Grey Valley irrigation water ‘steady’

Nicole Mathewson Reporter from The Press

From local democracy reporter Brendon McMahon:

Water levels for irrigation in the drought-hit upper Grey Valley have held steady but are still declining, the West Coast Regional Council says.

At this stage no irrigation consent holders in the district - which has a dozen or so farming operations with spray pivot irrigators - have been found to be operating outside their consent conditions, acting consents and compliance manager Rachel Clark said.

"It has held pretty steady - certainly it has been slowly declining but it has been at a great rate of knots.

"We haven't seen drastic drops that would cause us concern."

The council announced three weeks ago it was closely watching river levels in the Grey River catchment when at that stage there had been no substantial rain since early in December.

By January 10, with the extended fine weather, the council was looking to protect waterway health while enabling water consent holders to keep utilising their consents "as much as practicable".

And the picture has not really improved apart from some spasmodic local showers and a downpour in the lower Grey Valley-Greymouth area mid-morning today.

In the past seven days council rain data shows minimal rain across the valley catchment: Atarau had 23mm (15mm in the 24 hours to 10am today), Waipuna 17.5mm (6.5mm), Ngahere: 19mm (12mm), Arnold River at Moana: 22.5mm (10.5mm) and Ahaura River at the gorge: 6.5mm (3.5mm).

Clark said the council have been monitoring irrigation bores in spot checks plus monitoring water takes over a certain litre per second.

The council also has water monitoring stations on the Grey River catchment which provides automatic data to give a comparative picture.

The consent and conditions set what individual farmers were allowed to take although older existing consents were more liberal.

"Some do have a specific cut off level ... 35 years are the maximum. It does vary."

The water take cut-off in a consent was based on data from nearby or downstream monitoring sites.

Clark said it could only be hoped that the water table would be replenished with "gentle, regular" rain in the near future, in contrast to the current conditions being experienced in the North Island.

The regional council also needed to ensure water takes meet Resource Management Act amendment regulations which came into effect last September for water takes over 20 litres/second or more, she said.

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