1. Managed Aquifer Recharge Programme Information
Hinds/Hekeao Catchment (Canterbury)
Managed Aquifer Recharge Programme Information
Bob Bower, Principal Hydrologist
RDR Klondyke Storage Consent Hearing
15th February :40 pm

2. What is Managed Aquifer Recharge?
A set of physical tools designed to intentionally recharge water into an aquifer for economic, environmental, social, and culture benefits.

3. 2nd April 2018
~400,000,000 m3/year 2017 of recharge
Restoring groundwater levels for springs and baseflows to river
Increase reliability of groundwater bores

4. National MAR Pilot Projects
Gisborne MAR Pilot
Hinds/Hekeao Groundwater Replenishment Scheme
Southland MAR Pilot

5. Managed Aquifer Recharge
Tools of Integrated Water Management

6. Groundwater Replenishment Scheme
The Bigger Picture
Catchment-scale, conjunctive, sustainable groundwater management.
Tools of MAR
Groundwater Replenishment Scheme

7. Hinds Catchment Between Rangitata and Ashburton Rivers HINDS RIVER
VALETTA
MAYFIELD HINDS

8. Hinds/Hekeao Catchment Approach
Economics
March 2014

9. (Scott, 2013)

10. BALANCING GROUNDWATER: QUANTITY & QUALITY
ADDITIONAL YIELD
ADDITIONAL MAR
ADDITIONAL ALLOCATION
SUSTAINABLE YIELD
MAR
OVER ALLOCATION
ABSTRACTION
Nutrient Leaching Increases
“LOSSES’ IRRIGATION & OPEN RACES
NATURAL YIELD
RAINFALL
GROUNDWATER OUTFLOW
EVAPORATION
RIVER & STREAMS
BASEFLOWS TO SPRINGS AND RIVERS
RECHARGE
DISCHARGE
NATURAL GROUNDWATER STORAGE
DECLINING STORAGE & SPRING FLOWS
MANAGED STORAGE
INCREASING STORAGE & BASEFLOWS
Golder 2017, Hinds Managed Aquifer Recharge Pilot Trial: Phase 1 Report

11. Depth to Groundwater (m)
Changing dynamic groundwater storage
DEPTH OF BORE LEVELS (K37/0300 – GWE-4) -5
-10
-15
-20
-25
WETTER SEASONS
Depth to Groundwater (m)
DROUGHT SEASONS
IRRIGATION & STOCKWATER EFFICIENCIES + GROUNDWATER USAGE
DROUGHT SEASONS
-22.8m
1973
1975
1977
1979
1981
1983
1985
1987
1989
1991
1993
1995
1997
1999
2001
2003
2005
2007
2009
2012
2014
2016
Time

12. 36 Spring-fed streams and Hinds River
Over 230 km of streams and groundwater dependent ecosystem habitat
Cultural Values including Mahinga Kai sites (HDWP)
Threatened Aquatic and Endangered Species
Until recently strongholds for native and non-native species

13. Average Annual Nitrate-Nitrogen Concentration (mg/L)
Hinds Catchment – Increasing of Nitrate Levels 12 10 8 6 4 2
Drinking water max accepted value (MAV)
SHALLOW GROUNDWATER
SURFACE WATER DRAINS
Guideline – 80% protection of aquatic biodiversity
Average Annual Nitrate-Nitrogen Concentration (mg/L)
Half MAV average concentration target
Guideline – 90% protection of aquatic biodiversity
DEEP GROUNDWATER
1990
1995
2000
2005
2010
2015

14. MAR Programme: Targeting Drinking Water Benefits
Tinwald High Nitrate Area
MAR Programme: Targeting Drinking Water Benefits
Key Drinking Water Issues
80% of Ashburton Residents take water from rural bores
CDHB reports some of highest rates of enteric diseases (Ashburton District)
Drinking water protection a national concern (E.g. Havelock)
Tynwald Plume targeted my MAR Pilot Trial
6 community supply systems including towns of Hinds, Mayfield and Ashburton

15. Hinds Mitigations QUANTITY QUALITY Cap new groundwater allocations
Review existing permits for actual usage (metering rule)
Community solutions
Allow surface users to transfer to groundwater
Initiate MAR pilot for proof of concept testing
QUALITY
Reduce nitrogen losses at farm level 36% by 2035
Set a groundwater quality target for catchment reached of 6.9 mg/L by 2035
Initiate MAR pilot for proof of concept testing

16. MAR Pilot Testing Site MAR Site final location Higher nitrate plume
MAR testing location background
HINDS RIVER
VALETTA
MAR Site final location
MAYFIELD HINDS
Higher nitrate plume
Most impacted baseflows
Source Map – Golder, 2017

17. Hind/Hekeoa Catchment
Infiltration Basin with Forebay, and Monitoring
MAR SITE BORE
SITE ACCESS GATE
FOREBAY
MAIN INFILTRATION BASIN
MAIN BASIN LEVEL
TIMARU TRACK
FRASERS ROAD
OVERFLOW
BYPASS GATE
MAR SITE BOUNDARY

18. YEAR 1 – WATER QUANTITY AND QUALITY COMPOSITE RESULTS (GWD-4 BORE)5 10 15 20 25 30 10 8 6 4 2
DEPTH TO WATER
Groundwater level as measured from the surface (m)
Nitrate N Concentration (mgN/L)
FIELD MONITORING LAB RESULTS NO3-N
LINCOLN AGRITECH SENSOR NO3-N
27/4/16
17/5/16
6/6/16
16/7/16
5/8/16
4/10/16
26/6/16
25/8/16
14/9/16

19. Year 1 - Results Quantity Quality Site operations
279 Days of operations – 10 June 2016 to 9 June 2017
Year 1 - Results
Increases in groundwater levels approximately 7 km from the Pilot Trial site.
Site operations
2.4 Million m3 of new recharge
8% of Valetta GAZ overallocation
Quality
MAR command area: groundwater nitrate-N values from 14 g/m3 to < 4 g/m3
Improvements in quality for domestic supply bore tested, but much more needed.
Passive soil aquifer treatment (S.A.T.)

20. Developing a Catchment-Scale Groundwater Replenishment Scheme
Current Programme of Works
(2017 to 2019)

21. Prepared for the MAR GG Business Case Workshop
Community Scaled Solutions for Catchment Scale Issues
Hinds GRS Goals
Increase and actively management groundwater storage (levels)
Community scale solutions
Improve water quality in aquifer (springs)
Improve flows and quality in spring-fed streams and rivers for ecological and cultural values
Improve and protect drinking water supplies
What key aspects of the GRS Mission and Goals need to be confirmed for the Business Case?
WGA NZ

22. Prepared for the MAR GG Business Case Workshop
Work Programme
Hinds GRS Programme
Business Case and Master Plan
Community scale solutions
Setting Goals and Programme Milestones
Continuing to develop the MAR Tools through science-based testing and designs
Representative and Accountable Governance
Community input and guidance
Set annual recharge goal 125,000,000 m3 (10 year Goal)
What key aspects of the GRS Mission and Goals need to be confirmed for the Business Case?
WGA NZ

23. New MAR Testing Sites

24. Testing Site Concept Design
Full Utilisation of ADC Unused Stockwater (500 l/s)
MAR Pilot Site currently 113 l/s with enhancement in consenting process (March)
16 sites have been consented up to 50 L/s per site.
12 have been constructed, 3 are currently operating.
Near River Recharge in consenting (up to 200 l/s).
Greater than 500 l/s MAR capacity tested by May 2018.
Testing Site Concept Design

25. COMMUNITY PARTNERSHIPS
Focusing on maintaining strong and diverse partnerships to ensure programme goals are representative of community

26. Christchurch 4 Ash Street, Christchurch Central 8011 Telephone: 029 201 2996
WALLBRIDGE GILBERT AZTEC
Questions?