NRC study evaluates future irrigation schemes

Lake Manuwai was formed in the 1980s for the Kerikeri Irrigation Scheme.

A comprehensive study scoping whether and where more irrigation schemes could sprout in Northland - and how much value they might add - should soon be ready for public scrutiny.

Northland Regional Council (NRC) commissioned the high-level Strategic Irrigation Infrastructure Study in 2014, spurred by three consecutive summer droughts and Government incentives for drought mitigation.

But the scope of the study goes much further than agriculture and horticulture benefits, with freshwater management and resource issues impacting on iwi, tourism, leisure and lifestyle included.

A report by consulting empire Opus last year identified broad issues and where dams might be located, recommending servicing clusters at Kaikohe, Waimate North, Kerikeri, Ruawai and Dargaville, NRC economist Darryl Jones said.

"We then asked can we scope up some options, including cropping needs, farming, other water use? We asked for more details.

"We now have a good idea of what's possible and have the information we need in hand on which to base a discussion.

"We're not necessarily drawing any lines on the map at this stage," Mr Jones said.

The 2015 Tai Tokerau Northland Growth Study noted the need to quantify as well as manage freshwater.

NRC's economic development agency Northland Inc also pushed for the Strategic Irrigation Infrastructure Study.

The NRC has spent $240,000 on the study and tapped into a matching amount from the Ministry of Primary Industries' Irrigation Acceleration Fund and Crown Irrigation Investigation.

In last year's shallower stage, the study concluded about 92,000ha could potentially be irrigated.

That irrigation could contribute up to $247 million annually to the region's GDP (a 4 per cent lift on current figures) and employ the equivalent of 3400 people full-time (a 6 per cent lift).

About 10,600ha are currently consented for irrigation although only about 8500ha are actually being irrigated, most of it for horticulture.

Northland only has two large scale irrigation schemes, both built in the 1980s; one at full capacity in Kerikeri, the other at Maungatapere.

How new schemes might be paid for, water allocation, charges and how private or public the schemes might be were all part of a conversation yet to be had.

The study will be available in a matter of weeks.

The matter will eventually be included the council's long-term plan process and open to submissions.

Forest and Bird's Northland conservation advocate Dean Baigent-Mercer said Northlanders should remember Hawke's Bay ratepayers' had $20m of their money poured down the drain before the controversial Ruataniwha Dam proposal was quashed.

"Northland Inc and the NRC needs to publicly explain what is in the pipeline, how much public money has been spent, how much debt these irrigation schemes would incur and which business interests are lobbying for these large irrigation dams in Northland," he said.