Waimakariri zone committee chairman and farmer David Ashby talks about progress on the Waimakariri sub-regional plan and action to improve local waterways.
I recently met a friend, the owner of a small block, who is concerned about the impact of irrigation and dairy farming on the environment.
Specifically he wants to see the Ashley River flowing year-round and in better condition for kayaking and fishing.
He asked me what the zone committee and farmers are doing to improve Waimakariri’s water quality.
The Ashley River has no large irrigation schemes and only a few farmers with relatively small irrigation takes linked to surface water flows. We’ll be working with farmers in the lower Ashley River with hydraulically linked wells as part of the solutions package.
Recent dry years and a build-up of shingle and woody weeds have decreased the flow of the Ashley River. There’s no easy fix: storage is possible but this involves environmental considerations and increased cost.
The Eyre management area which feeds into Silverstream has serious issues and will likely require large cuts in nitrate levels.
Nine test wells have been drilled alongside the Waimakariri River and we’ve taken samples from 180 wells to investigate water quality and groundwater flows. We’ll have this data in early 2018.
While we’re waiting for this information, we’re concentrating on farm environment plans (FEPs) for farmers who belong to Waimakariri Irrigation Limited (WIL) and those outside the scheme who require resource consent to farm.
All farmers within WIL have completed farm environment plans and audits. Their resource consent requires shareholders to maintain at least an audit grade B.
Farm environment plans identify waterways and biodiversity, riparian setback, critical point source areas and cultural values. The audit process helps farmers make required changes to improve water quality.
On farms with heavy soils, nitrates aren’t the problem; instead sediment, phosphorous, E coli and pathogens are causing issues. Plan Change 4 has tools to fix these problems, including stock exclusion, which is a statutory requirement for everyone.
Good management practice will fix 90% of Waimakariri’s issues on all properties regardless of their size. This includes irrigation management, such as the justified irrigation project initiated by the Cust main drain water user group. This project focuses on soil moisture monitoring, pasture growth, fertiliser, effluent use and profitability.
We’re also investigating other solutions including targeted stream augmentation, managed aquifer recharge and an ESR-led denitrification wall trial. Our ‘First 500’ project will protect the first 500m around springheads.
Waimakariri’s blooming urban and peri-urban growth is also impacting our water. We’ve started a programme for small block owners to discuss land use, lifestyle block management plans and Environment Canterbury’s farm portal.
Water quality is everybody’s problem and we’re all part of the solution. Instead of playing the blame game, we need to live above the line and work together to achieve positive change.
