After being unable to find viable locations for above-ground water storage in the district, the Hawke’s Bay Regional Council is focusing its water security programme on below-ground MAR options.
Council regional water security programme director Tom Skerman says a MAR pre-feasibility assessment was done early last year.
It indicated that there were grounds to run a field pilot to test how effectively it could work in CHB and to familiarise the community with the concept.
Since then, further work has been undertaken to narrow down areas where pilot sites could best be located. That recently involved ground truthing to narrow down the most promising options.
Skerman says the next step will be to see whether landowners are willing to be a part of the trial and then shortlist the options for advanced technical investigations.
“(If all goes) well, we would like to be in a position to have a trial up and running by next winter,” he said.
“It is likely to need to run for a couple of years to produce the results and data we need to determine whether the technology will work.”
He says it’s likely that water for the pilot will be drawn from rivers or streams nearby, with the volumes necessary relatively modest.
“Everything we do in relation to the pilot will have to be consented in keeping with our own take and discharge regulations and requirements,” he said.
The council will utilise the expertise of the managers of the Gisborne MAR trial once that finishes, while it also plans to have discussions with representatives of MAR projects in Mid-Canterbury and Southland.
Skerman says there is no silver bullet for Hawke’s Bay’s water challenges.
“Every possible option is now being considered, from below-ground managed aquifer recharge, to above-ground storage where it can work, to water conservation, alternative farming systems and land use change,” he said.
The Gisborne trial, which is due to finish at the end of the year, injects water from the Waipaoa River into the Makauri aquifer for use on 3000 hectares of irrigated horticultural farmland.
It’s goal is to see whether it’s possible to increase water in the aquifer with minimal impact on water quality and the environment.
This year’s injection season, which began mid-May, is due to finish this month. Testing involves injecting up to 75,000 cubic metres of water a season into the aquifer.
The Gisborne District Council has approached three independent experts to review data collected, with a report expected in January.
Earlier this year, the Hinds MAR project in Mid-Canterbury received $950,000 from the Provincial Growth Fund to complete feasibility and pilot work, while the Oreti MAR project received just under $600,000 from the same fund last year to explore groundwater storage options in Southland.