Benmore irrigation scheme plans expansion, opponents warn of effect on wildlife
If an application to extend irrigation between Lake Ruataniwha and Little Ben, towards Omarama, is approved it will be "another nail in the coffin" of several species and plants, Forest and Bird says.
Species such as weta and banded dotterel would suffer as well as over 100 invertebrates and plants, the organisation said.
Benmore Irrigation Company (BIC) has applied to the Canterbury Regional Council (ECan) to increase its scheme's irrigable area from 4000ha to 7658ha and discharge nutrients to water.
The application was notified on February 3 and submissions closed on March 3. A hearing began in Omarama on Monday.
David Caldwell chaired the hearing with other panel members, Sharon McGarry and Hoani Langsbury. The hearing is expected to include a site visit on Wednesday and conclude next week.
ECan consent planner Simon Woodlock previously reported on the application identifying effects on water quality and ecosystems; large areas of biodiversity being removed with no mitigation proposed; and significant effects on an area of important landscape value inconsistent with current relevant planning provisions.
He advised the consent not be granted.
Woodlock noted 25 submissions opposed to the proposal, two in support and two neither supporting nor opposing it.
DOC southern service centre plant ecology advisor Nicholas Head in his written submission says the Mackenzie Basin stands out nationally as one of the few remaining places to retain ecosystems that have been largely lost and fragmented elsewhere in the country.
"It mostly comprises naturally rare, glacial-derived ecosystems that are not replicated to any similar extent elsewhere in New Zealand, or the rest of the world. These ecosystems ... provide habitats for a disproportionately high number of threatened species.
"The impacts of irrigation on dryland ecosystems results in the almost complete loss of ecological values as the indigenous species and their habitats are lost to irrigation and associated cultivation, over-sowing and top dressing."
Head says BIC's proposed mitigation, such as removing wilding pines, was "not like for like, nor is the mitigation in perpetuity, giving no guarantees of lasting benefits."
"This will result in the permanent loss of irreplaceable, naturally rare ecosystems," he said in his written submission.
At the hearing, Duncan Cotterill lawyer Ewan Chapman presented BIC's legal submissions before shareholders, company representatives, and various experts gave evidence in support of BIC.
Chapman said BIC's current consent is for 35 years to February 2034. Any area under the overall command of the scheme can be irrigated by virtue of this consent, he said.
There would be no change to volume of water taken under the consent, he said.
No sites within the proposed irrigation area are identified as being within areas of significant indigenous vegetation and habitat of significant indigenous fauna identified on the planning maps and listed under the Waitaki District Plan, he said.
It also does not overlap with areas identified on the planning maps as outstanding natural landscapes, Chapman said.
BIC's responsibility to date has been to supply water to the farm gate. This would change to a focus on nutrient management.
"Like other irrigators in the Upper Waitaki, BIC will be brought in to line to paying for lake water quality testing and the consequences of those tests," Chapman said.
"Farmers will need to watch their soil moisture metering like a hawk because those parameters will set in place when irrigators can be turned on."
He said the application sets a process for weed and pest control and identifies gains in water quality in the sensitive water catchments.
"The conditions proposed by the applicant will take the Benmore consent from a rather uncontrolled irrigation regime to one with significant management and water quality controls."
The hearing, being held at the conference room at the Country Time Hotel in Omarama, continues.