'They're sitting on their hands:' Slow progress to Ashburton River flow target


The Ashburton river is flowing heavily after heavy rain, but a pledge to increase its flow permanently is making slow progress.

It has raged furiously for the last month, fuelled by recurring bouts of heavy rain, but it's a rare state of being for the Ashburton River.

Over summer, its usual flow is well below that of its natural state – increasing it has become a high priority for local authorities.

But years after committing to do so, little progress had been made, said Mary Ralston of Forest & Bird Ashburton.

The Ashburton River is flowing out to sea, rather than just trickling, after heavy rain.

The Ashburton River is flowing out to sea, rather than just trickling, after heavy rain.

"It's just not being pursued," she said.

"They're sitting on their hands... Because it's likely to impact on farmers' ability to irrigate, they just don't want to do it."

The river's mean annual low flow (MALF) has been between 2 and 3.5 cumecs for many years.

In its Land and Water Regional Plan, Environment Canterbury (ECan) said the river's MALF must increase to 6 cumecs by 2023.

The Ashburton zone committee's implementation plan goes further: It requires the target be met "as soon as possible".

A major contributor to the river's lower flow is abstraction: it is among the most heavily allocated rivers in New Zealand.

About 60 per cent of its mean flow is abstracted before the river reaches State Highway 1, according to an analysis by retired hydrologist John Waugh.

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When the 6 cumecs target was set, the river's abstraction allocation was 191 per cent – meaning the water being taken was nearly double of what had been set as the maximum limit.

There are 96 groundwater consents hydraulically connected to the river, and 52 surface water consents. While the surface water consents have flow restrictions, almost all of the groundwater takes do not.

It means nearly 100 water users can take water connected to the river until it is dry.

To meet the flow target, those consents would likely need to be reviewed, so limits could be put on them.

But nearly five years since the target was set, the review has not happened, despite general acknowledgment it was needed.

In 2012, the zone committee wrote to ECan raising concerns about the possibility of a review before other methods had been attempted.

"When and how such a process might take place is currently unclear," the letter said. "This appears to be creating a stressful situation among the abstractors."

It suggested pushing a review until 2017. ECan's response agreed with that timeframe.

No review is planned, which Ralston said showed an unwillingness to take necessary steps.

"If they'd started the process in 2011 when they were planning to, if they'd given farmers five years notice, they could have put other things in place, like storage dams or reviewed their methods," she said. 

"The process of reviewing consents could be well and truly underway. Until we get a review of these consents, with the minimum flow of the river of 6 cumecs as a condition, we're not going to get a reliable increase in the river flows."

Zone committee chairman William Thomas said other steps were being taken to meet the flow target.

"Ashburton District Council are on track to achieve their reduced stock water take as per Land and Water Regional Plan requirements," he said.

"A large water abstractor, Greenstreet Irrigation, has been granted consent to swap their water take from surface water to deep groundwater."

Other actions could be taken to increase flows, he said: more water users could apply to swap their takes to deep groundwater.

A group of abstractors had formed a group to work together to manage the river's flows, he said.

Regional councils can recall or review large numbers of consents if it is believed they are having an adverse environmental effect.

It is rarely done.



 - Stuff

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