxes of using a machine-learning-augmented dataset. key substances into, context to define anomalous trends. out of and through Determining the type and quantities of New Zealand's emerging organic contaminants is required 3.3 First regional groundwater baseline survey for aquifers? to design adequate monitoring and target emerging organic contaminant in preparation. the development of New Zealand analytical capabilities to support this monitoring. 3.4 Groundwater transport modelling for Pathogen transport models are key to pathogens. ensure drinking-water security. Has implications for New Zealand’s future 4.1 Modelling the impact of sea-level rise in the negotiating position on climate change Heretaunga Plains. mitigation and informs regional and national climate change reliance plans.

4.2 Changes in pasture production under climate As per 4.1. change scenarios.

4.3 Theoretical foundation for the model stream Fast and reliable models are needed to lining. timely inform management decisions. 4. How have/will human activities, climate 4.4 Decision focus for model simplification. As per 4.3. change and other pressures affect 4.5 Development of synthetic models for SAM. As per 4.3. New Zealand's groundwater 4.6 Stream lined models to assess water and land resources? use management issues and the limit setting As per 4.3. process, three case studies.

4.7 Commercial regional flow and transport Informs a variety of decisions relating to modelling work. land- and water-use.

4.8 Satellite data for wetland dynamics. Informs rapid-response to flood mitigation.

4.9 Assessment of water source and contaminant Combined isotopic and hydrochemical pathways in the Waiokura Catchment using tracers are a powerful tool for discriminating hydrochemical and isotopic methods. water origin. 5.1 Knowledge transfer / outreach. Direct exchange with stakeholders. Supports regular national reporting on the 5.2 Continued contribution to the development of environment by the New Zealand Ministry national and international standards. 5. How can we ensure for the Environment (MfE). that stakeholders will use our research 5.3 Consolidating metadata of our national Supports robust monitoring and data results appropriately datasets. transparency. and efficiently? Free resources to support environmental 5.4 Web-accessible groundwater resources. analysis (including access to the national groundwater quality database).

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RQ1. What are the hydrogeological and structural characteristics of New Zealand's aquifer systems?

Output 1.1 Mapping New Zealand Hydrogeological Systems: Southland case study (GWR funded)

The Southland region was selected as a case study to develop a national classification for hydrogeological systems (Figure 1.1). These systems are defined as geographical areas with broadly-consistent hydrogeological properties and similar resource pressures and management issues using a tiered approach. The three tiers encapsulate an increasing level of information such as deposition environment or descriptive elements. Each system is uniquely identified, and assigned a suite of attributes (e.g., unique name, representative lithological profile). Some of these attributes allow mapping of features across systems (e.g., river valley fills along the full river reach across hydrogeological systems). Datasets used include geology (QMAP), digital terrain models, topographic contours, surface drainage information, hydrogeological classes and relevant publications (e.g., Quaternary shorelines, uplift and subsidence monitoring). This GIS-based classification will be used to consistently, rapidly and seamlessly define and map New Zealand aquifer systems, updating the 2001 aquifer map (White 2001) using recent digital data.

Figure 1.1: Six hydrogeological systems were mapped in the Southland region (left), and each was associated with one or more lithological profiles (right).

Moreau M, White PA, Tschritter C, Rawlinson ZJ, Westerhoff R, Kees LJ. Forthcoming 2017. A national classification for hydrogeological systems. In: New Zealand Hydrological Society Annual Conference; 2017 Nov 28-Dec 1; Napier, New Zealand. Wellington (NZ): New Zealand Hydrological Society. Tschritter C, Westerhoff R, Rawlinson Z, White P. 2016. Aquifer classification and mapping at the national scale – Phase 1: Identification of hydrogeological units. Lower Hutt (NZ): GNS Science. 52 p. (GNS Science report; 2016/51). doi: 10.21420/G2101S.

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Output 1.2 Uncertainty quantification of Lake Rotorua groundwater catchment boundaries (Bay of Plenty Regional Council funded)

The location of groundwater catchment boundaries is commonly uncertain, particularly where the boundary crosses wide, flat volcanic plateaus in the central North Island. The groundwater catchment of Lake Rotorua was mapped by GNS Science and NIWA. This mapping included an analysis of uncertainty in surface flow and other water budget parameters. The uncertainty in the catchment boundary was calculated as 95th percentiles of linear distances around the mean boundary. This uncertainty analysis promotes robust conclusions in water management applications with ‘improved public acceptance of a controversial water management policy’, namely the Bay of Plenty Regional Council policy to restore the quality of lake Rotorua.

McMillan H, Seibert J, Petersen-Overleir A, Lang M, White PA, Snelder T, Rutherford K, Krueger T, Mason R, Kiang J. 2017. How uncertainty analysis of streamflow data can reduce costs and promote robust decisions in water management applications. Water Resources Research. 53 (7): 5220-5228. doi: 10.1002/2016WR020328.

Output 1.3 Upper Waikato River catchment 3D geological model (Waikato Regional Council funded)

A 3D geological model of the Upper Waikato river catchment was developed for Waikato Regional Council to inform assessments of groundwater flow and quality. The model represents geological units in the area that are important for groundwater flow, including aquifers and aquicludes. Twenty model layers were defined, with each model layer representing units of similar groundwater flow properties. One specificity of the model was the dominance of Pleistocene Taupo Volcanic Zone volcanic units, with associated volcaniclastic sediments, and basement greywacke. The entire model is currently on display at the Waikato Museum, Hamilton, and part of the model is being used as fundament of a groundwater flow model.

White PA, Tschritter C. 2016. Geological model of the Upper Waikato catchment. Lower Hutt (NZ): GNS Science. 41 p. (GNS Science consultancy report; 2015/199).

Output 1.4 Geomorphic model for the Wairau Plains (Marlborough District Council funded)

Following last years’ work on geological controls of spring-fed stream catchments, a geomorphic model comprising seven geomorphic units, representative of the geology of the Wairau Plains for the last 20,000 years was developed. Geomorphic units represent geology and morphology and are used for describing the distribution and features (e.g., lithology) of aquifers and aquicludes. These units include the key lithologies associated with groundwater flow in the Plains, e.g., Holocene units (terrestrial gravels, estuarine sediments and beach gravels) and basement. The model shows the three-dimensional relationship between aquifers (i.e., gravels) and aquitards (e.g., estuarine sands and silts) and is therefore relevant to the definition of groundwater catchments of spring-fed streams and the assessment of land use and surface water quality.

White PA, Tschritter C, Davidson P. 2016. Geological controls on groundwater flow to spring-fed streams as determined by three-dimensional models of sedimentary lithologies and piezometric levels, lower Wairau Plain, Marlborough, New Zealand. Journal of Hydrology (NZ). 55 (1): 25-43.

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Output 1.5 Refinement of Quaternary sediments in the 3D geological model (GWR, GNS Science SSIF, Environment Southland via Envirolink, co-funded)

Quaternary deposits host significant groundwater resources in New Zealand. However, the lateral and vertical distribution of theses deposits is often poorly constrained. For instance, Quaternary deposits, which host most of Southland’s groundwater resources, were represented as a single layer in the regional-scale 3D geological model, due to limited data availability. This project aimed to identify a methodology to refine the Quaternary layer at a catchment-scale to enable an improved understanding of groundwater flow paths within the sediments. Geostatistics and machine learning algorithms (self-organising maps, K-means clustering) were trialled to identify patterns in groundwater well and coal bore logs. Preliminary results indicated that the inclusion of additional datasets (e.g., chemistry, QMAP), is required to derive meaningful correlation, planned for Phase 2 of the project. The information was used to inform the groundwater flow model for the Mid-Mataura catchment.

Output 1.6 Data worth analysis to inform data acquisition plans (SAC funded)

The data worth method assesses the cost-effectiveness of any existing or potential future data acquisition efforts, including monitoring regimes, using a model framework. This method is currently being applied in four case studies, where a model exists and data were acquired as part of the SAC programme. The Cromwell case study assesses the worth of using airborne electro-magnetic data to inform the spatial distribution of hydraulic parameters. The Hutt Valley case study estimated the value of using halon tracer data to enhance the reliability of groundwater travel time predictions. The Lake Rotorua case study investigated whether the greater spatial frequency of data from distributed temperature sensing improved the reliability of stream depletion predictions where there were discrete spring inputs rather than diffuse groundwater inflow to surface water. The Mid-Mataura study will focus on whether enhanced spatial representation of rainfall recharge, derived from satellite remote sensing, improves the reliability of predictions of land use impacts on surface waters. All case studies include a comparison with similar data acquisition using traditional techniques.

Moore C, Rawlinson Z, Moreau M. Forthcoming 2017. Use and worth of airborne-electromagnetic data for defining aquifer hydraulic properties. In: New Zealand Hydrological Society Annual Conference; 2017 Nov 28-Dec 1; Napier, New Zealand. Wellington (NZ): New Zealand Hydrological Society. Toews M, Moore C, Knowling M, Beyer M. Forthcoming 2017. An assessment of the worth and cost- effectiveness of novel age tracers in enhancing the reliability of groundwater travel time predictions. In: New Zealand Hydrological Society Annual Conference; 2017 Nov 28-Dec 1; Napier, New Zealand. Wellington (NZ): New Zealand Hydrological Society.

Output 1.7 A national hydroseismicity dataset for the 2016 Mw 7.8 Kaikoura earthquake, New Zealand (Victoria University, GNS Science SSIF, Aqualinc Ltd, co-funded)

A large national dataset was compiled from data collected by multiple organisations and observation sites (438 bores, 365 seismic stations, 131 river gauges, 64 climate stations, 10 weir gauges, 4 springs, and 1 lake). This datasets documents New Zealand’s second largest earthquake since European settlement (Kaikoura, Mw 7.8; propagation over 170 km; vertical fault displacement of up to 12 m). It resulted in a variety of hydrological responses including: liquefaction; groundwater level, temperature and turbidity change; and spring, river and lake level perturbations. Responses were either transient (hours), persistent (days), medium-term (months), or could be long-term (years to decades). These data, which comprise the most extensive “hydroseismicity” data-set ever compiled in NZ, and one of the largest internationally, will be used to characterise relationships between subsurface damage, long-term aquifer

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changes, and ground motion characteristics (Modified Mercalli shaking intensities, for example), to help New Zealand understand hydrogeological responses to large earthquakes and develop resilience to future events.

Weaver KC, Cox SC, Holden C, Rutter HK, Townend J. Forthcoming 2017. Hydrological effects of the 2016 MW 7.8 Kaikoura earthquake, New Zealand. In: New Zealand Hydrological Society Annual Conference; 2017 Nov 28-Dec 1; Napier, New Zealand. Wellington (NZ): New Zealand Hydrological Society.

Output 1.8 Hydrologic changes within large geoengineered groundwater systems (New Zealand Earthquake Commission, the Royal Society of New Zealand Marsden Fund, Victoria University of Wellington and OMV New Zealand Ltd, co-funded)

The character of hydrologic response to 11 large (Mw > 6.2) earthquakes of seven large geoengineered groundwater systems (deep-seated, previously slow-creep schist landslides) in the Cromwell Gorge was investigated in terms of spectral characteristics and energy. The groundwater level changes (metre- or centimetre-scale) recorded at 22 piezometers exhibited consistent characteristics with time to peak-pressure changes taking approximately one month and recovery lasting up to over a year. Changes in 11 weir flow rates were near instantaneous and followed by recession lasting ~one month. The response at each site were systematic from one earthquake to another in terms of duration, polarity, and amplitude. Consistent patterns in amplitude and duration have been compared between sites and with earthquake parameters (peak ground acceleration, seismic energy density, shaking duration, frequency bandwidth, and site amplitude). Landslide hydrological systems appear most susceptible to damage and hydraulic changes when earthquakes emit broad-frequency, long-duration, high-amplitude ground motion.

O’Brien GA, Cox SC, Townend J. 2016, Spatially and temporally systematic hydrologic changes within large geoengineered landslides, Cromwell Gorge, New Zealand, induced by multiple regional earthquakes. Journal of Geophysical Research – Solid Earth. 121 (12): 8750-8773. doi:10.1002/2016JB013418.

Output 1.9 New Zealand guidelines for the application of SMART Aquifer Characterisation techniques (SAC funded)

“Guidelines for the application of SMART Aquifer Characterisation techniques in New Zealand” will be published in early 2018 to facilitate the dissemination of techniques for aquifer characterisation that were researched as part of the SAC programme. It is intended that this guideline document will be used by water managers to enable informed decision making when applying novel techniques for aquifer characterisation. The guidelines focus on techniques that were developed and/or applied in New Zealand for the first time for informing:

• aquifer structure and hydraulic properties; • aquifer volume; • fluxes of groundwater interchange with surface waters; • water age; • uncertainty quantification; and • data synthesis and visualisation.

Decision charts will be provided for selecting an appropriate technique and additional references and contact details are provided to enable readers to further investigate these techniques.

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RQ2. What are the fluxes of water into, out of, and through New Zealand's aquifers?

Output 2.1 A stable isotopes map for New Zealand groundwaters (GWR funded)

Hundreds of nationwide groundwater stable isotope data (δ18O and δ2H) were compiled to provide a spatiotemporal distribution of groundwater stable isotopes suitable for identification of regional flow processes and a source of estimated isotopic values at unmonitored sites. These measurements were taken as part of the tritium calibration procedure, on the distilled water sample, before and after enrichment. It was subsequently corrected for isotopic shift induced during the sample distillation process. The accumulated stable isotope data will be added to the current dataset of stable isotopes in rainfall to obtain a higher spatial resolution of stable isotope signature in New Zealand catchments and can be used to refine current stable isotope precipitation models.

Trompetter VJ, van der Raaij RW. 2016. A stable isotope map of New Zealand groundwaters. In: New Zealand Hydrological Society Annual Conference; 2016 Nov 28-Dec 2; Queenstown, New Zealand. p. 162. Wellington (NZ): New Zealand Hydrological Society. Baisden WT, Keller ED, Van Hale R, Frew RD, Wassenaar LI. 2016. Precipitation isoscapes for New Zealand: enhanced temporal detail using precipitation-weighted daily climatology. Isotopes in environmental and health studies. 52 (4-5): 343-352. doi:10.1080/10256016.2016.1153472.

Output 2.2 Nationwide model of groundwater recharge (SAC funded)

A nationwide model of groundwater recharge based on satellite data of evapotranspiration and vegetation was developed. Estimated recharge was provided with monthly time steps and 1 km x 1 km resolution consistently across all regions. This recharge model was in turn used to develop a groundwater model to characterise the groundwater table across mainland New Zealand. The recharge results have been applied by Waikato Regional Council in a comparative study in the Waipa River catchment. The groundwater table model (called ‘National Water Table’) is currently being further developed in the NHP programme.

Westerhoff R, Miguez-Macho G, White P. 2017. Improvements to a global-scale groundwater model to estimate the water table across New Zealand [abstract]. In: European Geosciences Union General Assembly; 2017 April 23-28; Vienna, Austria. Goettingen (DE): Copernicus Gesellschaft. EGU2017- 19232. (Geophysical research abstracts; 19). Werner M, Westerhoff R, Moore C. 2017. Sensitivity of quantitative groundwater recharge estimates to volumetric and distribution uncertainty in rainfall forcing products [abstract]. In: European Geosciences Union General Assembly; 2017 April 23-28; Vienna, Austria. Goettingen (DE): Copernicus Gesellschaft. EGU2017-11091. (Geophysical research abstracts; 19).

Output 2.3 Quality Assurance/Quality Control of rainfall recharge data (Waterscape, Hawke’s Bay Regional Council, co-funded)

The Hawke’s Bay Regional Council has installed a network of five groundwater recharge measurement sites in the region (Heretaunga and Ruataniwha plains). Quality assurance and quality control (QA/QC) checks were completed on data collected at the four rainfall recharge sites in the period 2011-2014. Each installation consists of three lysimeters, a ground-level tipping-bucket rainfall recorder and a ground-level rainfall storage gauge. In addition, rainfall recharge measurements at these sites were supplemented with climate observations that were available at, or in the immediate vicinity of, the rainfall recharge sites. QA/QC checks included field and office checks by Hawke’s Bay Regional Council using their standard procedures for

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monitoring data, e.g., site and instrument maintenance; checks of data logger function; removal of test tips; verification of data, with identification of false data or missing data; and quality-coding of the data. Further QA/QC checks on the data sets were completed by GNS Science including: identification of dataset gaps, outliers, and observational drift over time. Continuous datasets were assembled by filling gaps in the recorded data with best- estimates of environmental variables based on observations at nearby sites.

White PA, Lovett AP, Gordon D. 2017. Quality control and quality assurance of Hawke’s Bay rainfall recharge measurements: 2011 – 2014. Lower Hutt (NZ): GNS Science. 21 p. (GNS Science report; 2016/16).

Output 2.4 Recharge monitoring sites installed in the Auckland Region (Auckland Council funded)

Two rainfall recharge monitoring sites were installed in collaboration with Auckland Council, and are located at Karaka and Puni, near Pukekohe. The installations provide the first direct measurements of groundwater recharge in the Auckland region. Datasets from these sites contribute to more than 20 in-situ recharge monitoring sites located in five regions throughout New Zealand.

Lovett, A. 2016. Installation of Karaka and Puni rainfall recharge monitoring sites, Auckland. Lower Hutt (NZ): GNS Science. 35 p. (GNS Science consultancy report; 2016/167).

Output 2.5 Addressing the Old Water Paradox using tritium (GWR, Monash University, co-funded)

The Old Water Paradox, a grand challenge for catchment hydrology, is that much of the water that contributes to streamflows during high flow events appears to be derived from relatively old groundwater stored in the catchment. The Water Dating Laboratory team, in collaboration with Monash University, achieved a new breakthrough in addressing this paradox using our tritium method owing to unmatched tritium accuracy. Tritium indicates that the event water in the streams is supplied by the soil/regolith.

Cartwright I, Morgenstern U. 2017. Addressing the Old Water Paradox using tritium [abstract]. In: European Geosciences Union General Assembly; 2017 April 23-28; Vienna, Austria. Goettingen (DE): Copernicus Gesellschaft. EGU2017-1818. (Geophysical research abstracts; 19).

Output 2.6 Solving aggregation errors of tritium ages through the non-linearity between age tracer concentrations and age (GWR, Public Works Research Institute, National Graduate Institute for Policy Studies, Akademia Górniczo Hutnicza University of Science and Technology, co-funded)

Aggregation errors due to spatial heterogeneity causes bias to interpretation groundwater ages. It was found that the effects of such errors on the mean transit times and young water fractions can be minimised through careful selection of compound lumped parameter models, based on hydrologically and geologically validated information. Model selection can be assisted by repeated tritium measurements. Aggregation errors due to mixing of water from different flow paths is a fundamental groundwater issue, applying to all measured tracer concentrations including age tracers, isotopes, and chemistry.

Stewart MK, Morgenstern U, Gusyev MA, Maloszewski P. 2016. Aggregation effects on tritium-based mean transit times and young water fractions in spatially heterogeneous catchments and groundwater systems, and implications for past and future applications of tritium. Hydrology and earth system sciences discussions. 21: 4615-4627. doi:10.5194/hess-2016-532.

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Output 2.7 Using binary mixing models to address ingress of young water into generally old waters (GWR funded)

Last year’s drinking water contamination at Havelock North’s water supply well demonstrated that, in certain hydrogeologic and pumping situations, young water ingression into generally old groundwater can occur and pose a contamination risk to drinking water supplies. This is an issue for other New Zealand water supplies and needed an urgent solution. Binary mixing models, with parameter calibration via multi-age-tracer time series, can address this issue. This is a new interpretation approach not yet dealt with in the New Zealand Drinking Water Standards.

Morgenstern U, Stewart MK. 2017. Calibrating binary lumped parameter models [abstract]. In: European Geosciences Union General Assembly; 2017 April 23-28; Vienna, Austria. Goettingen (DE): Copernicus Gesellschaft. EGU2017-11370. (Geophysical research abstracts; 19).

Output 2.8 Further radon applications to identify groundwater discharge locations and fluxes (GWR, multiple regional authorities, co-funded)

Our newly developed radon technique has provided increased detail of groundwater-surface water interaction in New Zealand hydrological systems. Radon identifies locations of groundwater discharge, which enables better estimations of groundwater flux. It was not possible to obtain this detail of information from conventional hydrological techniques in the same timeframe or budget. This knowledge is essential for building realistic conceptual groundwater flow models. To date, the radon technique has featured in several regional studies, in collaboration with: Environment Canterbury, Environment Southland, Gisborne District Council, and Bay of Plenty, Hawke’s Bay, Horizons, Otago, Taranaki and Great Wellington regional councils. Understanding how surface- and ground-waters interact is integral for the successful management of groundwater nutrient inputs to surface water ways.

Martindale H, Morgenstern U, Singh R, Stewart B. 2016. Mapping groundwater-surface water interaction using radon-222 in gravel-bed rivers: a comparative study with differential flow gauging, Journal of Hydrology (NZ), 55 (2): 121-134. Morgenstern U, Begg JG, van der Raaij RW, Moreau M, Martindale H, Daughney C, Franzblau R, Stewart M, Knowling M., Toews M, Trompetter V, et al. 2017. Heretaunga Plains Aquifers: Groundwater Dynamics, Source and Hydrochemical Processes as Inferred from Age and Chemistry Tracer Data. Lower Hutt (NZ): GNS Science. 50 p. (GNS Science report; 2017/33).

Output 2.9 Combined age tracer interpretation reveals regional groundwater processes (GWR, Horizons Regional Council, co-funded)

New insights into regional groundwater processes in the Wanganui-Manawatu region were gained thanks to a comprehensive interpretation of age and isotope tracer data. Insights included refined assessments of the age of water, groundwater recharge characteristics, transport mechanisms, interactions with surface water, and potential denitrification occurring in the subsurface. These interpretations are pioneering in both the New Zealand and international contexts. This information will be used by Horizons Regional Council to assess the effectiveness of their monitoring networks against the requirements of the Regional Policy Statement, Regional Plan (One Plan) and the National Policy Statement for Freshwater Management. Morgenstern U, van der Raaij R, Martindale H, Toews M, Stewart M, Matthews A, Trompetter V, Townsend D. 2017. Groundwater dynamics, source, and hydrochemical processes as inferred from Horizon’s Regional Age Tracer Data. Lower Hutt (NZ): GNS Science. 63 p (GNS Science report; 2017/15). doi: 10.21420/G2J596.

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Output 2.10 National Tracer Survey (GWR) The National Tracer Survey collects age-tracer data in data-sparse areas of New Zealand. The objective is to create long-term age tracer to improve calibration of water age models. This year, age tracer samples for this purpose were collected in Taranaki, Gisborne and Marlborough.

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RQ3. What are the fluxes of key substances into, out of and through New Zealand's aquifers?

Output 3.1 National groundwater quality monitoring (NGMP funded)

The national network presently consists of 110 active sites (Figure 3.1). Well O31/0156 (Canterbury region) was discontinued following a post-Kaikoura earthquake inspection, suggesting issues with the well integrity (gas burn holes in casing).

Modifications were implemented to monitoring operations between December and June 2016 in response to samples received at temperatures above those recommended by the national groundwater sampling protocol during the March and June 2016 sampling events. The modification process was consultative and benefited from constructive suggestions from the regional council teams. Implementation was smooth and effective (more than 90% of the March 2017 samples were received at acceptable temperatures). Effected changes included: the introduction of a chain of custody form to comply with standard sample handling requirements and, as a measure to reduce sample handling and transport issues (e.g., high temperatures, partial filling of bottles); field form update to record calibration procedure and results, as well as the sampling protocol (paper and digital forms were updated) and handling optimisation (analyses are now managed by the laboratory) to reduce the delay in releasing the final analysis. This upgrade also increased synergies between NGMP and SOE sampling by accounting for the isolation of some NGMP sites and introducing more sampling kits where needed.

Groundwater quality data collected as part of NGMP can be accessed through the Geothermal and Groundwater database. Access to NGMP data using a Sensor-Observation-Service, in Groundwater Markup Language 2 (GWML2) format is currently being tested.

Figure 3.1: NGMP site locations.

Geothermal and GroundWater Database. 2017– Release 3.1.0. Lower Hutt (NZ): GNS Science. [updated 2017Nov14; accessed 2017Nov14]. https://ggw.gns.cri.nz/ggwdata.

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Output 3.2 Baseline trends for New Zealand groundwaters using a machine-learning- augmented dataset (NGMP funded)

How rapidly does groundwater chemistry change in the absence of human influence? Following a study from 2006, which was based solely on NGMP data, this new work used machine-learning techniques to include the regional state-of-the-environment monitoring datasets. Baselines for rates of change (trends) were derived at 234 sites (100 sites from the NGMP network) for 13 parameters for the 2005-2015 period and could be used as benchmarks to use when assessing temporal trends in groundwater quality.

Moreau M, Daughney C. Forthcoming 2017. Setting national baselines for groundwater quality trends using multi-variate statistics applied to a machine-learning-augmented dataset. In: New Zealand Hydrological Society Annual Conference; 2017 Nov 28-Dec 1; Napier, New Zealand. Wellington (NZ): New Zealand Hydrological Society.

Output 3.3 First regional groundwater baseline survey for emerging organic contaminants in preparation (GNS Science SSIF, British Geological Survey, Waikato Regional Council, co-funded)

Overseas studies have shown that many different types of emerging organic contaminants (EOCs) are present in groundwaters and surface waters. However, despite growing international concern, there have been no assessments of the occurrence of EOCs in New Zealand groundwaters. This collaborative project aims to perform a pilot assessment of the occurrences, types and concentrations of a wide range of EOCs in New Zealand groundwater. As part of this project, training with EOC experts (British Geological Survey) was completed in September at their Wallingford, UK office. Training included: field sampling, laboratory processing, sampling design, data QC and a visit to the National Laboratory Service (NLS). EOC samples are tested at NLS, as part of routine monitoring by the UK Environment Agency, for a suite of more than 700 EOCs, an analytical capability currently unmatched by New Zealand laboratories.

The next phase comprises a groundwater baseline EOC survey in the Waikato region. New Zealand samples will be analysed at NLS. If EOCs are found to be an issue, this work will identify what types and forms of EOCs are of greatest concern and design a strategy and funding mechanism for future monitoring of EOCs in groundwater.

White D, Williams PJ, Civil W, Lapworth DJ. 2017. A field based method for pre-concentration of micro organics using solid phase extraction. Keyworth, Nottingham (UK). 21 p. (British Geological Survey Open Report; OR/17/011). Lapworth DJ, Baran N, Stuart ME, Ward RS. 2012. Emerging organic contaminants in groundwater: A review of sources, fate and occurrence. Environmental Pollution 163: 287-303. doi: https://doi.org/10.1016/j.envpol.2011.12.034.

Output 3.4 Groundwater transport modelling for pathogens (ESR funded)

GNS Science is providing input to four groundwater transport modelling programmes that focus on pathogen transport and land use based nitrate contamination. These include: (i) the use of the facies modelling software T-progs in fine scale pathogen transport risk assessments; (ii) upscaling fine scale pathogen transport models, and the errors associated with different upscaling methods; (iii) land use based nitrate transport in the Mid-Mataura valley; and (iv) virus pathogen transport in New Zealand aquifers. Four manuscripts describing these studies have been drafted and are currently being finalised. This work is also relevant to RQ2.

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RQ4. How have/will human activities, climate change and other pressures affect New Zealand's groundwater resources?

Output 4.1 Modelling the impact of sea-level rise in the Heretaunga Plains (GNS Science SSIF, GWR, co-funded)

Potential impacts of sea-level rise (SLR) in the Heretaunga Plains (Hawke’s Bay) include salinisation of the heavily relied-upon groundwater resources in the plains through both seawater intrusion and land-surface inundation processes. This project assessed these risks using a modified version of a recently developed groundwater-flow model of the Heretaunga Plains (by Hawke’s Bay Regional Council and GNS Science). Density-dependent groundwater flow and transport simulations were conducted to predict the relative movement in the seawater/freshwater interface location under a series of recent SLR projections and water management scenarios. A rudimentary assessment of the land-surface inundation effects in terms of salinisation through vertical leakage was also undertaken.

Rotzoll K, Fletcher CH. 2013. Assessment of groundwater inundation as a consequence of sea-level rise. Nature climate. change 3: 477-481. doi:10.1038/nclimate1725.

Output 4.2 Changes in pasture production under climate change scenarios (GWR funded)

The projected impact of climate change on New Zealand’s national pasture production was modelled, as previously reported. This work contributed to two additional publications in 2016- 17 as part of the Climate Change Impacts and Implications project: a national synthesis report, and a case study on the Upper Waitaki catchment.

Ausseil AGE, Bodmin K, Daigneault A, Teixeira E, Keller ED, Baisden T, Kirschbaum MUF, Timar L, Dunningham A, Zammit, et al. 2017. Climate Change Impacts and Implications for New Zealand to 2100: Synthesis report RA2 lowland case study. IN: Climate Change Impacts and Implications for New Zealand to 2100. MBIE contract C01X1225, Wellington (NZ). 60 p. (Synthesis Report LC2714).

Output 4.3 Theoretical foundation for the model stream lining (SAM funded)

Methods to assess how to effectively streamline models to improve the decision-making processes employed in groundwater management are being developed. This includes provision of metrics for assessing which data-model combination best supports the decision- making process. A draft discussion paper outlining the background mathematical theory for the SAM programme was completed in June 2017 and circulated to stakeholders; research collaborators, and the wider research community (via a workshop sponsored by the Australian National Centre for Groundwater Research and Training; and a plenary session for the 2017 Australasian Groundwater Conference, Sydney). For wider readership, a summary document was prepared in July 2017 and circulated through several Australian government environmental organisations. The draft discussion paper “A theoretical analysis of model simplification” and the summary document “Simple is Beautiful” are freely accessible through the GNS Science website. These outputs are also relevant to RQs 1, 2, 3 and 5.

Doherty J, Moore C. 2017. Simple is Beautiful [white paper]. GNS Science website. url: https://www.gns.cri.nz/content/download/12756/67966/file/Simple is beautifulv3.pdf. Doherty J, Moore C. 2017. A theoretical analysis of model simplification [white paper]. GNS Science website. url: https://www.gns.cri.nz/content/download/12626/67254/file/GNS_SAM_project_draft_ discussion_paper.docx.

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Output 4.4 Decision focus for model simplification (SAM) A report has been published that documents and summarises the collation and identification of community and stakeholder freshwater objectives, issues and questions for each of the three SAM case study catchments. This summary provides the basis for the design of specific resource management decision-based scenarios to be tested in the SAM programme. SAM programme scientists are currently working with regional council staff to define and finalise appropriate model questions, in relation to freshwater issues identified in this report, which will be implemented in the case study catchments. The Decision Variables report is freely accessible through the GNS Science website. This output is also relevant to RQs 1, 2, 3 and 5.

Lovett A, Moore C, Zammit C, Elliot S, Jackson B., McDonald G. Forthcoming 2017. Translating resource management decisions into modelling. In: New Zealand Hydrological Society Annual Conference; 2017 Nov 28-Dec 1; Napier, New Zealand. Wellington (NZ): New Zealand Hydrological Society. Lovett A, Gyopari M, Moreau M, Moore C, White P. 2017. Resource management decisions and data requirements to support the SAM research programme. Lower Hutt (NZ): GNS Science. 30 p. (GNS Science report; 2017/19). url: http://shop.gns.cri.nz/sr_2017_019-draft-pdf/.

Output 4.5 Development of synthetic models for SAM (Watermark Numerical Computing, Flinders University, Australian National Centre for Groundwater Research and Training, co-funded)

Two synthetic models are currently being developed and applied within SAM as a basis for investigating the effectiveness of model simplification strategies. The first model will be used to demonstrate and test methods that embody the theoretical framework described above (Output 4.3). The second model will be used as the basis of a whole programme suite of numerical experiments. The second model utilises the HydroGeoSphere simulation software, which fully incorporates the complexity of both surface and groundwater modelling (Figure 4.1). This output is also relevant to RQ1, 2, 3, 5.

Figure 4.1: A schematic of the second SAM synthetic model. The model represents a 1,476 km2 hypothetical hillslope catchment featuring a stream network discharging to a freshwater lake, with a range of land use types (e.g., dairy) and public water-supply wells. The left plot shows simulated uppermost subsurface-domain saturation; the right plot shows surface-domain water depth overlain with log- velocity vectors. Moore C, Doherty J. Forthcoming 2017. Metrics for simplification in the decision-making context. In: New Zealand Hydrological Society Annual Conference; 2017 Nov 28-Dec 1; Napier, New Zealand. Wellington (NZ): New Zealand Hydrological Society.

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Output 4.6 Stream lined models to assess water and land use management issues and the limit setting process, three case studies (SAM, Greater Wellington Regional Council, Waikato Regional Council, Environment Southland, co- funded)

The SAM programme is also focussing on three regional case studies, in the Ruamahanga Valley, the Hauraki Plains and the Mid-Mataura -Waimea groundwater zones. Each of these case studies focusses on the development of stream-lined models to assess water and land use management issues, and the limit setting process under the National Policy Statement for Freshwater Management. In addition, the following catchment modelling software packages are being extended as part of this programme with our research partners: LUCI (Victoria University of Wellington), CLUES-GW and TOPNET-GW (NIWA).

GNS Science has been developing several streamlined surface water-groundwater model versions, which will be tested within the theoretical framework outlined above. ESR has also been defining the spatial distribution of redox potential within each of these case study areas, and examining the uncertainty associated with these estimates. The University of Waikato is assessing the impact of surface and groundwater flux uncertainties in time and space on a lake model (Lake Wairarapa). NIWA is assessing the impact of surface water flow uncertainties on the modelling of ecological habitat in the Mid-Mataura case study. Market Economics is assessing the impact of surface and groundwater flux uncertainties in time and space on economic model outputs for both the synthetic model and the Hauraki case study. This involves constructing a farm systems model, coupling the economic and farm systems model and incorporating the uncertainty component into the current economic module.

These models (lake, ecological and economic) are also assessing the total uncertainty of their model outputs, so that the contribution to this uncertainty from surface water and groundwater models can be assessed within the wider total uncertainty context. This output is also relevant to RQs 1, 2, 3 and 5.

Output 4.7 Commercial regional flow and transport modelling work (regional authorities funded)

Four sub-regional groundwater models were contracted, developed and calibrated for the following areas: Waimakariri-Ashley Plains, Ruamahanga Valley, Hauraki Plains, and the Heretaunga Plains. All four of these models simulated groundwater flow and nitrate transport and were contracted by regional councils. For two of these models, model development was undertaken in very close collaboration with council staff with weekly meetings (sometimes daily) used to align efforts (Waimakariri-Ashley Plains model and Heretaunga Plains model). These models were all developed to inform a variety of decisions relating to land- and water- use. For three of these projects, formal uncertainty analyses have also been undertaken to explore all parameter combinations that can also match the observed data. This allows us to quantify the uncertainty associated with model predictions. This is also scheduled to be undertaken for the Hauraki model in future work.

Moore C, Gyopari M, Toews M, Mzila D. 2017. Ruamāhanga Catchment Groundwater Modelling. Lower Hutt (NZ): GNS Science. 189 p. (GNS Science consultancy report; 2016/162). Knowling M, Hayley K, Moore C, Rakowski P, Hemmings B. 2017. Calibration-constrained Monte Carlo uncertainty analysis of groundwater flow and contaminant transport models of the Heretaunga Plains (Hawke’s Bay). Lower Hutt (NZ): GNS Science. In prep. (GNS Science consultancy report; 2017/219). Hemmings B, Moore C, Knowling M, Toews M. 2017. Groundwater flow model calibration for the Waimakariri-Ashley region of the Canterbury Plains. Lower Hutt (NZ): GNS Science. In prep. (GNS Science consultancy report; 2017/221).

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Hemmings B, Moore C, Knowling M, Toews M. 2017. Calibration-constrained Monte Carlo uncertainty analysis of groundwater flow and contaminant transport models for the Waimakariri-Ashley region of the Canterbury Plains. Lower Hutt (NZ): GNS Science. In prep. (GNS Science consultancy report; 2017/222). Moore C, Toews M. 2016. Model development scoping study for the Hauraki Catchment. Lower Hutt (NZ): GNS Science. 33 p. (GNS Science consultancy report; 2016/62).

A modelling study was also contracted by Greater Wellington Regional Council to examine the uncertainties associated with stream depletion estimates in the Ruamahanga Valley. This was a comparison study, where the errors caused by using simpler models such as analytical solutions, were compared with errors involved in using a complex numerical groundwater model. This study is currently being extended as part of the SAM programme, and findings from this extension are being presented at the New Zealand Hydrological Society Conference.

Knowling M, Moore C. Forthcoming 2017. Simple versus complex models for stream depletion confidence limits. In: New Zealand Hydrological Society Annual Conference; 2017 Nov 28-Dec 1; Napier, New Zealand. Wellington (NZ): New Zealand Hydrological Society. Knowling M, Moore C. 2017. Assessment of stream depletion calculation confidence limits. Lower Hutt (NZ): GNS Science. In prep. (GNS Science consultancy report; 2017/145).

Output 4.8 Satellite data for wetland dynamics (GNS Science SSIF funded)

Recent satellite studies have yielded novel information on water dynamics. However, these studies are mostly global and don’t incorporate the wealth of novel global environmental satellite data, e.g., high resolution satellite radar and optical data from the European Sentinel satellites. Furthermore, these studies only show the net change over a 30-yr period, and do not show short-term or seasonal changes. Therefore, a demonstrator that can measure wetland dynamics over all of New Zealand using Sentinel-1 and -2 data was developed. Its application to view near real-time information of flood extents, both for large flood plains, or smaller flooded rural areas, was explored in collaboration with Waikato Regional Council (Figure 4.2) and presented to four other regional councils.

Figure 4.2: Google Earth Engine image analyses from some wetlands in Waikato Region. Left: Classification of vegetation type in Lake Whangape wetlands based on Sentinel-1 radar and Sentinel-2 multi-spectral satellite data. Right: flooding in the Kopuatai Peat Dome and Waihou River on 16 April, based on Sentinel-1 radar data.

Westerhoff R, Tschritter C. Forthcoming 2017. Satellite observation of wetland dynamics and recent flood events using Google cloud-computing services. In: New Zealand Hydrological Society Annual Conference; 2017 Nov 28-Dec 1; Napier, New Zealand. Wellington (NZ): New Zealand Hydrological Society.

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Output 4.9 Assessment of water source and contaminant pathways in the Waiokura catchment using hydrochemical and isotopic methods (GWR and Taranaki Regional Council, co-funded)

A collaborative project to improve understanding of nutrient loads from groundwater to the spring-fed Waiokura Stream was carried out. This project is developing a targeted suite of hydrochemical and isotopic tracers for selected surface water and groundwater sites to inform flow paths, and origin of water and contaminants (N and P). The hydrochemical suite includes 18 2 stable isotopes of water (oxygen-18 (δ O-H2O), deuterium (δ H-H2O)), nitrogen-15 and 15 18 oxygen-18 of NO3 (δ N-NO3, δ O-NO3), hydrochemistry (Cl, Br, Na, Ca, Mg, K, Alkalinity, DOC, SO4 N, P and SiO2) and age tracer data at ground and surface water sites in the Waiokura catchment, Taranaki. Used in conjunction with physical flow measurements the hydrochemical suite provides a powerful tool for discriminating water origin.

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RQ5. How can we ensure that stakeholders will use our research results appropriately and efficiently?

Output 5.1 Knowledge transfer / outreach

Table 5.1 summarises the workshops to which we contributed this year. We have also been involved in several workshops to help guide model development, with Environment Canterbury and Hawke’s Bay Regional Council (Catherine Moore and Paul White). As part of the collaborative modelling approaches undertaken on the Environment Canterbury and Hawke’s Bay Regional Council projects, there has been aspects of training and upskilling of regional council staff.

Table 5.2 summarises outreach activities to which we have contributed to this year.

Table 5.1: Knowledge transfer activities for the July 2016 to October 2017 period.

Related Event Event name GNS Science Event outcome type (organiser – date) programme This event highlights some Ka Tu Te Taniwha – collaborations between Ngā kura huna ā papatūānuku Ka Ora Te Tangata GNS Science and iwi. Ngā Kura (GNS Science – July 2016) Project Huna a Papatūānuku combines workshop (ended Sep. 2016) research, science and matauranga Māori. Ensure effective collaboration and project planning for the drafting of

national standard for discrete water NEMS Discrete Water Quality quality data. Participants include: working group technical workshop NGMP GNS Science, NIWA, Horizons

workshop (NIWA – August 2016) Regional Council, Marlborough District Council, Bay of Plenty Regional Council, Hills Laboratories, Auckland Council. The outcome was discussion on current state of knowledge on Taupo Ignimbrite deposits.

Taupo ignimbrite This was followed by an evening - public Hochstetter lecture (GNS Science – August 2016)

workshop (New Zealand geological Society) given by Colin Wilson at the Great Lake Centre, Taupo and attended by approximately 160 people. Presentation of projects results and provision of technical advice on the use of tracer techniques for the Regional groundwater dynamics coastal lakes monitoring programme. and Groundwater dynamics in the Presented projects aimed to Horowhenua, technical workshop GWR understand land use impact on

workshop (Horizons Regional Council – freshwater quality through improved September 2016) knowledge of nutrient flow pathways between land and water resources, and nitrate attenuation processes.

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Related Event Event name GNS Science Event outcome type (organiser – date) programme The workshop was attended by MfE and the NGMP working group from the Groundwater Forum. Four possible new research directions

were discussed and all were NGMP research and operations received favourably without a review GWR/NGMP preference. The workshop identified

workshop (GNS Science – October 2016) that by undertaking groundwater quality pilot surveys and providing guidance on best-practices and interpretation methods, NGMP has been used to steer water management. This talk summarised the 2000

Walkerton E.coli severe outbreak (7 Walkerton 2000: lessons for deaths; 2,300 affected people with New Zealand? - ensuing long-term effects) including

workshop (GNS Science – December 2016) crisis response and health effects and implications for water supply in Canada. The one-day workshop was attended by programme members from

GNS Science, NIWA, ESR, VUW, Market Economics, Land Water Annual technical workshop SAM People, and Earth in Mind. The (GNS Science – March 2017)

workshop purpose of the workshop was to ensure effective collaboration and project planning for the continuation of the programme (2016-2019). The workshop was attended by Environment Canterbury (Ecan), Christchurch City Council (CCC), and GNS Science staff. Key

outcomes of the workshop were that Christchurch Aquifer Study age dating required for CCC Drinking technical workshop Water Security and ECan (Environment Canterbury –

workshop ‘groundwater management’ April 2017) purposes would also be beneficial to improve understanding of water movement within deep GW systems, such as the Christchurch aquifer system.

Technical training of two Leapfrog GWR Environment Southland staff course

training training (GNS Science – June 2017) members and a contractor.

Tutaekuri, Ahuriri, Ngaruroro and Presentation of the latest findings on

Karamu groundwater drinking water security GWR

public (Hawke’s Bay Regional Council – and groundwater dynamics in the meeting June 2017) Heretaunga Plains.

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Table 5.2: Outreach activities for the July 2016 to October 2017 period.

Related Event name GNS Science Event outcome (organiser – date) programme

Science Evening Overview of the ‘greater’ Lake Tarawera catchment (Bay of Plenty Regional groundwater and land use. Council – September 2016)

Presentation of work to understand contributions of Episode 5 of ‘Coast aquifer pressure to liquefaction. Displays included New Zealand’ Royal Society of material from a drill core and skyward flow of (TV One – screened New Zealand groundwater from an artesian well. The episode and 22 May 2017) Marsden Fund highlighted how aquifer pressure is strongly correlated Watch it here to liquefaction damage.

MBIE Curious Minds, Otago Series of lectures on the “Geological History of South What lies beneath – the Regional Council, Dunedin”, teaching children how to drill auger holes, changing ground environment New Zealand observe the subsurface sediment and install in South Dunedin International groundwater monitoring equipment. Science Festival

Output 5.2 Continued contribution to the development of national and international standards (GWR funded)

GNS Science continues to be a strong contributor at workshops on developing National Environmental Monitoring Standards (NEMS) for discrete water quality sampling; data transfer in New Zealand, and GWML2. The NEMS discrete water quality sampling is now open for public review, until December the 6th. To download and submit a review please visit this link: http://www.nems.org.nz/documents/water-quality-part-1-groundwater/

Output 5.3 Consolidating metadata of our national datasets (NGMP funded)

Data management plans for NGMP data are currently being drafted. A management plan and associated risk register provides a high-level overview of the dataset, the resourcing plan, dataset architecture and structure, risks and future enhancements. The procedure document clarifies the data workflow and associated responsibilities to ensure the quality of a dataset. It includes information on where to find published reviews, QA/QC procedures and QA/QC records.

Although QA/QC procedures have been in place for years, it is the first time that these are centrally documented. It is an important step towards achieving transparency in data management for this national dataset. This process also allowed review of the QA system with a broad perspective and resulted in the addition of one check to ensure that throughout the data workflow, a two-people check process is in place as recommended per NEMS standards. This work also includes implementation of a quality code system.

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Output 5.4 Web-accessible groundwater resources (GWR, SAC, NGMP funded) Table 5.3 summarises our public, web-accessible, groundwater resources. Click on the resource name or its thumbnail image to access/download.

Table 5.3: Web-accessible, public, groundwater resources available via the GNS Science website.

Resource Output Description Version: release date type format

Dataset Aquifer Potential Map Version 1.0: 2016 These data/maps are novel for New Zealand and are the first national hydrogeological assessment of New Zealand's QMAP geological shp, database. Datasets used to compile these maps include the New Zealand pdf 1:250,000 geological map (QMAP) lithological and chrono-stratigraphic information (i.e., main rock type; geological age; and secondary rock type).

Geothermal and GroundWater database Version 3.1: 2016 Oracle database containing five public datasets (NGMP, Air Particulate Matter, Volcano monitoring, Bay of Plenty Regional Council Geothermal Database Surface Features and the Hydrochemistry of the Lake Rotorua Catchment), with quarterly updates of the NGMP dataset. The restricted- access State of the Environment dataset was updated last year to include 181,165 individual results for selected parameters. The entire dataset currently contains 68,365 samples and 708,695 individual results. All pdf, regional datasets extend to 2014. csv, xls Development update:

New features – query tool (all users) enabling bulk data retrieval and multi filter search (map selection; project, feature, sample data and analytical parameter filters). This added functionality introduces new data extracts

(feature purpose, feature threats, cross-tabulated analysis results with field and lab data on a single row). In testing – access to NGMP data using a Sensor-Observation-Service, in GWML2 format. In development – implementation of Quality Codes.

Groundwater sample form Version 3.0: 2016 Mobile application Mobile app. to record NGMP sample field measurements with the Fulcrum mobile application platform to streamline field data upload to the GNS Science Geothermal and Groundwater database. Fulcrum allows you - to enter data on your phone or tablet then upload the data to GNS Science when network connectivity is available. To download and install the free app, simply open the Google Play Store (Android) or iTunes store

(iPad/iPhone) on your phone or tablet, search for ‘Fulcrum’ and install it

Website + mobile app Earth Beneath Our Feet Version 4.0: 2016 This website provides free online access to seven sub-regional three- dimensional (3D) geological models. This website is also accessible jpg through a smartphone app. Models are available for the Bay of Plenty (developed for Bay of Plenty Regional Council, updated 2015-16) and the Heretaunga Plains (developed for Hawke’s Bay Regional Council 2014).

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Resource Output Description Version: release date type format

Groundwater Hub Pending release Data portal Interactive scientific data hub and research dissemination platform. The hub is built on cloud technologies, uses Open Geospatial Consortium standard formats and allows on-demand scaling for anticipated increasing data volume and user numbers. The hub uses catalogues from GNS Science (including SAC and NGMP), Land Information New Zealand, NIWA, New Zealand Journal of Hydrology, and MfE, and enables access to real-time data through a Sensor-Observation-Service (52North). The link to this resource will be published on the Database and tool GNS Science webpage. Development update: In testing – User functionalities; automatically generated keyword, access to NGMP data using a Sensor-Observation-Service.

Data portal

Awahou web-portal Version 1.0: 2016 Scientific and Mātauranga-a-iwi water related information (datasets and pdf reports) for Taniwha Springs and the Awahou Stream.

Tool Calculator Version 8.0: 2015 Excel-based spreadsheet for calculating water quality and descriptive xls statistics, and perform trend analysis. Application of this tool is limited to non-commercial use

Tool Simple methods Version 1.0: 2014 Excel-based visualisation tool to assess the relative size of capture zone xls delineations using the simple methods (calculated fixed radius, uniform flow equation).

Tool Capture zone toolkit Version 1.0: 2014 GIS-based capture zone delineation toolkit to automatically delineate well shp capture zone using either the calculated fixed radius or the uniform flow py equation methods. This tool is available either as ready to use (ArcGIS toolbox) or as source code (Python).

Page 25 of 26 GNS Science APPENDIX 1: RELATIONSHIPS BETWEEN GNS SCIENCE HYDROGEOLOGY RESEARCH QUESTIONS (RQs) AND GROUNDWATER FORUM (GWF) PRIORITY RESEARCH AREAS

“Direct“ indicates that the answer to the GNS Science RQs is essential to address a GWF critical research issue. “Indirect” indicates where the answer to the GNS Science RQs brings some elements to address a GWF priority research area.

GNS Science Research programmes

GWR NGMP

SAM VM-P VM-K GNS Science Key Research Questions MGD NHP SAC

Groundwater Forum Research Areas 1.What are the hydrogeological and structural characteristicsNZ's of aquifer systems? 2.What are the fluxes of water into, out ofand through NZ's aquifers? 3.What are the fluxes of key substances into, out ofand through NZ's aquifers? have/will human activities,4.How climate change and other pressures affect New Zealand's groundwater resources? 5.How can we ensure that stakeholders willresearch our use results appropriatelyefficiently? and Drinking water security Direct Direct Direct Direct Direct Advanced work on pathogen survival rates in groundwater and the suitability of the faecal indicator bacteria for prediction of pathogen risk; research and development into smart tools for delineation of source protection zones and aquifer recharge areas; follow-up from the Havelock North enquiry e.g., secure groundwater classification; freshwater quality; assessment of concentrations and effects of emerging contaminants on groundwater quality in New Zealand and implications for connected waters; groundwater contribution to contaminant (bacteria and nutrient) loads in surface waters and smart monitoring tools. Water availability Direct Direct Indirect Direct Direct Quantifying contribution to groundwater from braided rivers; effects of groundwater abstraction on surface water in-stream values; exploring new groundwater allocation methods; establishing sustainable groundwater allocation limits. Indirect Indirect Indirect Indirect Indirect Climate change Climate change and groundwater response, in particular saline intrusion risk in an environment of rising sea levels

Coastal zone Indirect Direct Indirect Indirect Indirect Water quality - effects of changes in groundwater quality on transitional coastal waters and their ecosystems. Water quantity – how to quantify offshore groundwater flow. Groundwater biodiversity Indirect Direct Indirect Direct Direct Biodiversity and ecosystem services to inform freshwater and land management; stocktake of knowledge around groundwater stygofauna; establishing ecologically-sustainable nutrient allocation and establishing the time lag to reverse adverse nutrient effect Direct Indirect Indirect Indirect Direct Natural hazards e.g., liquefaction/groundwater flooding; groundwater level response to earthquakes/resilience in water supplies.

Water quality Direct Indirect Direct Direct Direct Establishing the transport and fate of nutrients and pathogens in a variety of groundwater and hydraulically-connected surface water environments; vulnerability of groundwater and supply bores to land use, setting water quality baselines or reference states. Hydrocarbons Making good management decisions around abstraction of hydrocarbons.

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