Looking back on nine years of the Ashburton Water Zone Committee

David Caygill, outgoing Environment Canterbury representative on the Ashburton W

David Caygill, outgoing Environment Canterbury representative

Nine years ago Environment Canterbury and the Ashburton District Council set up the Ashburton Zone Committee to look at water in Ashburton.

I’ve just stood down as the regional council’s representative on the committee. It’s been a privilege to serve with the other members of the committee.

Achieving targets set by the Canterbury Water Management Strategy

There are 10 Zone Committees in all, covering the whole of Canterbury. They grew out of the Canterbury Water Management Strategy (CWMS), which was agreed in 2009, by Environment Canterbury, the District Councils including Ashburton, Ngai Tahu, Federated Farmers, Irrigation New Zealand, Fish and Game, Royal Forest and Bird and several other organisations.

The Strategy sought to address the host of challenges relating to water that was beginning to pile up. It predated similar efforts by the government, which led to the first Policy Statement for Freshwater Management in 2011.

Essentially the CWMS called for simultaneous action on water quantity and quality, biodiversity, recreational objectives, kaitiakitanga, the special nature of Canterbury’s alpine braided rivers, and the economic and social aspects of water use. In particular, it sought quantity and quality limits for all Canterbury’s rivers, lakes and streams.

The Strategy’s list of challenges and targets was daunting. So much needed to be done. It was also clear that some parts of Canterbury faced quite different conditions from other parts. Not all districts had as much irrigation as Ashburton. Not all had yet switched to dairying. Cities like Christchurch needed to deal with far more stormwater than other centres, as well as the aftermath of the earthquakes.

Focusing on the Ashburton river

Matthew Hall was the first Ashburton chair. He encouraged us to focus first on the Ashburton River, which, unlike most of Canterbury’s rivers at that time, still lacked a flow regime – a rule limiting the point at which irrigators and other users needed to stop drawing from the river or groundwater connected to the river.

Two public meetings later and there was broad community support for abstraction limits that would allow the mouth of the river to be open most of the time.

This would assist fish passage and other forms of recreation such as swimming. It took another year to agree on limits on all the tributaries that fed the Ashburton, but eventually, the Zone Committee made its recommendations to Environment Canterbury.

Public hearings followed, at which the District Council asked for more time to reduce its stockwater take from the river. Eventually, limits were set, applying from 2023 to any new consents. Currently, existing consents are being reviewed so that the same limits will apply to them.

For many, this will mean less reliable irrigation. But that’s the balance that has been struck between the needs of the environment and the impacts of less reliable irrigation. The adjustment to alternatives will take time, just as formulating these new rules has taken time.

Find out more about the Ashburton consent review.

Making a change in the Hinds catchment

A similar exercise in the Hinds catchment took another three years to complete. Here the Committee looked at issues of water quality as well as quantity.

For many years the level of nitrate in groundwater has been growing in this catchment (as in other parts of the Ashburton district).

Many were concerned about a lack of water in the Hinds itself and in the drains and streams between State Highway 1 and the coast.

The Committee held a number of meetings in the Hinds and Mayfield halls. I well remember a briefing from Arowhenua on their links to the Hinds area. The Committee eventually reached a consensus, leading to recommendations to the two councils, public hearings and eventual decisions.

Tougher limits on the loss of nitrate in the catchment have been the most notable result, together with the trial of underground aquifer recharge.

Protecting biodiversity, braided rivers and Ashburton lakes

Biodiversity planting, attention to the condition of the big braided rivers, and the condition of the Ashburton Lakes have also been on the Committee’s radar. It faced many challenges and plenty still lie ahead.

Operating by consensus, the Committee has allowed disparate interests to talk things through without rancour. Essentially we have balanced scientific facts, differing community views and the impact of changing farm practices – whilst having no more power than that of making recommendations.

Our ideas have then been tested through independent hearings and survived as the basis of future action.

It will take years for the quality of underground water to improve, but I’ve no doubt the Committee will keep at its tasks. I wish it well.

Find out more