Rubicon Newsletter – March 2023

Near River Recharge is achieved by clean water sourced via irrigation scheme infrastructure discharged into excavated basins near a river, thus enhancing river flows. 

The large and complex project will eventually include dozens of sites located across 250,000 acres in the New Zealand’s South Island region of Canterbury to enhance the quality and availability of water for the future. 

Rubicon’s part in the overall project is relatively small in scale but of significant importance as the automated control and monitoring infrastructure provided by Rubicon is vital to the success of these MAR projects. Currently, two Rubicon monitoring sites are connected via Rubicon’s software to multiple sensors. There are three powered control sites, three PikoMeters and one SlipMeter – all of which are responsible for ensuring water flow is accurately managed and measured. 

Further potential for Rubicon infrastructure will be during the current development phase of the PROJECT at 25 new or upgraded sites to be mostly controlled by SlipMeters and a further few controlled by PikoMeters or BladeMeters. Eventually there may be as many as 55 Rubicon gates in operation with potential additional uses for Rubicon’s FerIT™ Node and FerIT™ Solar Node for communication purposes.. 

The Hekeao/Hinds projects are attempting to leverage data and technology to improve farming practices of the past that degraded the quality of groundwater. Nitrate-N concentrations in the groundwater vary across the catchment, but in some cases, regularly exceed the New Zealand Drinking Water Standard of 11.3mg/l nitrate-Nitrogen. The New Zealand Government has longer term targets of 2.4mg/l nitrate-N. 

Dr. Brett Painter, representing the Hekeao/Hinds Water Enhancement Trust that is managing the project, explained how the worldwide perception for pristine water  conditions in New Zealand are not always the ‘whole truth’ and that the country must also work towards environmental improvements, just like anywhere else on the globe. 

“We have not always known what is going on in our water systems” said Dr. Painter,  who describes himself as a water systems scientist. “We generally say that New Zealand is cleaner and greener, but we also know it is not green enough.”  

With a PhD in Natural Resources Engineering,  a 17-year history of environmental research and a further 13– years of leading projects, Dr. Painter says the Hekeao/Hinds Projects are an impressive example of how stakeholders have worked together and avoided adversarial situations to make the improvements reality. “We made a safe place for informed discussion and parties demonstrated a lower level of self-interest” he added. 

Pilot projects proved how water contamination could no longer be considered a lost cause and that  improvement techniques work. Local communities, now understanding clearly the advantages of cleaner water and how to reach it, were then able to enthusiastically put plans and funding into action.  The Hekeao /Hinds Water Enhancement Trust was created. 

Nevertheless, Dr. Painter points out that after decades of agricultural land use “it takes a long time to turn the ship around’’. 

The co-ordinated effort also requires farmers to embrace ongoing nutrient management improvements. Current groundwater contains a mixture of nitrate accumulated from recent months to years, and a legacy of issues  brought about over years to decades of land use practices. “It is a long process to make a difference in water quality and associated eco-system health” said Dr. Painter. 

Most of the groundwater has traveled via multiple layers of old braided channels from the historic Rangitata and Ashburton glaciers. While on its journey to the coastal waterways and then the ocean, the pristine water became contaminated by nutrient seepage. 

Dr. Painter explains how some deep aquifer water could take 100 years or more to clean-up, while more shallow aquifer water could take as little as ten years.  

The Hekeao/ Hinds Water Enhancement Projects are designed to speed up that process. Managed Aquifer Recharge is described by the Trust as “an activity that is for the express purpose of improving the quality and/or quantity of water in a receiving groundwater aquifer or a hydraulically connected surface water body.”    

Near River Recharge is described as Managed Aquifer Recharge conducted in the current flood plain of a river system, but not mixing with natural surface water. Pristine water from the Rangitata River is moved directly to recharge sites where all contaminated soil has been removed, therefore allowing the clean water to flow directly into the aquifer. 

Other elements of the solution include an enhanced  habitat for native birds, lizards and fish by planting native forests around key project sites and native aquatic plants in supported wetlands.  

Further information on the project is available at:  www.hhwet.org.nz